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BEGIN:VEVENT
SUMMARY:Studies of the 3D Structure of the Nucleon at JLab
DTSTART;VALUE=DATE-TIME:20150924T104500Z
DTEND;VALUE=DATE-TIME:20150924T111500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76722@agenda.infn.it
DESCRIPTION:Speakers: Harut Avakian (JLab)\nThe quark-gluon dynamics manif
ests itself in a set of non-perturbative functions describing all possibl
e spin-spin and spin-orbit correlations. The Transverse Momentum Dependen
t parton distributions (TMDs) and Generalized Parton Distributions (GPDs)
carry information not only on the longitudinal but also on the transvers
e momentum and position of partons\, providing rich and direct information
on the orbital motion of quarks. Single and Dihadron semi-inclusive and
hard exclusive production\, both in current and target fragmentation regi
ons\, provide a variety of spin and azimuthal angle dependent observables\
, sensitive to the dynamics of quark-gluon interactions. Studies of the 3D
PDFs are currently driving the upgrades of several existing facilities (J
Lab\, COMPASS and RHIC)\, and the design and construction of new facilitie
s worldwide (EIC\, FAIR\, and JPARC). \nIn this talk\, we present an overv
iew of the current status and some future measurements of the orbital str
ucture of nucleons and nuclei at Jefferson Lab.\n\nhttps://agenda.infn.it/
event/9011/contributions/76722/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76722/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hermes results on 3D imaging of the nucleon
DTSTART;VALUE=DATE-TIME:20150924T080000Z
DTEND;VALUE=DATE-TIME:20150924T083000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76721@agenda.infn.it
DESCRIPTION:Speakers: Luciano Libero Pappalardo (FE)\nIn the context of ra
pid theoretical developments in non-perturbative QCD\, a formalism of Tran
sverse Momentum Dependent parton distribution functions (TMDs) and of Gene
ralized Parton Distributions (GPDs) was introduced in the last two decades
\, providing a more comprehensive multi-dimensional description of the nuc
leon. TMDs and GPDs allow in fact for complementary descriptions of the nu
cleon in three dimensions (nucleon tomography)\, spanned by the quarks lon
gitudinal momenta and\, respectively\, by the their transverse momenta com
ponents and transverse spatial coordinates. They thus contribute\, with di
fferent approaches\, to the full phase-space description of the nucleon st
ructure. Furthermore\, they provide complementary insights into the yet un
measured quark orbital angular momentum. Experimentally\, TMDs and GPDs ca
n be accessed through the analysis of specific azimuthal asymmetries measu
red\, respectively\, in semi-inclusive deep-inelastic scattering and hard
exclusive processes\, such as hard leptoproduction of real photons or meso
ns. The HERMES experiment has collected wealth of data on scattering of a
longitudinally polarized lepton (electron or positron) beam from HERA off
unpolarized\, longitudinally and transversely polarized internal gas targe
ts. Collected data allowed to measure a variety of asymmetries with respec
t to beam charge\, beam helicity and target polarization. A selection of H
ERMES results on observables sensitive to TMDs and GPDs will be presented.
\n\nhttps://agenda.infn.it/event/9011/contributions/76721/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76721/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Solving the inhomogeneous Bethe-Salpeter Equation in Minkowski
space
DTSTART;VALUE=DATE-TIME:20150922T123000Z
DTEND;VALUE=DATE-TIME:20150922T130000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76720@agenda.infn.it
DESCRIPTION:Speakers: Michele Viviani (PI)\nThe inhomogeneous Bethe-Salpet
er Equation for an interacting system\, composed by two massive scalars ex
changing a massive scalar\, is numerically investigated in ladder approxim
ation\, directly in Minkowski space\, by using an approach based on the Na
kanishi integral representation. In this contribution\, the results obtain
ed for the scattering lengths and phase-shifts will be presented and compa
red with the analogous quantities recently obtained within a totally diffe
rent framework. Moreover\, a highly non trivial issue related to the abrup
t change in the width of the support of the Nakanishi weight function\, wh
en the zero-energy limit is approached\, will be discussed.\n\nhttps://age
nda.infn.it/event/9011/contributions/76720/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76720/
END:VEVENT
BEGIN:VEVENT
SUMMARY:POSTER SESSION
DTSTART;VALUE=DATE-TIME:20150922T155000Z
DTEND;VALUE=DATE-TIME:20150922T171000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76718@agenda.infn.it
DESCRIPTION:See on Monday 21 for Abstracts\n\nhttps://agenda.infn.it/event
/9011/contributions/76718/
LOCATION:LNF Hall Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76718/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Radon transform and light-cone distributions
DTSTART;VALUE=DATE-TIME:20150924T133000Z
DTEND;VALUE=DATE-TIME:20150924T140000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76717@agenda.infn.it
DESCRIPTION:Speakers: Oleg Teryaev (JINR)\nThe Radon transform application
s for relations between various light-cone distributions is considered. Th
e contributions of different channels to the inverse Radon transform for D
ouble Distributions are extracted. The relations between fracture and diha
dron fragmentation functions are analyzed. The transverse momentum depende
ncies for exclusive and semi-inclusive processes are \ncompared.\n\nhttps
://agenda.infn.it/event/9011/contributions/76717/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76717/
END:VEVENT
BEGIN:VEVENT
SUMMARY:TMD phenomenology
DTSTART;VALUE=DATE-TIME:20150921T070000Z
DTEND;VALUE=DATE-TIME:20150921T073000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76716@agenda.infn.it
DESCRIPTION:Speakers: Mauro Anselmino (TO)\nThe Transverse Momentum Depend
ent Partonic Distributions (TMD-PDFs) and Fragmentation Functions (TMD-FFs
) should reveal new properties of the 3-dimensional structure of nucleons
and of the quark hadronization process. Many experimental data are now ava
ilable and much progress has been made in their phenomenological interpret
ation. A short summary of the situation is presented.\n\nhttps://agenda.in
fn.it/event/9011/contributions/76716/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76716/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Basis Light Front Quantization - Recent Results and Future Prospec
ts
DTSTART;VALUE=DATE-TIME:20150925T094500Z
DTEND;VALUE=DATE-TIME:20150925T101500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76715@agenda.infn.it
DESCRIPTION:Speakers: James Vary (Iowa State University)\nLight-front Hami
ltonian field theory has advanced to the stage of becoming a viable non-pe
rturbative method for solving forefront problems in strong interaction phy
sics. Physics drivers include hadron mass spectroscopy\, generalized parto
n distribution functions\, \nspin structures of the hadrons\, inelastic st
rength functions\, hadronization\, particle production by strong external
time-dependent fields in relativistic heavy ion collisions\, and many more
.\nI will review selected recent results with Basis Light Front Quantizati
on (BLFQ) that include Fermion-Antifermion bound states in QED and in QCD.
I will then present a selection of near-term projects/plans and their ch
allenges. Computational resources on leadership class supercomputers play
an essential role in these projects/plans.\n\nhttps://agenda.infn.it/even
t/9011/contributions/76715/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76715/
END:VEVENT
BEGIN:VEVENT
SUMMARY:On Shell Optical Potential at very High Energies
DTSTART;VALUE=DATE-TIME:20150922T143000Z
DTEND;VALUE=DATE-TIME:20150922T145000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76714@agenda.infn.it
DESCRIPTION:Speakers: Enrique Ruiz Arriola (Universidad de Granada)\nWe an
alyze the usefulness of the optical potential as suggested \nby the double
spectral Mandelstam representation at very high energies. Its particular
meaning regarding the analysis of Nucleon-Nucleon scattering data up to th
e maximum available measured energies \nand implications in heavy-ions col
lisions is also discussed.\n\nhttps://agenda.infn.it/event/9011/contributi
ons/76714/
LOCATION:LNF\, High Energy Buiding no36 Aula Seminari
URL:https://agenda.infn.it/event/9011/contributions/76714/
END:VEVENT
BEGIN:VEVENT
SUMMARY:New Results for Hadron Physics from Light-Front Holography and Sup
erconformal Algebra
DTSTART;VALUE=DATE-TIME:20150925T101500Z
DTEND;VALUE=DATE-TIME:20150925T110000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76713@agenda.infn.it
DESCRIPTION:Speakers: Stanley Brodsky (SLAC National Accelerator Laborator
y\, Stanford University)\nLight-front holography provides a precise relat
ion between the bound-state amplitudes in the fifth dimension of AdS space
and the boost-invariant light-front wavefunctions describing the internal
structure of hadrons in physical space-time. The resulting valence Fock
-state wavefunctions of the light-front QCD Hamiltonian satisfy a relativi
stic equation of motion\, analogous to the nonrelativistic radial Schr\\"o
dinger equation\, with an effective confining potential. If one requires t
hat the effective action which underlies the QCD Lagrangian to remain co
nformally invariant and extends the formalism of de Alfaro\, Fubini and Fu
rlan to light front Hamiltonian theory\, the potential has a unique form o
f a harmonic oscillator potential\, and a mass gap arises. The result is
a nonperturbative relativistic light-front wave equation which incorporat
es color confinement and other essential spectroscopic and dynamical featu
res of hadron physics\, including a massless pion for zero quark mass and
linear Regge trajectories with the same slope in the radial quantum numbe
r n and orbital angular momentum L. One can also construct an effective QC
D light-front Hamiltonian for both mesons and baryons based on superconfor
mal algebra. The superconformal construction is shown to be equivalent to
a semiclassical approximation to light-front QCD and its embedding in AdS
space. The specific breaking of conformal invariance determines a unique e
ffective confinement potential. The generalized supercharges connect the b
aryon and meson spectra to each other in a remarkable manner. We also sho
w how the mass scale underlying confinement and hadron masses determines
the scale controlling the evolution of the perturbative QCD coupling. The
relation between scales is obtained by matching the nonperturbative dynam
ics\, as described by an effective conformal theory mapped to the light-fr
ont and its embedding in AdS space\, to the perturbative QCD regime. The
result is an effective coupling defined at all momenta.\n\nhttps://agenda
.infn.it/event/9011/contributions/76713/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76713/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Light-Front Quark Model Analysis of Meson-Photon Transition Form F
actor
DTSTART;VALUE=DATE-TIME:20150922T151000Z
DTEND;VALUE=DATE-TIME:20150922T153000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76712@agenda.infn.it
DESCRIPTION:Speakers: Ho-Meoyng Choi (Kyungpook National University)\nHadr
onic distribution amplitudes (DAs) provide essential\ninformation on the
QCD interaction of quarks\, antiquarks and gluons inside the hadrons and p
lay an essential role in applying QCD to hard exclusive processes such as
the pion-photon transition form factor (TTF). \nAs the discrepancy of $Q^2
F_{\\pi\\gamma}(Q^2)$ data between \nthe BaBar and Belle measurements has
not been \nresolved yet\, more studies on the meson-photon TTF are called
for. In particular\, \nthe pion-photon TTF still motivates more theoretica
l studies using various forms of pion DAs.\nThe general agreement on the a
nalysis of the pion DA is that the broader the\npion DA the steeper the sl
ope of $Q^2F_{\\pi\\gamma}(Q^2)$ as $Q^2$ is getting larger.\nFor instance
\, the flat pion DA $\\phi(x)=1$\nshows the agreement with the BaBar data
which kept rising over the Belle data\nas $Q^2$ gets larger. However\, the
flat pion DA $\\phi(x)=1$ is severely different from\nthe twist-2 asympto
tic DA $\\phi(x)=6x(1-x)$ which has been frequently discussed\nbased on th
e collinear factorization and QCD scaling.\nContrary to the pion-photon TF
F\,} the subsequent BaBar \ndata for the $(\\eta\,\\eta')\\to\\gamma^*\\ga
mma$ TFFs \nhave shown the consistency predicted by the perturbative QCD\,
where the use of flat DA for $\\eta$ and $\\eta'$ distributions \nappears
strongly disfavored by the datasets of $\\eta(\\eta')-\\gamma$ TFFs.\nThu
s\, the careful analysis of $(\\eta\,\\eta')\\to\\gamma^*\\gamma$ transit
ions is especially\nimportant under the circumstance of a prolonged disput
e over the pion-photon TFF results.\n\n\nIn this talk\, we investigate the
$P\\to\\gamma^*\\gamma (P=\\pi^0\,\\eta\,\\eta')$ transitions using \nthe
light-front quark model (LFQM)\nbased on the QCD motivated effective LF H
amiltonian.\nWe shall also show both timelike and spacelike TFF using the
analytic \ncontinuation method of changing $Q^2\\to -Q^2$ in the form fact
or.\nThe $\\eta-\\eta'$ mixing scheme is analyzed to obtain the optimum va
lues of the $\\eta(\\eta')-\\gamma$ TFFs and compared with the current ava
ilable experimental data.\n\nhttps://agenda.infn.it/event/9011/contributio
ns/76712/
LOCATION:LNF\, High Energy Buiding no36 Aula Seminari
URL:https://agenda.infn.it/event/9011/contributions/76712/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hadron structure from lattice QCD
DTSTART;VALUE=DATE-TIME:20150925T070000Z
DTEND;VALUE=DATE-TIME:20150925T073000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76711@agenda.infn.it
DESCRIPTION:Speakers: Gunnar Bali Bali (University of Regensburg)\nI revie
w recent hadron structure results of the Regensburg\ngroup.\n\nhttps://age
nda.infn.it/event/9011/contributions/76711/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76711/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sketching the pion's valence-quark Generalised Parton Distribution
DTSTART;VALUE=DATE-TIME:20150924T094500Z
DTEND;VALUE=DATE-TIME:20150924T101500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76710@agenda.infn.it
DESCRIPTION:Speakers: Hervé Moutarde (Irfu\, CEA-Saclay)\nIn order to lea
rn effectively from measurements of Generalised Parton Distributions (GPDs
)\, it is desirable to compute them using a framework that can potentially
connect empirical information with basic features of the Standard Model.
We sketch an approach to such computations\, based upon a rainbow-ladder
(RL) truncation of QCD's Dyson-Schwinger equations and exemplified via the
pion's valence dressed-quark GPD. Our analysis focuses primarily on vani
shing skewness\, although we also capitalise on the symmetry-preserving na
ture of the RL truncation by connecting the considered pion GPD with the p
ion's valence-quark parton Distribution Amplitude. We explain that the im
pulse-approximation used hitherto to define the pion's valence dressed-qua
rk GPD is generally invalid owing to omission of contributions from the gl
uons which bind dressed-quarks into the pion. A simple correction enables
us to identify a practicable improvement to the approximation for the pio
n GPD at vanishing skewness\, expressed as the Radon transform of a single
amplitude. Therewith we obtain results for the associated impact-paramete
r dependent distribution\, which provides a qualitatively sound picture of
the pion's dressed-quark structure at an hadronic scale. We evolve the d
istributions to the scale 2\\\,GeV\, so as to facilitate comparisons in fu
ture with results from experiment or other nonperturbative methods.\n\nhtt
ps://agenda.infn.it/event/9011/contributions/76710/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76710/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Electromagnetic properties of the nucleon in the covariant Faddeev
approach
DTSTART;VALUE=DATE-TIME:20150923T073000Z
DTEND;VALUE=DATE-TIME:20150923T080000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76708@agenda.infn.it
DESCRIPTION:Speakers: Gernot Eichmann (University of Giessen)\nThe covaria
nt three-body Faddeev approach and its application to nucleon and delta pr
operties are briefly reviewed. I will discuss results for mass spectra as
well as nucleon and delta elastic and transition form factors\, together w
ith the role of electromagnetic gauge invariance and vector-meson dominanc
e. I will also talk about some recent work on Compton scattering\, pion-cl
oud effects and the road towards timelike form factors.\n\nhttps://agenda.
infn.it/event/9011/contributions/76708/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76708/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Valon model for double parton distributions
DTSTART;VALUE=DATE-TIME:20150921T104500Z
DTEND;VALUE=DATE-TIME:20150921T111500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76707@agenda.infn.it
DESCRIPTION:Speakers: Wojciech Broniowski (Jan Kochanowski U. and Institut
e on Nuclear Physics PAN\, Poland)\nWe explore ansatze for parton distribu
tions of the proton following the idea of the valon model\, where the Fock
components have the form f1(x_1)f1(x_2)...fn(x_n)delta(1-x_1-x_2-...-x_n)
. Upon integration\, double and single parton distributions are generated
from the n-particle distributions. We show that the construction leads to
preservation of the Gaunt-Stirling sum rules\, thus providing distribution
s with the required features which can be used in phenomenological studies
.\n\nhttps://agenda.infn.it/event/9011/contributions/76707/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76707/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Proton structure in high-energy high-multiplicity p-p collisions
DTSTART;VALUE=DATE-TIME:20150921T133000Z
DTEND;VALUE=DATE-TIME:20150921T140000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76706@agenda.infn.it
DESCRIPTION:Speakers: Stanislaw Glazek (University of Warsaw)\nRidge-like
correlations in high-energy proton-proton collisions\nreported by the CMS
collaboration suggest a collective flow that \nresembles the one in heavy-
ion collisions. If the hydrodynamic \ndescription is valid then the effect
results from the initial \nanisotropy of the colliding matter\, which dep
ends on the distribution \nof matter in protons. Following recent theoreti
cal developments\, we \npropose several phenomenological models of the pro
ton structure and \nestimate the associated anisotropy coefficients in p-p
collisions\nusing the Monte Carlo Glauber model[1]. Our estimates suggest
that \nthe initial anisotropy in some models appears capable of accountin
g \nfor the p-p ridge effect\, with potentially discernible differences \n
in dependence on multiplicity.\n\n[1] P. Kubiczek\, S. D. Glazek\, arXiv:1
505.04155 [hep-ph].\n\nhttps://agenda.infn.it/event/9011/contributions/767
06/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76706/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Quark Orbital Angular Momentum
DTSTART;VALUE=DATE-TIME:20150921T083000Z
DTEND;VALUE=DATE-TIME:20150921T090000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76705@agenda.infn.it
DESCRIPTION:Speakers: Matthias Burkardt (New Mexico State University)\nDef
initions of orbital angular momentum based on Wigner distributions are use
d to discuss the connection between the Ji definition of the quark orbital
angular momentum and that of Jaffe and Manohar. The difference between th
ese two definitions can be interpreted as the change in the quark orbital
angular momentum as it leaves the target in a DIS experiment. The mechanis
m responsible for that change is similar to the mechanism that causes tran
sverse single-spin asymmetries in semi-inclusive deep inelastic scattering
. A sum rule for quark orbital angular momentum based on a twist 3 GPD is
also discussed.\n\nhttps://agenda.infn.it/event/9011/contributions/76705/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76705/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Deuteron electromagnetic form factors in AdS/QCD
DTSTART;VALUE=DATE-TIME:20150922T153000Z
DTEND;VALUE=DATE-TIME:20150922T155000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76704@agenda.infn.it
DESCRIPTION:Speakers: Valery Lyubovitskij (Tuebingen University\, Germany)
\nWe present a high-quality description of the deuteron electromagnetic \
nform factors in a soft-wall AdS/QCD approach [1]. We propose an effective
action describing the dynamics of the deuteron in the presence of an ext
ernal vector field. Based on this action the deuteron \nelectromagnetic fo
rm factors are calculated\, displaying the correct (1/Q2)**5 power scalin
g for large Q2 values. This finding is \nconsistent with quark counting ru
les and the earlier observation that \nthis result holds in confining gau
ge/gravity duals. The Q2 dependence \nof the deuteron form factors is def
ined by a single and universal scale parameter kappa\, which is fixed from
data.\n\n\n[1] T. Gutsche\, V. E. Lyubovitskij\, I. Schmidt and A. Vega\,
\n``Nuclear physics in soft-wall AdS/QCD: Deuteron electromagnetic form fa
ctors\,'' Phys. Rev. D 91\, 114001 (2015) \n[arXiv:1501.02738 [hep-ph]].\n
\nhttps://agenda.infn.it/event/9011/contributions/76704/
LOCATION:LNF\, High Energy Buiding no36 Aula Seminari
URL:https://agenda.infn.it/event/9011/contributions/76704/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Electronic Helicity Flipping via Podolsky in the Light Front
DTSTART;VALUE=DATE-TIME:20150921T161000Z
DTEND;VALUE=DATE-TIME:20150921T161000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76703@agenda.infn.it
DESCRIPTION:Speakers: Jorge Sales (Universidade Estadual de Santa Cruz\, D
CET-PPGMC)\nThe generalized elecrodynamics proposed by Podolsky is based o
n the Lagrangian density\n\\begin{equation*}\n{\\cal L}_{\\text{o}}=-\\fra
c{1}{4}F^{\\mu \\nu }F_{\\mu \\nu }+\\frac{a^{2}}{2}\\partial\n_{\\nu }F^{
\\mu \\nu }\\partial ^{\\lambda }F_{\\mu \\lambda }\,\n\\end{equation*}%\n
in which $a$ is a constant with dimension of length. This Lagrangian densi
ty generates a linear field theory\, with gauge symmetry of the type $U(1)
$\, that reduces to the Maxwell theory when we let $a=0$. Evidently this i
s a higher order theory since the equations of movement contain fourth ord
er derivatives of the vector potential. As in the Maxwell's theory\, Podol
sky's theory also pesents positive definite energy in the electrostatic ca
se that\, nonetheless\, is finite for a point charge. This last result cle
arly shows that the force between two point charges is no longer of Coulom
b type\, a point that deserves to be closely looked at. \n\nIn this work w
e focus on the Podolsky's electrodynamics on the light front. As a consequ
ence\, it is shown that the electron's helicity is flipped.\n\nhttps://age
nda.infn.it/event/9011/contributions/76703/
LOCATION:Laboratori Nazionali di Frascati Hall Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76703/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Extraction of TMDs from experimental data
DTSTART;VALUE=DATE-TIME:20150924T070000Z
DTEND;VALUE=DATE-TIME:20150924T073000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76702@agenda.infn.it
DESCRIPTION:Speakers: Alessandro Bacchetta (PV)\nI will review the current
status of the extraction of Transverse Momentum Distributions (TMDs) from
experimental data. We are gaining an ever increasing knowledge about TMDs
\, both unpolarized and polarized\, but we are still far from a precise de
termination of these quantities. Central issues are currently related to t
he implementation of TMD evolution in the extractions. To make further pro
gress\, new experimental data are also needed.\n\nhttps://agenda.infn.it/e
vent/9011/contributions/76702/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76702/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Internal stucture of the pion inspired by AdS/QCD correspondence
DTSTART;VALUE=DATE-TIME:20150921T153000Z
DTEND;VALUE=DATE-TIME:20150921T155000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76701@agenda.infn.it
DESCRIPTION:Speakers: Sabrina Cotogno (Vrije Universiteit Amsterdam and Ni
khef)\nThe Light-Front Wave Functions (LFWFs) represent a perfect starting
point for describing the partonic structure of hadrons.\nIn this work we
use the results for the LFWFs of the pion coming from the AdS/QCD correspo
ndence\, in the context of a soft-wall model. We study the parton distribu
tion function (PDF) and the electromagnetic form factor (FF) of the pion a
nd for the first time we implement the analysis of the unpolarized transve
rse momentum dependent parton distribution (TMD) $f_1(x\,\\mathbf{k}_\\bot
)$.\nThe correspondence has also been used to investigate the transition o
f the QCD coupling from high to low scales. In our analysis we obtain a va
lue for the physical mass scale parameter $\\kappa$ which can also be used
to calculate the QCD effective coupling predicted by this approach.\n\nht
tps://agenda.infn.it/event/9011/contributions/76701/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76701/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Proton spin structure from large momentum effective theory
DTSTART;VALUE=DATE-TIME:20150924T123000Z
DTEND;VALUE=DATE-TIME:20150924T130000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76700@agenda.infn.it
DESCRIPTION:Speakers: Jianhui Zhang (Regensburg University)\nUnderstanding
the spin structure of the proton has been an important goal in hadron phy
sics. One of the well-known spin sum rule\, the Jaffe-Manohar sum rule\, i
s motivated from a free-field expression of QCD angular momentum and has a
natural partonic interpretation. However\, this natural partonic sum rule
exhibits a gauge dependence in its individual contributions (apart from t
he quark spin). I will explain how these individual contributions arise fr
om gauge-invariant\, but frame-dependent operator matrix elements in the s
pirit of the large momentum effective theory\, which also provides a pract
ical possibility to compute the partonic orbital angular momentum in the p
roton. I will also explain how to compute parton distribution functions fo
llowing the same spirit.\n\nhttps://agenda.infn.it/event/9011/contribution
s/76700/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76700/
END:VEVENT
BEGIN:VEVENT
SUMMARY:OAM measurements from DVCS at JLab
DTSTART;VALUE=DATE-TIME:20150924T143000Z
DTEND;VALUE=DATE-TIME:20150924T145000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76698@agenda.infn.it
DESCRIPTION:Speakers: Silvia Pisano (LNF)\nDeeply-Virtual Compton scatteri
ng provides the cleanest access to the 3D imaging of the nucleon structure
encoded in the Generalized Parton Distributions\, that correlate the frac
tion of the total nucleon momentum carried by a constituent to its positio
n in the transverse plane. Besides the information on the spatial imaging
of the nucleon\, GPDs provide an access\, through the Ji relation\, to the
quark contribution to the nucleon total angular momentum. An accurate est
imate of such a contribution will lead to a better understanding of the or
igin of the proton spin. Jefferson Lab has been an ideal environment for t
he study of exclusive processes\, thanks to the combination of the high-in
tensity and high-polarization electron beam provided by the CEBAF\, with t
he complementary equipments of the three experimental halls. This has allo
wed high-precision measurements of the DVCS observables in a wide kinemati
c region\, with focus on those observables that provide access to the GPDs
entering the Ji relation. These studies will be further widened by the pr
ojected data from the 12-GeV era\, which will improve the existing measure
ments both in terms of precision and phase-space coverage. The important r
esults on the proton DVCS obtained during the 6-GeV era will be discussed\
, together with the upcoming experiments approved for the 12-GeV upgrade\,
that foresees measurements with both proton and neutron targets and that\
, when combined\, will lead to the extraction of the GPDs for separate qua
rk flavors.\n\nhttps://agenda.infn.it/event/9011/contributions/76698/
LOCATION:LNF\, High Energy Building no 36 Aula Seminari
URL:https://agenda.infn.it/event/9011/contributions/76698/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Overview of COMPASS Experimental Program for GPDs and TMDs
DTSTART;VALUE=DATE-TIME:20150925T091500Z
DTEND;VALUE=DATE-TIME:20150925T094500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76697@agenda.infn.it
DESCRIPTION:Speakers: Franco Bradamante (TS)\nCOMPASS is a fixed target ex
periment at the CERN SPS taking data since 2002. A major part of the COMPA
SS program at CERN is dedicated to the investigation of the 3 dimensional
structure of the nucleon which can be reached measuring the spin and trans
verse momentum dependent distributions (TMDs) and generalized parton distr
ibutions (GPDs).\nTMDs have been investigated at COMPASS in semi-inclusive
processes (SIDIS) using scattering of 160 GeV longitudinally polarized mu
ons on transversely polarized targets. This includes the measurements of t
he Collins and Sivers asymmetries observed in production of single pions o
r kaons on both proton and deuteron targets\, as well as all the other six
asymmetries in the case of non identified hadrons. The large statistics c
umulated with the proton target allows multidimensional analysis to invest
igate for example Q2 evolution. The similarity of Collins effects induced
by single and di-hadron production will be discussed. New results on the
Sivers gluon asymmetry on protons and deuterons will also be given. Finall
y the first-ever polarized Drell-Yan experiment using scattering of 190 Ge
V pions on a transversely polarized target which is presently performed a
t COMPASS in 2015 will be presented. This will allow the measurement of th
e TMDs functions in both SIDIS and DY and the study of their universality
in the same kinematical domain with a same apparatus.\nGPDs are experiment
ally accessible via lepton-induced exclusive reactions\, in particular the
Deeply Virtual Compton Scattering (DVCS) and Deeply Virtual Meson Product
ion (DVMP). A complete measurement of the eight asymmetries for exclusive
rho0 and omega productions have already been performed by COMPASS at the s
ame time than the SIDIS studies using the transversely polarized target b
ut without any recoil particle detection. Results which involve GPD H and
E and also chiral-odd or transverse GPDs will be presented. In 2016 and
2017 DVCS and DVMP will be investigated using the muon beam of 160 GeV and
a 2.5 m long liquid hydrogen target. In order to optimize the selection o
f exclusive reactions at those energies\, the target will be surrounded by
a newly built barrel-shaped time-of-flight system to detect the recoiling
particles. The option to change simultaneously the charge and polarizatio
n of the muon beam in the DVCS process will allow to access both real and
imaginary parts of the Compton form factor related to the dominant GPD H.
Moreover the xBj-dependence of the nucleon transverse size will be investi
gated via the pure DVCS or meson cross sections. In parallel to the DVCS a
nd DVMP\, SIDIS measurements will provide clean cross section data for the
extraction of multiplicities and possibly of the Boer Mulders function fr
om the azimuthal modulations.\n\nhttps://agenda.infn.it/event/9011/contrib
utions/76697/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76697/
END:VEVENT
BEGIN:VEVENT
SUMMARY:An asymptotic solution of large-N QCD\, for the glueball and meson
spectrum and the collinear S-matrix
DTSTART;VALUE=DATE-TIME:20150922T083000Z
DTEND;VALUE=DATE-TIME:20150922T090000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76696@agenda.infn.it
DESCRIPTION:Speakers: Marco Bochicchio (ROMA1)\nWe work out the constraint
s that the renormalization group imposes\non two- and three-point\, and ce
rtain multi-point correlators\nand S-matrix amplitudes\, in large-N QCD an
d\, more generally\,\nin any large-N confining asymptotically free gauge t
heory.\nWe construct a twistorial string theory that implies the QCD large
-N\nglueball and meson spectrum and collinear S-matrix\,\nthat satisfies t
he aforementioned constraints as opposed to all the previously\nknown stri
ng-inspired models\, including those based on gauge/gravity duality.\nIn p
articular we predict the spectrum of odd-spin glueballs\,\nyet to be obser
ved\, but in the experimental reach of GlueX or of\nother experiments.\n\n
https://agenda.infn.it/event/9011/contributions/76696/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76696/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Search for Light Dark Matter at accelerators
DTSTART;VALUE=DATE-TIME:20150925T080000Z
DTEND;VALUE=DATE-TIME:20150925T083000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76695@agenda.infn.it
DESCRIPTION:Speakers: Marco Battaglieri (Istituto Nazionale di Fisica Nucl
eare)\nIn the last few years interest for Light Dark Matter (LDM) in the M
eV - GeV range has been increasingly growing. Direct detection of non-rela
tivistic dark matter particles from the Galactic halo mainly focused to hi
gher masses(> 10 GeV) being insensitive to few-GeV or lighter DM\, whose n
uclear scattering transfers invisibly small kinetic energy to a recoiling
nucleus. On the other hand availability of high intensity\, high precision
and moderate energy electron beams allow for testing different LDM scenar
ios leaving to accelerator-based experiments the opportunity to explore an
equally promising but uncovered territory. In this talk I will review the
latest experimental results for LDM searches as well as the new experimen
ts proposed in different laboratories.\n\nhttps://agenda.infn.it/event/901
1/contributions/76695/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76695/
END:VEVENT
BEGIN:VEVENT
SUMMARY:POSTER SESSION
DTSTART;VALUE=DATE-TIME:20150924T161000Z
DTEND;VALUE=DATE-TIME:20150924T170000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76694@agenda.infn.it
DESCRIPTION:See on Monday 21 for Abstracts\n\nhttps://agenda.infn.it/event
/9011/contributions/76694/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76694/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Scattering Solutions of the Bethe-Salpeter equation in Minkowski a
nd Euclidean spaces
DTSTART;VALUE=DATE-TIME:20150923T070000Z
DTEND;VALUE=DATE-TIME:20150923T073000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76693@agenda.infn.it
DESCRIPTION:Speakers: Jaume Carbonell (CNRS/IPN Orsay)\nThe solutions of t
he Bethe-Salpeter equation in Minkoswki space are mandatory for computing
\nsome physical quantities like elastic and transition form factors\, scat
tering of-shell amplitudes etc.\nThey are however plagued with the singula
rities of the free propagators\, of the interaction\nkernel and of the amp
litude itself making rather difficult its numerical computation.\nThis dif
ficulty was overcome in the 50's with the use of the "Wick rotation"\, \nw
hich transforms the Minkowski into an Euclidean metric \nand allowed to ob
tain some observables invariant in this transformation.\nThe Euclidean Qua
ntum Field Theory is nowadays a basic ingredient in all the lattice calcul
ations.\nWe will see that this procedure is not always legitimate - at lea
st in the original framework \nwhere its was formulated - without a detail
ed knowledge of the analytic structure of \nthe Bethe-Salpeter amplitude i
n the complex momentum plane.\n\nWe will present two methods to obtain the
Minkowski solutions for bound and scattering states.\nThe first one is ba
sed on the Nakanishi integral transform and the projection of the Bethe-Sa
lpeter equation into the Light Front.\nThe second method is based on a car
eful analysis of the singularities and a direct solution of the original e
quation.\nIn particular we will show the possibility to extract the scatte
ring lenght from a purely euclidean solution.\nThis approach is directly a
pplicable in Euclidean Lattice calculations\nand provides a direct way to
obtain the scattering length without making use of the Luscher formula.\n\
nhttps://agenda.infn.it/event/9011/contributions/76693/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76693/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hidden Conformal Symmetry of Maxwell's Theory in $d\\neq 4$
DTSTART;VALUE=DATE-TIME:20150924T143000Z
DTEND;VALUE=DATE-TIME:20150924T145000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76692@agenda.infn.it
DESCRIPTION:Speakers: Kelly Chiu (SLAC)\nIn this work\, we define a modifi
ed non-local conformal transformation compatible with BRST formalism for $
U(1)$ gauge field\, which is a symmetry of the Maxwell's theory in any dim
ension. We prove the invariance by explicitly showing that the gauge invar
iant transverse two point function\, the classical action\, and equation o
f motion are unchanged under such transfomation.\n\nhttps://agenda.infn.it
/event/9011/contributions/76692/
LOCATION:LNF\, High Enegy Building n. 36 Aula A1
URL:https://agenda.infn.it/event/9011/contributions/76692/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jefferson Lab: Present and Future
DTSTART;VALUE=DATE-TIME:20150925T073000Z
DTEND;VALUE=DATE-TIME:20150925T080000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76691@agenda.infn.it
DESCRIPTION:Speakers: Patrizia Rossi (Jefferson Lab)\nThe Continuous Elect
ron Beam Accelerator Facility (CEBAF) and associated experimental equipmen
t at Jefferson Lab comprise a unique facility for nuclear physics research
whose upgrade is presently underway\, with completion expected in 2017.
\nThe upgraded facility will accelerate electron beams to 11 GeV for exper
iments in the existing Halls A\, B and C. In addition\, a 12 GeV beam can
be provided to a new experimental Hall D to generate a 9 GeV tagged photon
beam. \nThis upgrade will enable a new experimental program with substant
ial discovery potential to address important topics in hadronic\, nuclear\
, and electroweak physics. \nFurther in the future\, it is envisioned that
the Laboratory will evolve into an electron-ion colliding beam facility (
EIC).\nIn this talk the status of the 12 GeV upgrade and the associated ex
perimental program will be presented as well as a brief overview of the EI
C project.\n\nhttps://agenda.infn.it/event/9011/contributions/76691/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76691/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Registration
DTSTART;VALUE=DATE-TIME:20150921T060000Z
DTEND;VALUE=DATE-TIME:20150921T064500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76690@agenda.infn.it
DESCRIPTION:https://agenda.infn.it/event/9011/contributions/76690/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76690/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Exploring the Glue that Binds Us All: Science of the Electron Ion
Collider in the US
DTSTART;VALUE=DATE-TIME:20150921T073000Z
DTEND;VALUE=DATE-TIME:20150921T080000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76689@agenda.infn.it
DESCRIPTION:Speakers: Abhay Deshpande (Stony Brook University)\nDeep Inela
stic Scatting is arguably the best experimental technique employed by phys
icists to study the fundamental structure of nucleons and nuclei. Much of
what we know about the quark gluon\nstructure of the nucleons and nuclei c
omes form experiment performed in polarized and unpolarized fixed-target e
xperiments around the world\, and those performed at DESY using the HERA c
ollider. However many important questions related to the gluon’s role in
QCD still remain unanswered. Many of these relate to collective behavior
of partons (mostly gluons) in (polarized) nucleons and in nuclei at high e
nergy. Without understanding those\, we simply can not say we understand Q
CD\, the theory of strong interactions in the Standard Model\, completely.
The missing experimental data that will guide our understanding of QCD\na
nd address those questions\, will require high-energy polarized electron-n
ucleon\, and electron-nuclear collisions with a wide range in the size of
the nuclei. High-energy and polarization are critical for addressing this
in a future collider. The Electron Ion Collider (EIC) being considered in
the US is planned with precisely this in mind. Further\, the systematic st
udy of the nucleon and its spin properties\, including the position and mo
mentum correlations amongst the parsons inside the nucleons (resulting in
possible tomographic images of the nucleons) will require a sufficiently h
igh luminosity. I will summarize the gluon related open questions in QCD a
nd present the capabilities of the EIC in addressing them. I will also pre
sent the present status of the EIC project\, and invite you to support it
and get involved.\n\nhttps://agenda.infn.it/event/9011/contributions/76689
/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76689/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Quark and gluon orbital angular momentum: where are we?
DTSTART;VALUE=DATE-TIME:20150921T080000Z
DTEND;VALUE=DATE-TIME:20150921T083000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76688@agenda.infn.it
DESCRIPTION:Speakers: Cedric Lorce (IPNO and LPT Orsay\, Universite Paris-
Sud)\nThe orbital angular momentum of quarks and gluons contributes signif
icantly to the proton spin budget and attracted a lot of attention in the
recent years\, both theoretically and experimentally. We summarize the var
ious definitions of parton orbital angular momentum together with their re
lations with parton distributions functions. In particular\, we highlight
current theoretical puzzles and give some prospects.\n\nhttps://agenda.inf
n.it/event/9011/contributions/76688/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76688/
END:VEVENT
BEGIN:VEVENT
SUMMARY:On $0^{--}$ glueballs
DTSTART;VALUE=DATE-TIME:20150921T161000Z
DTEND;VALUE=DATE-TIME:20150921T163000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76687@agenda.infn.it
DESCRIPTION:Speakers: Loredana Bellantuono (BA)\nThe spectrum of the glueb
all with $J^{PC}=0^{--}$ is computed using different bottom-up holographic
models of QCD. The results indicate a lowest-lying state lighter than in
the determination by other methods\, with mass $m \\simeq 2.8$ GeV. The in
-medium properties of this gluonium are investigated\, and stability again
st thermal and density effects is compared to other hadronic systems. Prod
uction and decay modes are identified\, useful for searching the $J^{PC}=0
^{--}$ glueball.\n\nhttps://agenda.infn.it/event/9011/contributions/76687/
LOCATION:Laboratori Nazionali di Frascati Hall Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76687/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Integrated and unintegrated PDFs and GPDs from effective two-body
light-cone wave functions
DTSTART;VALUE=DATE-TIME:20150921T094500Z
DTEND;VALUE=DATE-TIME:20150921T101500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76686@agenda.infn.it
DESCRIPTION:Speakers: Dieter Mueller (Ruhr-University Bochum)\nWe introduc
e a classification scheme for parton distribution models and we model gen
eralized parton distributions (GPDs)\, their form factors\, and parton dis
tribution functions (PDFs)\, integrated and unintegrated ones\, in terms
of unintegrated double distributions that are obtained from the parton num
ber conserved overlap of effective light-cone wave functions. For a so-ca
lled "spherical" model we present general expressions for all twist-two re
lated non-perturbative quantities in terms of one effective light-cone wav
e function\, including chiral-odd GPDs. We also discuss the Regge improvem
ent of such quark models from the $s$-channel point of view and study the
relations between zero-skewness GPDs and unintegrated PDFs on a more gener
al ground.\n\nhttps://agenda.infn.it/event/9011/contributions/76686/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76686/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Covariant Spectator Theory and Hadron structure
DTSTART;VALUE=DATE-TIME:20150922T104500Z
DTEND;VALUE=DATE-TIME:20150922T111500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76685@agenda.infn.it
DESCRIPTION:Speakers: Teresa Pena (IST Lisboa)\nWe use the Covariant Spect
ator Theory (CST) \\cite{FG}\, which can be viewed as a reorganization of
the Bethe-Salpeter equation (BSE) that works in Minkowski space\, to devel
op a dynamical quark model that can describe the structure and the mass sp
ectrum of both\, heavy and light quark systems.\n We study mesonic structu
re and spectra. Treating mesons as effective qq states\, our focus is on t
he nonrelativistic bound-state problem in momentum space and on the electr
omagnetic pion form factor. The quark-quark interaction kernel is used to
calculate the quark self-energy in a consistent way\, resulting in a momen
tum dependent quark mass function. The kernel includes a confining term th
at in the nonrelativistic limit reduces to a linear potential. Chiral symm
etry is satisfied.\n\nhttps://agenda.infn.it/event/9011/contributions/7668
5/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76685/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Theory of Double Parton Scattering
DTSTART;VALUE=DATE-TIME:20150921T101500Z
DTEND;VALUE=DATE-TIME:20150921T104500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76684@agenda.infn.it
DESCRIPTION:Speakers: Jonathan Gaunt (DESY)\nDouble parton scattering (DPS
) is the process in which two distinct pairs of partons hard scatter in an
individual proton-proton collision. It can be an important background to
single scattering processes suppressed by small or multiple coupling const
ants (e.g. new physics signals)\, and can reveal novel information about t
he proton structure. I review recent developments in the endeavour to desc
ribe this process theoretically using a 'hard scattering factorisation' fr
amework.\n\nhttps://agenda.infn.it/event/9011/contributions/76684/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76684/
END:VEVENT
BEGIN:VEVENT
SUMMARY:The electron in three-dimensional momentum space
DTSTART;VALUE=DATE-TIME:20150922T145000Z
DTEND;VALUE=DATE-TIME:20150922T151000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76683@agenda.infn.it
DESCRIPTION:Speakers: Luca Mantovani (PV)\nWe study the electron at order
alpha as a system composed by an electron and a photon within the framewo
rk of light-front quantization. We derive the leading-twist transverse-mom
entum dependent distribution functions for both the electron and photon in
the dressed electron\, using different gauge prescriptions. In particular
\, we discuss the light-cone gauge and the Feynman gauge\, applying both t
he formalism of light-front wave function overlap representation and the
diagrammatic approach. Furthermore\, we present a detailed discussion of t
he role of the Wilson lines to obtain gauge-independent results.\n\nhttps:
//agenda.infn.it/event/9011/contributions/76683/
LOCATION:LNF\, High Energy Building n.36 AULA A1
URL:https://agenda.infn.it/event/9011/contributions/76683/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Understanding Transverse Momentum Dependent Functions from data.
DTSTART;VALUE=DATE-TIME:20150921T151000Z
DTEND;VALUE=DATE-TIME:20150921T153000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76682@agenda.infn.it
DESCRIPTION:Speakers: Jose Osvaldo Gonzalez Hernandez (TO)\nThe role of TM
Ds in understanding the 3D-structure of hadrons has drawn a lot of interes
t in both the theoretical and experimental communities. In order to extrac
t TMDs\, it is necessary to understand what information is contained in th
e different sets of data that are available. In this talk\, I will discuss
the advantages and limitations of some of the most recent experimental da
ta\, in the context of TMD-extraction.\n\nhttps://agenda.infn.it/event/901
1/contributions/76682/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76682/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gravitational form factor\, transverse spin sum rule and longitudi
nal momentum density in the transverse plane in a light front quark-diquar
k model of nucleons
DTSTART;VALUE=DATE-TIME:20150921T145000Z
DTEND;VALUE=DATE-TIME:20150921T151000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76681@agenda.infn.it
DESCRIPTION:Speakers: Dipankar Chakrabarti (Indian Institute of Technology
Kanpur\, India)\nIn lightcone framework\, longitudinal angular momentum o
perator is kinematical but the transverse angular momentum operator is dyn
amical and thus \nunderstanding the transverse spin and transverse angular
momentum of the proton is more complicated than longitudinal spin and ang
ular momentum and frame dependent.\nHere\, we evaluate the gravitational f
orm factors for a transversely polarized proton from the energy momentum t
ensor and evaluate the Pauli-Lubanski operator to verify a sum rule for th
e transverse spin in a light front scalar quark-diquark model with the lig
ht front wave functions constructed from a soft-wall AdS/QCD model.\nFurth
er\, the Fourier transform of the gravitational form factor $A(Q^2)$ in th
e impact parameter space gives the longitudinal momentum density in the tr
ansverse impact parameter space.\nThe longitudinal momentum densities in t
he transverse impact parameter space are discussed for both unpolarized
and transversely polarized nucleons in the quark-diquark model. For the u
npolarized nucleon\, the distribution is axially symmetric whereas for the
transversely polarized nucleon the distribution becomes distorted and our
analysis shows that the distortion is dipolar in nature.\n\nhttps://agen
da.infn.it/event/9011/contributions/76681/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76681/
END:VEVENT
BEGIN:VEVENT
SUMMARY:PION LIGHT-FRONT WAVE FUNCTION FROM LATTICE RESULTS
DTSTART;VALUE=DATE-TIME:20150921T161000Z
DTEND;VALUE=DATE-TIME:20150921T161000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76680@agenda.infn.it
DESCRIPTION:Speakers: Clayton Santos Mello (Instituto Tecnológico de Aero
náutica)\nIn this work\, we study the pion valence wave function by start
ing with an analytic parametrisations of the vertex function and \n runnin
g quark mass fitted to lattice-QCD results. We also investigate the pion e
lectromagnetic structure of the pion\, which is a \n pseudoscalar meson co
mposed of a quark-antiquark bound state\, i.e.\, $|u \\ \\bar{d}>$ with t
otal spin zero and negative parity.\nOur proposal is to obtain a wave func
tion from the Lattice-QCD results\, \nwhich describes the internal structu
re of the pion. In particular we calculate observables like \nthe electro
magnetic form factor and mean square radius.\nWe compute the wave function
by using a model with a running constituent quark mass. \nSpecifically\,
we performed the calculations in the Light-Front formalism with a Bethe-Sa
lpeter (BS) amplitude model with constituent quarks\,\nwhich forms the pio
n composite state. The calculations will be compared with other models in
the \nliterature\, which present different form for the pion light-front w
ave function. We take care of the Dirac matrix spinor structure of the BS
amplitude.\nIn a first approximation\, we disregarded the Dirac structure\
, and make\nthe first estimates for the wave function. Due to presence of
poles also in the quark mass function\, we approximated it by a constant
of $\\Sigma^2=0.300 \\ GeV^2$\, \nbut this was only as a first step in our
study of the wave function. For this purpose\, we analyzed the poles of t
he Bethe-Salpeter amplitude in the momentum\, which are integrated via Ca
uchy's theorem to eliminate te relative light-front time between the quark
s\, and in this way we derived the valence wave function.\n\nhttps://agend
a.infn.it/event/9011/contributions/76680/
LOCATION:Laboratori Nazionali di Frascati Hall Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76680/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Light Front Perturbation without Spurious Singularities
DTSTART;VALUE=DATE-TIME:20150922T153000Z
DTEND;VALUE=DATE-TIME:20150922T155000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76679@agenda.infn.it
DESCRIPTION:Speakers: Jerzy A. Przeszowski (Faculty of Physics\, Universit
y of Bialystok)\nA new form of the light front Feynman propagators is prop
osed. It \ncontains no energy denominators. Instead the dependence on the
\nlongitudinal subinterval x^2_L = 2 x^{+} x^{-} is explicit and\na new fo
rmalism for doing the perturbative calculations is invented.\nThese novel
propagators are implemented for the one-loop scattering matrix for a massi
ve scalar field. The consistency with results for the standard covariant F
eynman diagrams is obtained and no spurious singularities are encountered
at any step. Some remarks on the calculations with fermion and gauge field
s in QED and QCD are added.\n\nhttps://agenda.infn.it/event/9011/contribut
ions/76679/
LOCATION:LNF\, High Energy Building n.36 AULA A1
URL:https://agenda.infn.it/event/9011/contributions/76679/
END:VEVENT
BEGIN:VEVENT
SUMMARY:A comparative study of nucleon structure in light-front quark mode
ls in AdS/QCD
DTSTART;VALUE=DATE-TIME:20150921T161000Z
DTEND;VALUE=DATE-TIME:20150921T161000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76678@agenda.infn.it
DESCRIPTION:Speakers: CHANDAN MONDAL (INDIAN INSTITUTE OF TECHNOLOGY KANPU
R)\nWe present the nucleon electromagnetic form factors\, using the light-
front wave functions of a quark-diquark model for the nucleon predicted by
the soft-wall model of AdS/QCD. The results are compared with the soft-wa
ll AdS/QCD model. Then we show a comparitive study of the nucleon charge a
nd anomalous magnetization densities in the transverse plane. Flavor decom
positions of the form factors and transverse densities are also discussed.
We also present a comparison of the generalized parton distributions(GPDs
) calculated in the both models.\n\nhttps://agenda.infn.it/event/9011/cont
ributions/76678/
LOCATION:Laboratori Nazionali di Frascati Hall Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76678/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Canonical Quantization and Lorentz Symmetry for the LC Gauge in QE
D
DTSTART;VALUE=DATE-TIME:20150921T161000Z
DTEND;VALUE=DATE-TIME:20150921T161000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76677@agenda.infn.it
DESCRIPTION:Speakers: Elżbieta Dzimida-Chmielewska (University of Bialyst
ok)\nThe LC gauge condition A_0-A_3=0 is considered within the canonical q
uantization procedure with different temporal parameters: x^0\, x^+ and x^
-\, respectively. Though this gauge condition is Lorentz noncovariant\, th
e symmetry for the Lorentz boost along the x^3 axis remains unbroken. This
longitudinal boost plays a crucial role for the modified quantization pro
cedure at the hypersurface x^{+}=0\, where the standard Dirac procedure fo
r constrained systems fails. The Feynman propagators with chronological or
dering in x^0\, x^+ and x^-\, respectively\, contain the Mandelstam-Leibbr
andt prescription for the noncovariant pole.\n\nhttps://agenda.infn.it/eve
nt/9011/contributions/76677/
LOCATION:Laboratori Nazionali di Frascati Hall Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76677/
END:VEVENT
BEGIN:VEVENT
SUMMARY:True muonium on the light front
DTSTART;VALUE=DATE-TIME:20150924T153000Z
DTEND;VALUE=DATE-TIME:20150924T155000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76676@agenda.infn.it
DESCRIPTION:Speakers: Henry Lamm (Arizona State University)\nThe true muon
ium (μ^+μ^-) bound state presents an interesting test of light-cone quan
tization techniques. In addition to the standard problems of solving thes
e non-perturbative calculations\, true muonium requires correct treatment
of e^+e^- Fock state contributions. Having previously produced a crude m
odel of true muonium using the method of iterated resolvents [1]\, current
work has focused on the inclusion of the box diagrams that should improve
the cutoff dependent issues of the model. Further\, a parallel computer
code allowing for decreased numerical uncertainties is in development. Th
is talk will focus on the current state of these efforts to develop a mode
l of true muonium testable at near-term experiments.\n\n[1] H. Lamm and R.
F. Lebed\, “True Muonium (μ^+μ^−) on the Light Front\,” J. Phys. G
41 125003 (2014).\n\nhttps://agenda.infn.it/event/9011/contributions/7667
6/
LOCATION:LNF\, High Enegy Building n. 36 Aula A1
URL:https://agenda.infn.it/event/9011/contributions/76676/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Light Front Fermion Field Quantization with Explicit Lorentz Symme
try
DTSTART;VALUE=DATE-TIME:20150921T161000Z
DTEND;VALUE=DATE-TIME:20150921T161000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76675@agenda.infn.it
DESCRIPTION:Speakers: Jan Żochowski (University of Białystok)\nA novel q
uantization procedure with the explicit Lorentz symmetry is applied for a
fermion field in $D=3+1$ dimensions. The Wightman function for a free ferm
ion field is evaluated in terms of the covariant singular function $\\Delt
a_{+}(x)$. The singularities at the LF hypersurface $x^{+}=0$ appear whene
ver the "bad" component $\\psi_{-}$ is considered. Accordingly the anti-co
mmutator function cannot follow from the canonical Dirac method for constr
ained systems. The chronological ordering in $x^{+}$ temporal variable lea
ds to the Feynman propagator with a well-known addition of non-covariant t
erm. The Yukawa model in $D=3+1$ dimensions is considered for the Gaussian
effective potential with the \npoint-splitting regularization with a spac
e-like separation.\n\nhttps://agenda.infn.it/event/9011/contributions/7667
5/
LOCATION:Laboratori Nazionali di Frascati Hall Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76675/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Elastic and transition form factors of nucleon resonances in Dyson
-Schwinger Equations
DTSTART;VALUE=DATE-TIME:20150922T094500Z
DTEND;VALUE=DATE-TIME:20150922T101500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76674@agenda.infn.it
DESCRIPTION:Speakers: Jorge Segovia (University of Salamanca)\nThe elastic
and transition form factors of nucleon excited states provide vital infor
mation about their structure and composition. They are a measurable and ph
ysical manifestation of the nature of the hadrons' constituents and the dy
namics that binds them together. In this respect\, two emergent phenomena
of Quantum Chromodynamics (QCD)\, confinement and dynamical chiral symmetr
y breaking\, appear to play an important role\; and Dyson-Schwinger equati
ons (DSEs) have been established as a nonperturbative quantum field theore
tical approach for the study of continuum strong QCD which is able to conn
ect such emergent phenomena with the behaviour of form factors.\n\nIn this
presentation\, I will provide examples of the contemporary application of
DSEs to the study of elastic and transition form factors of N*-states\, p
aying particular attention to the electromagnetic transition form factors
of the nucleon's first radial (the Roper resonance) and first spin (the De
lta resonance) excitations.\n\nIn connection with the proton-Delta transit
ion\, the momentum-dependence of the magnetic transition form factor in th
e Jones-Scadron convention matches that of the nucleon's magnetic form fac
tor once the momentum transfer enters the domain upon which meson-cloud co
ntributions are negligible. From this\, it follows naturally that the Ash
form factor connected with the proton-Delta transition should fall faster
than the nucleon's magnetic form factor. The electric quadrupole ratio (un
like the coulomb ratio) is a keen measure of diquark and orbital angular m
omentum correlations\, the zero in which is obscured by meson-cloud effect
s on the domain currently accessible to experiment.\n\nIn connection with
the proton-Roper transition\, our analysis indicates\nthat the observed Ro
per resonance is at heart of the nucleon's first radial excitation and con
sists of a well-defined dressed-quark core augmented by a meson-cloud that
reduces its (Breit-Wigner) mass by approximately 20%. Our analysis shows
that a meson-cloud obscures the dressed-quark core from long-wavelength pr
obes\; but that it is revealed to probes with moderate and/or large moment
um transfer. This feature is typical of nucleon-resonance transitions\; an
d hence measurements of resonance electro-production on this domain can se
rve as an incisive probe of quark-gluon dynamics within the Standard Model
\, assisting greatly in mapping the evolution between the nonperturbative
and perturbative domains of QCD.\n\nhttps://agenda.infn.it/event/9011/cont
ributions/76674/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76674/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Universality of a New Soft Phase Factor
DTSTART;VALUE=DATE-TIME:20150924T155000Z
DTEND;VALUE=DATE-TIME:20150924T161000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76673@agenda.infn.it
DESCRIPTION:Speakers: Frederik Van der Veken (University of Antwerp)\nThe
Wilson line in a TMD is needed for gauge invariance\, but quantum field th
eory lays no restriction on the specific path layout except for its endpoi
nts. However\, there is no reason to assume that different path structures
would lead to equivalent results. Care has to be taken when splitting com
plicated structures into separate path segments\, especially when the path
contains obstructions such as cusps or self-intersections. We will presen
t a new Wilson line structure that can be considered as a soft factor and
pure phase\, and which is constructed to be universal by definition. This
structure is carefully chosen in order to avoid any obstructions or phase
factors originating from infinity cuts.\n\nhttps://agenda.infn.it/event/90
11/contributions/76673/
LOCATION:LNF\, High Energy Building no 36 Aula Seminari
URL:https://agenda.infn.it/event/9011/contributions/76673/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Light-Front Quantization of the Restricted Gauge Theory of $~QCD_{
2}~$
DTSTART;VALUE=DATE-TIME:20150923T104500Z
DTEND;VALUE=DATE-TIME:20150923T111500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76672@agenda.infn.it
DESCRIPTION:Speakers: Daya Shankar Kulshreshtha (Department of Physics and
Astrophysics\, University of Delhi\, Delhi-110007\, India)\nIn this talk\
, we study the light-front quantization of the restricted gauge theory of
$~QCD_{2}~$ $~\\grave{a}~$ la Cho et al.\, using Hamiltonian\, path integ
ral and BRST quantization procedures.\n\nhttps://agenda.infn.it/event/9011
/contributions/76672/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76672/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Triviality of the light-front vacuum and zero modes
DTSTART;VALUE=DATE-TIME:20150922T133000Z
DTEND;VALUE=DATE-TIME:20150922T140000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76671@agenda.infn.it
DESCRIPTION:Speakers: Wayne Polyzou (The University of Iowa)\nWe use algeb
raic methods to reconcile the triviality of the vacuum in\ndifferent light
-front field theories with the inequivalence of vacuua\nin different canon
ical theories. We show how the inequivalence arises by extending the vacu
um functional from the light-font Fock algebra to\nthe algebra of local ob
servables. This extension leads to an\nidentification of a sub-algebra of
the light-front Fock algebra where\nit is possible to realize Poincar\\'e
invariance and define local\nobservables. While zero modes play no role
in the structure of this\nsub algebra\, they may be needed to treat local
operator products\,\nwhich are in this algebra.\n\nhttps://agenda.infn.it/
event/9011/contributions/76671/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76671/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Parton distribution functions from lattice QCD
DTSTART;VALUE=DATE-TIME:20150924T130000Z
DTEND;VALUE=DATE-TIME:20150924T133000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76670@agenda.infn.it
DESCRIPTION:Speakers: Constantia Alexandrou (University of Cyprus &\; C
yprus Institute)\nRecent results on nucleon observables using simulations
of Quantum Chromodynamics (QCD) with a range of quark masses that include
\ntheir physical values are presented.\nWe use a discretization of the the
ory known as twisted mass QCD\,\nwhich allows for an automatic O(a^2) impr
ovement without \nrequiring improvement of the operators. The simulations
use lattice spacings a\n\nhttps://agenda.infn.it/event/9011/contributions/
76670/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76670/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Asymptotic freedom of gluons in Hamiltonian dynamics
DTSTART;VALUE=DATE-TIME:20150922T143000Z
DTEND;VALUE=DATE-TIME:20150922T145000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76669@agenda.infn.it
DESCRIPTION:Speakers: Maria Gomez-Rocha (University of Graz)\nAsymptotic f
reedom of gluons in QCD is obtained in the leading terms of their renormal
ized Hamiltonian in the Fock space. We calculate the three-gluon interacti
on term in the front-form Hamiltonian for gluons using the renormalization
group procedure for effective particles (RGPEP). The resulting three-gluo
n vertex is a function of the scale parameter\, $s$\, that has an interpre
tation of the size of effective gluons. The corresponding Hamiltonian runn
ing coupling constant\, $g_{\\lambda}$\, depending on the associated momen
tum scale $\\lambda=1/s$\, is calculated in the series expansion in powers
of $g_0=g_{λ_0}$ up to the terms of third order\, assuming some small va
lue for $g_0$ at some large $\\lambda_0$. The third-order QCD solution of
the RGPEP equation to be discussed\, provides an explicit example of how a
symptotic freedom of gluons is exhibited in the scale-dependence of Hamilt
onians as operators in the Fock space.\n\nReferences:\n\n[1] Asymptotic fr
eedom in the front-form Hamiltonian for quantum chromodynamics of gluons\,
\n M. Gomez-Rocha\, S. D. Glazek\, arXiv:1505.06688.\n\n[2] Nonperturb
ative QCD: A Weak coupling treatment on the light front\,\n K.G. Wilson
\, T.S. Walhout\, A. Harindranath\, W.-M. Zhang\, R.J. Perry\, S.D. Glazek
. Phys.Rev. D49 (1994) 6720-6766\n\n[3] Dynamics of effective gluons\,\n
S. D. Glazek\, Phys. Rev. D63\, 116006\, 29p (2001).\n\n[4] Perturbative
formulae for relativistic interactions \n of effective particles\,\n
S. D. Glazek\, Acta Phys. Pol. B43\, 1843\, 20p (2012).\n\nhttps://agend
a.infn.it/event/9011/contributions/76669/
LOCATION:LNF\, High Energy Building n.36 AULA A1
URL:https://agenda.infn.it/event/9011/contributions/76669/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Double parton scattering and 3D proton structure: a light-front an
alysis
DTSTART;VALUE=DATE-TIME:20150921T143000Z
DTEND;VALUE=DATE-TIME:20150921T145000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76668@agenda.infn.it
DESCRIPTION:Speakers: Matteo Rinaldi (PG)\nWe present a calculation of the
effective cross section σ_eff \, an important ingredient in the theoreti
cal description\nof double parton scattering in proton-proton collisions.
The theoretical approach makes use of a Light-Front quark\nmodel as framew
ork to calculate the double parton distribution functions at low-resolutio
n scale. QCD evolution is\nimplemented to reach the experimental resolutio
n scale. The obtained σ_eff \, when averaged over the longitudinal\nmomen
tum fractions of the interacting partons\, x_i in the valence region\, is
consistent with the present experimental\nscenario. However the complete r
esult shows a strong dependence of σ_eff on x_i\, a feature not easily se
en in the\navailable data\, probably because of their low accuracy. Measur
ements of σ_eff in restricted x_i regions are addressed to\nobtain a firs
t indication of double parton correlations\, a novel and interesting aspec
t of the three dimensional structure\nof the nucleon.\n\nhttps://agenda.in
fn.it/event/9011/contributions/76668/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76668/
END:VEVENT
BEGIN:VEVENT
SUMMARY:On non-perturbative renormalization in the truncated Yukawa model
DTSTART;VALUE=DATE-TIME:20150922T130000Z
DTEND;VALUE=DATE-TIME:20150922T133000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76667@agenda.infn.it
DESCRIPTION:Speakers: Vladimir Karmanov (Lebedev Physical Institute)\nIn t
he framework of the Light-Front Tamm-Dancoff method\, we applied the secto
r-dependent renormalization scheme to the quenched Yukawa model. A review
of the results obtained in this way is given. \n The Yukawa model incor
porated spin is studied in the truncation N=3 (one fermion and two mesons)
\, whereas the spinless Yukawa model is truncated up to a higher value N=4
. The eigenvector equation is reduced to a linear system of integral equat
ions for the Fock components. We use the Pauli-Villars regularization. The
following results were found. \n (i) The renormalization removes diver
gences: the results becomes stable relative to increase of the Pauli-Villa
rs masses\, like in the perturbation theory and in contrast to some other
non-perturbative schemes. (ii) Comparison\, in the scalar Yukawa model\, o
f the N=3 and N=4 truncations shows the convergence of the (dominating) lo
w Fock sectors and of the electromagnetic form factor relative to increase
of truncation. This indicates that we are approaching to the true non-per
turbative solution. (iii) In the N=3 truncation\, the determinant of the s
ystem of equations for the Fock components vs. coupling constant $\\alpha$
crosses zero at a critical value $\\alpha=\\alpha_c$. The non-renormalize
d solution obtains a pole ~$1/(\\alpha-\\alpha_c)$. The renormalization of
coupling constant removes also this singularity: the renormalized wave fu
nctions becomes regular at $\\alpha=\\alpha_c$. These properties support t
he expectation that the Light-Front Tamm-Dancoff method complemented with
the sector-dependent renormalization scheme can be an efficient tool in pr
actical finding the non-perturbative solutions in field theory.\n\nhttps:/
/agenda.infn.it/event/9011/contributions/76667/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76667/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Deeply virtual Compton scattering: sensitivities to the three Comp
ton form factors
DTSTART;VALUE=DATE-TIME:20150924T073000Z
DTEND;VALUE=DATE-TIME:20150924T080000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76666@agenda.infn.it
DESCRIPTION:Speakers: Bernard Bakker (VU University)\nIn scalar QED the nu
mber of Compton form factors is known to be five.\nThe case where the inco
ming photon is virtual\, namely produced by\nelectron scattering\, while t
he final photon is real\, the physical\namplitudes depend on only three of
them. We study the sensitivity\nof the differential cross section to the
subleading Compton form factors.\n\nhttps://agenda.infn.it/event/9011/cont
ributions/76666/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76666/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nakanishi representation for two fermions bound state in Minkowski
space.
DTSTART;VALUE=DATE-TIME:20150922T145000Z
DTEND;VALUE=DATE-TIME:20150922T151000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76665@agenda.infn.it
DESCRIPTION:Speakers: Wayne de Paula (Instituto Tecnológico de Aeronáuti
ca)\nWe use the Nakanishi Integral Representation to solve the Bethe-Salpe
ter equation for two fermions bound state with a scalar exchanging\, in Mi
nkowski space. In this formulation we use the Light-Cone projection to obt
ain an equation for the Nakanishi weight function. Further\, we investigat
e the validity of the Nakanishi uniqueness theorem for the weight function
s for the Fermions system.\n\nhttps://agenda.infn.it/event/9011/contributi
ons/76665/
LOCATION:LNF\, High Energy Buiding no36 Aula Seminari
URL:https://agenda.infn.it/event/9011/contributions/76665/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hadron Spectroscopy from Lattice QCD
DTSTART;VALUE=DATE-TIME:20150922T073000Z
DTEND;VALUE=DATE-TIME:20150922T080000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76664@agenda.infn.it
DESCRIPTION:Speakers: Sinead Ryan (Trinity College Dublin)\nI will review
recent progress in lattice hadron spectroscopy with an emphasis on resonan
ces and scattering states. New theoretical ideas will be discussed and res
ults from heavy and light quark systems presented. Some challenges and puz
zles in hadron spectroscopy will be highlighted.\n\nhttps://agenda.infn.it
/event/9011/contributions/76664/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76664/
END:VEVENT
BEGIN:VEVENT
SUMMARY:The pion renormalized light-cone wave function
DTSTART;VALUE=DATE-TIME:20150921T155000Z
DTEND;VALUE=DATE-TIME:20150921T161000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76663@agenda.infn.it
DESCRIPTION:Speakers: Arkadiusz P. Trawinski (University of Warsaw)\nAn ap
proximate light-cone wave function for the pion effective quark-antiquark
Fock sector corresponding to a small value of the renormalization group pa
rameter $\\lambda$ will be presented. This wave function will be used to o
btain wave functions of higher pion sectors for larger $\\lambda$ by the W
-transformation [1].\n\nThe approximate wave function is motivated by the
LF-holography [2] in harmony with the quadratic confinement potential in t
he front form of Hamiltonian dynamics [3]\, and thus also with the linear
confining potential in the instant form. The S-wave and P-wave contributio
ns to the wave functions will be discussed in the context of the pion diff
ractive scattering on platinum\, using the experimental data of the E791 E
xperiment [4].\n\n[1] S. D. Głazek\, Acta Phys. Pol. B42\, 1933 (2011)\n[
2] S. J. Brodsky and G. F. de Téramond\, Phys. Rev. D77\, 056007 (2008)\n
[3] A. P. Trawiński\, et al.\, Phys.Rev. D90\, 074017 (2014)\n[4] E791 Co
llaboration\, Phys. Rev. Lett. 86\, 4768 (2001)\n\nhttps://agenda.infn.it/
event/9011/contributions/76663/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76663/
END:VEVENT
BEGIN:VEVENT
SUMMARY:The renormalization group equations revisited in the light of fini
te field theories.
DTSTART;VALUE=DATE-TIME:20150923T083000Z
DTEND;VALUE=DATE-TIME:20150923T090000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76662@agenda.infn.it
DESCRIPTION:Speakers: Jean-Francois MATHIOT (Laboratoire de Physique Corpu
sculaire)\nThe analysis of physical observables in terms of energy/momentu
m scales necessitates to disantangle spurious scales originating from the
divergence of ill-defined integrals from the physical scales inherent to t
he dynamics of a given system. The use of finite field theories is thus of
particular interest in this separation. We shall investigate this questio
n in the light of the recently proposed Taylor-Lagrange regularization sch
eme applied to light-front dynamics. We calculate the coefficients of the
renormalization group equation in this scheme and compare them with the st
andard derivation using dimensional regularization in different renormaliz
ation schemes. We find that the renormalization group equations should be
mass-dependent in any renormalization scheme\, in contrast to what is usua
lly assumed.\n\nhttps://agenda.infn.it/event/9011/contributions/76662/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76662/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hadron phenomenology from first-principle QCD studies
DTSTART;VALUE=DATE-TIME:20150921T130000Z
DTEND;VALUE=DATE-TIME:20150921T133000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76661@agenda.infn.it
DESCRIPTION:Speakers: Joannis Papavassiliou (Universtiy of Valencia)\nOne
of the longstanding challenges of QCD is to furnish quantitatively\naccura
te ab-initio predictions for the observable properties of hadrons.\nIn thi
s talk we present a significant step for bridging this gap\, based\non the
synergy between Schwinger-Dyson equations and large-volume lattice simula
tions.\n\nhttps://agenda.infn.it/event/9011/contributions/76661/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76661/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gluon TMDs in quarkonia production
DTSTART;VALUE=DATE-TIME:20150924T153000Z
DTEND;VALUE=DATE-TIME:20150924T155000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76660@agenda.infn.it
DESCRIPTION:Speakers: Andrea Signori (VU University Amsterdam / Nikhef)\nP
roduction of quarkonia bound states from hadronic collisions can be a usef
ul handle to map the probability density distributions for gluons inside p
rotons. \nWe derive the factorization theorem for the pT-spectrum of color
-singlet quarkonia production in terms of gluon transverse-momentum-depend
ent parton distribution functions (TMD PDFs). \nWith this tool we predict
cross sections up to NNLL level of accuracy for the LHC and the AFTER@LHC
experiments\, exploring different configurations for the gluon and the tar
get polarization.\nAfter completing a framework in which evolution of TMDs
is incorporated\, we will be able to extract new information about the no
n-perturbative structure of the (un)polarized gluon TMD PDFs from future e
xperimental measurements.\n\nhttps://agenda.infn.it/event/9011/contributio
ns/76660/
LOCATION:LNF\, High Energy Building no 36 Aula Seminari
URL:https://agenda.infn.it/event/9011/contributions/76660/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Pauli-Villars regularization of non-Abelian gauge theories
DTSTART;VALUE=DATE-TIME:20150923T094500Z
DTEND;VALUE=DATE-TIME:20150923T101500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76659@agenda.infn.it
DESCRIPTION:Speakers: John Hiller (University of Minnesota-Duluth)\nAs an
extension of earlier work on QED\, we construct a BRST-invariant Lagrangia
n for SU(N) Yang-Mills theory\, regulated by the inclusion of massive Paul
i-Villars (PV) gluons. The underlying gauge symmetry for massless PV gluo
ns is generalized to accommodate the PV-index-changing currents that are r
equired by the regularization. Auxiliary adjoint scalars are used\, in a
mechanism due to Stueckelberg\, to attribute mass to the PV gluons. The a
ddition of Faddeev-Popov ghosts then establishes a residual BRST symmetry.
Further extension to QCD is also considered. Although there are drawbac
ks to the approach\, in particular the computational load of a large numbe
r of PV fields and a nonlocal interaction of the ghost fields\, this formu
lation could provide a foundation for renormalizable nonperturbative solut
ions of light-front QCD in an arbitrary covariant gauge.\n\nhttps://agenda
.infn.it/event/9011/contributions/76659/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76659/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Light-front $\\phi^4_{1+1}$ theory using a many-boson symmetric-po
lynomial basis.
DTSTART;VALUE=DATE-TIME:20150924T151000Z
DTEND;VALUE=DATE-TIME:20150924T153000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76658@agenda.infn.it
DESCRIPTION:Speakers: Sophia Chabysheva (University of Minnesota-Duluth)\n
We extend earlier work on fully symmetric polynomials for three-boson wave
functions to arbitrarily many bosons and apply these to a light-front ana
lysis of the low-mass eigenstates of $\\phi^4$ theory in 1+1 dimensions.
The basis-function approach allows the resolution in each Fock sector to b
e independently optimized\, which can be more efficient than the preset di
screte Fock states in DLCQ. The approach also allows for a direct calcula
tion of the expectation value of the field.\n\nhttps://agenda.infn.it/even
t/9011/contributions/76658/
LOCATION:LNF\, High Enegy Building n. 36 Aula A1
URL:https://agenda.infn.it/event/9011/contributions/76658/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Parton Distributions and One-Loop Matching
DTSTART;VALUE=DATE-TIME:20150924T145000Z
DTEND;VALUE=DATE-TIME:20150924T151000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76657@agenda.infn.it
DESCRIPTION:Speakers: Xiaonu Xiong (INFN\, Sezione di Pavia\, Pavia\, 2710
0)\nRecent researches showed that the light-cone parton distributions can
be accessed by investigating the quasi distributions which are space-like
correlation functions\, hence can be directly simulated on the lattice. In
this talk\, I will show the one-loop matching between the light-cone and
quasi PDFs\, GPDs. The matching condition is essential to extract the ligh
t-cone distribution from the quasi distributions. I will also discuss the
light-cone and quasi heavy meson distribution amplitude which is perturbat
ively calculable through NRQCD refactorization.\n\nhttps://agenda.infn.it/
event/9011/contributions/76657/
LOCATION:LNF\, High Energy Building no 36 Aula Seminari
URL:https://agenda.infn.it/event/9011/contributions/76657/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hadron Physics from Superconformal Quantum Mechanics in the Light-
Front and its Holographic Embedding
DTSTART;VALUE=DATE-TIME:20150921T123000Z
DTEND;VALUE=DATE-TIME:20150921T130000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76653@agenda.infn.it
DESCRIPTION:Speakers: Guy de Teramond (University of Costa Rica)\nRelativi
stic bound-state equations for mesons and baryons are constructed in a sem
iclassical approximation to light-front QCD from a superconformal algebra
which relates baryon and meson spectra. This procedure uniquely determines
the confinement potential for arbitrary spin and its embedding in AdS spa
ce. The specific breaking of dilatation invariance within the supersymmetr
ic algebra explains hadronic properties common to light mesons and baryons
\, such as the observed mass pattern in the radial and orbital excitation
s\, as well as their distinctive and systematic features. The lowest-lying
state\, the the pi-meson\, is massless in the chiral limit and has no sup
ersymmetric partner. Quark masses break conformal invariance\, but the bas
ic underlying supersymmetric mechanism gives remarkable connections across
the entire spectrum of light and heavy-light hadrons. We also explore the
consequences of extending supersymmetry to double-heavy mesons and baryon
s.\n\nhttps://agenda.infn.it/event/9011/contributions/76653/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76653/
END:VEVENT
BEGIN:VEVENT
SUMMARY:The hadron spectroscopy program at Jefferson Lab
DTSTART;VALUE=DATE-TIME:20150922T080000Z
DTEND;VALUE=DATE-TIME:20150922T083000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76652@agenda.infn.it
DESCRIPTION:Speakers: Raffaella De Vita (GE)\nUnderstanding the hadron spe
ctrum is one of the fundamental issues in modern particle physics. We know
that existing hadron configurations include baryons\, made of three quark
s\, and mesons\, made of quark-antiquark pairs. However most of the mass o
f the hadrons is not due to the mass of these elementary constituents but
to the force that binds them. Studying the hadron spectrum is therefore a
tool to explore one of the fundamental forces in nature\, the strong force
\, and Quantum Chromo Dynamics (QCD)\, the theory that describes it. This
investigation can provide an answer to fundamental questions as what is th
e origin of the mass of hadrons\, what is the origin of quark confinement\
, what are the relevant degrees of freedom to describe these complex syste
ms and how the transition between the elementary constituents\, quarks and
gluons\, and baryons and mesons occurs.\nFor these reasons\, hadron spect
roscopy represents a central part of the Jefferson Lab physics program. In
this talk I will review selected results from the experiments that were c
ompleted during the 6 GeV era of the laboratory life and outline the progr
am planned with the 12 GeV upgrade.\n\nhttps://agenda.infn.it/event/9011/c
ontributions/76652/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76652/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Welcome
DTSTART;VALUE=DATE-TIME:20150921T064500Z
DTEND;VALUE=DATE-TIME:20150921T070000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76651@agenda.infn.it
DESCRIPTION:https://agenda.infn.it/event/9011/contributions/76651/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76651/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Light-front dynamics and the 3He spectral function
DTSTART;VALUE=DATE-TIME:20150924T101500Z
DTEND;VALUE=DATE-TIME:20150924T104500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76650@agenda.infn.it
DESCRIPTION:Speakers: Emanuele Pace (ROMA2)\nAfter the 12 GeV upgrade\, se
veral experiments involving 3He nuclear targets will be performed at JLab
to extract information on the parton structure of the neutron. The parton
transverse momentum distributions (TMDs) (see\, e.g. [1\,2]) in the neutr
on will be studied through polarized SIDIS experiments off 3He\, where a h
igh-energy pion is detected in coincidence with the scattered electron [3]
. To reliably disentangle the nuclear and the partonic degrees of freedom
an accurate theoretical description of the process is needed.\nIn Ref. [4]
the plane wave impulse approximation was adopted. In a recent paper [5] t
he spectator SIDIS process off 3He was studied and the final state interac
tion (FSI) between the hadronizing quark and the detected deuteron was tak
en into account through a distorted spin-dependent spectral function. We a
re now studying the standard SIDIS process\, where the FSI between the obs
erved pion and the remnant is again taken into account through a distorted
spin-dependent spectral function [6}. In these studies the description of
the nuclear dynamics is non-relativistic.\nThis talk addresses an approac
h for the relativistic description of the nuclear dynamics based on the L
ight-front Hamiltonian Dynamics [7]. \nThe key quantity we consider is the
LF spectral function\, where both normalization and momentum sum rule can
be satisfied at the same time. \nPreliminary results will be discussed.\n
Among them\, a study of the role played by relativity in the EMC effect on
3He\, for which JLab data have been taken at 6 GeV [8]. Our final goal is
to evaluate SIDIS cross sections off 3He taking into account both the rel
ativity and the FSI between the observed pion and the remnant\, through ou
r LF spin-dependent spectral function. \n\n\n\nREFERENCES\n\n[1] V. Barone
\, A. Drago\, P. G. Ratcliffe\, Phys. Rept. 359\, 1 (2002). \n[2] A. Bacch
etta et al.\, Phys. Rev. D70\, 117504 (2004). \n[3] G. Cates et al.\, E12-
09-018\, JLAB approved experiment\,\nhallaweb.jlab.org/collab/PAC/PAC38//E
12-09-018-SIDIS.pdf\n[4] S. Scopetta\, Phys. Rev. D 75\, 054005 (2007).\n[
5] L.P. Kaptari\, A. Del Dotto\, E. Pace\, G. Salme` and S. Scopetta\, Phy
s. Rev. C 89\, 035206 (2014).\n[6] A. Del Dotto\, L. Kaptari\, E. Pace\, G
. Salme` and S. Scopetta\, in preparation.\n[7] E. Pace\, G. Salme`\, S. S
copetta\, A. Del Dotto and M. Rinaldi\, Few Body Syst. 54\, 1079 (2013)\;
A. Del Dotto\, L.P. Kaptari\, E. Pace\, G.\, Sergio Scopetta\, Few-Body Sy
st. 55\, 877 (2014).\n[8] J. Seely\, A. Daniel\, D. Gaskell\, J. Arrington
\, N. Fomin\, P. Solvignon\, R. Asaturyan and F. Benmokhtar et al.\, Phys.
Rev. Lett. 103\, 202301 (2009).\n\nhttps://agenda.infn.it/event/9011/cont
ributions/76650/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76650/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Quark-hadron duality: connecting the perturbative and non-perturba
tive QCD regimes
DTSTART;VALUE=DATE-TIME:20150922T101500Z
DTEND;VALUE=DATE-TIME:20150922T104500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76649@agenda.infn.it
DESCRIPTION:Speakers: Simona Malace (Jefferson Lab)\nThe intriguing phenom
enon of quark-hadron duality reflects the non-trivial relationship between
observables at low energies in the region dominated by resonances and tho
se in the deep inelastic \nscattering regime: averaged over the appropriat
e energy intervals the \nbehavior of low-energy observables mimics that of
high-energy\, deep \ninelastic scattering ones. Quark-hadron duality has
been intensively studied as it contains information about the relationship
between the QCD confinement and asymptotic freedom\, about the transition
between the perturbative and non-perturbative regimes in QCD. In this tal
k I will give an overview of the experimental signatures of quark-hadron d
uality and of theoretical approaches to understanding this phenomenon.\n\n
https://agenda.infn.it/event/9011/contributions/76649/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76649/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hadron Reaction and Spectroscopy Studies at JPAC
DTSTART;VALUE=DATE-TIME:20150922T070000Z
DTEND;VALUE=DATE-TIME:20150922T073000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76647@agenda.infn.it
DESCRIPTION:Speakers: Szczepaniak Adam (Indiana University and Jefferson L
ab)\nHadron spectroscopy plays an important role in determining workings o
f QCD. \nI will discuss recent developments in theory and phenomenology a
nd the emerging challenges and opportunities given the forthcoming high pr
ecision data from the Jefferson Lab and other facilities.\n\nhttps://agend
a.infn.it/event/9011/contributions/76647/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76647/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Two-dimensional light-front massless fields and solvable models
DTSTART;VALUE=DATE-TIME:20150923T101500Z
DTEND;VALUE=DATE-TIME:20150923T104500Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76646@agenda.infn.it
DESCRIPTION:Speakers: L. Martinovic ()\nOne of the apparent problems of li
ght front field theory has been a lack of description of two-dimensional m
assless fields. We show how both the massless scalar and fermion fields ca
n be recovered as massless limits of the two-dimensional massive fields an
d consistenly quantized without any loss of physical information. Bosoniza
tion of the ligh-front (LF) fermion field then\nfollows in a straightforwa
rd manner. Solvable models can also be studied directly in the LF formulat
ion.\nWe discuss the operator solution of the Thirring and Thirring-Wess m
odels including the exact (nonperturbative) form of their correlation func
tions. A few remarks concerning the LF Schwinger model and the LF version
of conformal symmetry conclude our contribution.\n\nhttps://agenda.infn.it
/event/9011/contributions/76646/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76646/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Light - Front Wave Function for Hadrons with arbitrary twist
DTSTART;VALUE=DATE-TIME:20150922T151000Z
DTEND;VALUE=DATE-TIME:20150922T153000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76645@agenda.infn.it
DESCRIPTION:Speakers: Alfredo Vega (Universidad de Valparaiso)\nBased on t
he matching of soft wall AdS / QCD models and Light - Front QCD for electr
omagnetic form factors\, we derive a phenomenological wave function for ha
drons with arbitrary twist dimension. We discuss a couple of examples of h
adron properties calculated with this wave function.\n\nhttps://agenda.inf
n.it/event/9011/contributions/76645/
LOCATION:LNF\, High Energy Building n.36 AULA A1
URL:https://agenda.infn.it/event/9011/contributions/76645/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Flavor Asymmetry of the Proton Sea in Chiral Effective Theory
DTSTART;VALUE=DATE-TIME:20150924T083000Z
DTEND;VALUE=DATE-TIME:20150924T090000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76644@agenda.infn.it
DESCRIPTION:Speakers: Chueng-Ryong Ji (NCSU)\nWhile the leading nonanalyti
c behavior in chiral effective theory must be universal\,\nthere has been
a puzzling factor 4/3 difference in the coefficient of the leading nonanal
ytic contribution to the vertex renormalization constant of the nucleon or
equivalently that of the pion for more than a decade. We have recently re
solved this lingering factor difference by carefully analyzing the vertex
renormalization constant with both pseudovector and pseudoscalar coupling
theories and demonstrated how one may correctly achieve the equivalence be
tween these two theories. We discuss this resolution with respect to the p
henomenological application to the flavor asymmetry in the proton sea from
the chiral effective theory. The on-shell splitting function of the pion
from the nucleon has a direct consequence for the analysis of the leading
neutron production at HERA as well as the proposed measurement of tagged d
eep inelastic scattering (TDIS) at JLab.\n\nhttps://agenda.infn.it/event/9
011/contributions/76644/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76644/
END:VEVENT
BEGIN:VEVENT
SUMMARY:T-odd gluon TMDs inside a transversely polarized hadron
DTSTART;VALUE=DATE-TIME:20150924T151000Z
DTEND;VALUE=DATE-TIME:20150924T153000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76643@agenda.infn.it
DESCRIPTION:Speakers: Miguel Echevarria (Nikhef / VU University Amsterdam)
\nThe limit of high gluon density is currently under active investigation\
, both from the theoretical and the experimental side\, since gluons play
an increasingly important role as the energy of the relevant scattering pr
ocess increases. Thus it is our aim to better understand this limit in ord
er to get valuable information on the 3-dimensional structure of hadrons.\
nIn this talk I will analyze the three leading power T-odd gluon TMDs insi
de a transversely polarized target in the perturbative regions\, i.e.\, at
large transverse momentum and the saturation regime. I will show that all
of three gluon TMDs can be dynamically generated by the Qiu-Sterman funct
ion at large transverse momentum. Moreover\, when a close loop gauge link
in the fundamental representation appears in these T-odd gluon TMDs\, they
turn out to be identical at small x\, and can as well be related to the s
pin dependent odderon.\n\nhttps://agenda.infn.it/event/9011/contributions/
76643/
LOCATION:LNF\, High Energy Building no 36 Aula Seminari
URL:https://agenda.infn.it/event/9011/contributions/76643/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Inverting the Nakanishi weight function for a bound-state
DTSTART;VALUE=DATE-TIME:20150923T080000Z
DTEND;VALUE=DATE-TIME:20150923T083000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76642@agenda.infn.it
DESCRIPTION:Speakers: Tobias Frederico (Instituto Tecnologico de Aeronauti
ca)\nWe report our attempts in extracting the Nakanishi weight function fo
r a S-wave bound-state using a model for the Bethe-Salpeter amplitude from
a given form of the weight function. Both the Bethe-Salpeter amplitude i
n Euclidean space and the valence light-front wave function are written in
terms of the Nakanishi integral representation\, and through that we form
ulate an inhomogeneous integral equation problem to solve for the weight f
unction. This linear problem is ill-defined and for the matrix inversion\,
we study the stability of the resulting weight function by truncation on
the small eigenvalues. Reasonable numerical accuracy is found when the wei
ght function is obtained starting from the valence light-front wave functi
on\, while using the Euclidean Bethe-Salpeter amplitude the numerical solu
tion compared with the exact Nakanishi weight function model shows much le
ss accuracy. Our work suggests the possibility to build the Bethe-Salpeter
amplitude from the light-front valence wave function\, which will be use
ful for building covariant models\, e.g.\, for hadrons.\nWork done in coll
aboration with J. Carbonell and V. Karmanov.\n\nhttps://agenda.infn.it/eve
nt/9011/contributions/76642/
LOCATION:Laboratori Nazionali di Frascati Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76642/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Light-Front Quantization of the Vector Schwinger Model \\\\ with a
Photon Mass Term in Faddeevian Regularization
DTSTART;VALUE=DATE-TIME:20150924T145000Z
DTEND;VALUE=DATE-TIME:20150924T151000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76641@agenda.infn.it
DESCRIPTION:Speakers: Usha Kulshreshtha (Department of Physics\, Kirori Ma
l College\, University of Delhi\, Delhi-110007\, India)\nIn this talk\, we
study the light-front quantization of the vector Schwinger model with pho
ton mass term in Faddeevian Regularization\, describing two-dimensional el
ectrodynamics with mass-less fermions but with a mass term for the $ U(1)$
gauge field \\cite{13}-\\cite{15}. This theory is seen to be gauge-non-in
variant (GNI). We then construct a gauge-invariant (GI) theory correspondi
ng to this GNI theory using Stueckelberg mechanism and then recover the ph
ysical content of the original GNI theory from the newly constructed GI th
eory under some special gauge-fixing conditions (GFC's). We then study LFQ
of this new GI theory using Hamiltonian\, path integral and BRST formulat
ions.\n\nhttps://agenda.infn.it/event/9011/contributions/76641/
LOCATION:LNF\, High Enegy Building n. 36 Aula A1
URL:https://agenda.infn.it/event/9011/contributions/76641/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Relaxation of a strongly coupled plasma: a holographic description
DTSTART;VALUE=DATE-TIME:20150921T161000Z
DTEND;VALUE=DATE-TIME:20150921T161000Z
DTSTAMP;VALUE=DATE-TIME:20190217T195827Z
UID:indico-contribution-9011-76640@agenda.infn.it
DESCRIPTION:Speakers: Loredana Bellantuono (BA)\nMethods based on the gaug
e/gravity duality are useful tools for the study of strong interactions ph
enomenology. In particular\, the holographic approach seems effective in d
escribing relaxation processes of strongly coupled systems\, taken initial
ly out of equilibrium. I examine the case of a boost-invariant fluid\, foc
using on the production of a far-from-equilibrium configuration and on the
relaxation to the hydrodynamic regime. A physical realization of this kin
d of system is the strongly-coupled QCD plasma obtained in relativistic he
avy ion collisions. I describe how the effective temperature\, entropy den
sity\, energy density and pressure can be computed\, and analyze their tem
poral evolution. An estimate of the equilibration time is obtained.\n\nhtt
ps://agenda.infn.it/event/9011/contributions/76640/
LOCATION:Laboratori Nazionali di Frascati Hall Aula Bruno Touschek
URL:https://agenda.infn.it/event/9011/contributions/76640/
END:VEVENT
END:VCALENDAR