Prof.
Luciano Maiani
(ROMA1)
12/03/2018, 10:00
Prof.
Paul Hoyer
(University of Helsinki)
12/03/2018, 10:30
Light hadrons are relativistic, strongly bound states with large gluon and sea quark distributions. Interestingly, hadrons also have properties akin to non-relativistic atoms, despite confinement and chiral symmetry breaking. Hadron quantum numbers appear to be determined by the valence quarks only. The quark model is quite successful, especially for quarkonia. The OZI rule and duality provide...
Dr
Piotr Lebiedowicz
(Institute of Nuclear Physics, Polish Academy of Sciences)
12/03/2018, 11:30
We discuss central exclusive diffractive production of light mesons in the reactions $pp \to pp \pi^{+} \pi^{-}$ and $pp \to pp K^{+} K^{-}$ at high energies. The calculation is based on a tensor pomeron model [1] and the amplitudes for the processes are formulated in an effective field-theoretic approach. We include a purely diffractive dipion continuum, the scalar and tensor resonances...
Dr
Maxim Mai
(The George Washington University)
12/03/2018, 12:30
Parameterizing the two-body scattering amplitude by an isobar in each partial wave, we are able to express the three-body scattering amplitude in terms of the isobar propagator and isobar-spectator scattering amplitude in terms of Bethe-Salpeter equation. Analytic properties of all building blocks are determined exactly, imposing three-body unitarity. Subsequently dispersion relations are used...
Dr
Jeff Greensite
(San Francisco State University)
12/03/2018, 14:30
Although color neutrality of the QCD spectrum is the historical definition of confinement, we know that a color neutral particle spectrum is also a feature of gauge-Higgs theories in the Higgs regime, and this means that such theories are also “confining,” at least by the historical definition. In this talk I will suggest that a confinement property stronger than color neutrality, which...
Prof.
Stanley J. Brodsky
(SLAC National Accelerator Laboratory, Stanford University)
12/03/2018, 15:30
A fundamental question in hadron and nuclear physics is how the
mass scale for protons and other hadrons emerges from QCD, even in
the limit of zero quark mass. I will discuss a new approach to the
origin of the QCD mass scale and color confinement based on "lightfront
holography", a formalism which relates the bound-state
amplitudes in the fifth dimension of AdS space to the...
Dr
Gernot Eichmann
(IST Lisboa)
12/03/2018, 16:30
I will present results for light and strange baryons in the Dyson-Schwinger/Bethe-Salpeter approach. Their ground-state properties obtained from three-quark and quark-diquark calculations agree well, and with a few exceptions also the excited-state spectra can be well reproduced and interpreted from their underlying diquark structure. The formalism provides a path towards addressing multiquark...
Giovanni Salme'
(INFN - ROMA)
12/03/2018, 17:00
Recently a new formal tool, based on both the Nakanishi integral representation of the Bethe-Salpeter amplitude and the so called light-front projection, has been adopted for obtaining actual solutions of the Bethe-Salpeter equation. A wide investigation of both spectra and light-cone momentum distributions have been carried on for bound systems with and without spin degrees of freedom, in...
Prof.
Skwarnicki Tomasz
(Syracuse University)
13/03/2018, 09:30
B-factory, charm-factory and hadron-collider experiments have produced evidence for a large number of heavy hadronic structures with unusual properties. We will discuss their experimental signatures, together with underlying uncertainties and future prospects for improvement.
Dr
Jorge Segovia
(Institut de Física d'Altes Energies (IFAE) / Universitat Autònoma de Barcelona (UAB))
13/03/2018, 10:00
The unambiguous establishment of a gluonic spectroscopy (glueballs and quark-gluon hybrids) will change the way we think the matter is constructed: gluons participate at the same level than quarks in building it. This feature is unique in quantum chromodynamics (QCD) and can be traced back to the self-interaction capacity of gluons. It is difficult to single out which states of the hadronic...
Prof.
Adam Szczepaniak
(Indiana University)
13/03/2018, 10:30
I will talk about the S matrix approach to describe 2 and 3 body hadron interactions
Prof.
Eric Swanson
(University of Pittsburgh)
13/03/2018, 12:00
The phenomenology of the LHCb pentaquarks is studied with special attention to the role that hadronic interactions play. Among these are electroweak decays, final state interactions, and one-pion exchange.
Prof.
Enrique Ruiz Arriola
(Universidad de Granada)
13/03/2018, 14:30
We apply the gauge technique to conserved currents and look for the consequences for bound states.
Dr
Savvas Zafeiropoulos
(Universität Heidelberg)
13/03/2018, 15:00
Ioffe-time distributions, which are functions of the Ioffe-time ν, are the Fourier transforms of parton distribution functions with respect to the momentum fraction variable x. These distributions can be obtained from appropriate equal time, quark bilinear hadronic matrix elements which can be calculated from first principles via lattice QCD methods. Here, we present the first numerical...
Elena Santopinto
(INFN)
13/03/2018, 15:30
Theoretical predictions on hybrid and pentaquark spectroscopy will be presented and discussed
Prof.
Feng-Kun Guo
(Institute of Theoretical Physics, CAS)
13/03/2018, 16:30
Since the discovery of the D_{s0}^*(2317) and the D_{s1}(2460) in 2003, there have been 3 puzzles in the spectroscopy of positive-parity charm mesons: (1) why are the D_{s0}^*(2317) and D_{s1}(2460) masses much lower than the quark model predictions for the lowest positive parity charm mesons? (2) why is the mass difference between the D_{s0}^*(2317) and the D_{s1}(2460) is equal to that...
Prof.
Anna Hasenfratz
(University of Colorado)
14/03/2018, 10:30
Beyond Standard Model theories describing the electro-weak sector
with a 125 GeV Higgs boson but with so far no other observed resonances must be consistent with large scale separation or “walking". Large separation of scales arises naturally and in a tunable manner in mass-split models that are built on a conformal fixed point in
the ultraviolet. When the fermion masses are split, with...
Oliver Witzel
(University of Colorado Boulder)
14/03/2018, 11:30
Using the specific example of four light and eight heavy flavors we
explore mass-split models using fully dynamical numerical simulations.
We present results for the meson spectrum showing states made up of
only light or only heavy flavors in order to verify theoretical
expectations. With results obtained at two values of the bare gauge
coupling, five different values for the mass of...
Massimo D'Elia
(PI)
14/03/2018, 12:00
We discuss recent lattice results concerning the influence of
external backgrounds, such as magnetic fields and chemical potentials,
on the confining and screening properties of the QCD thermal medium.
Joao Penedones
(EPFL)
14/03/2018, 12:30
Inspired by the recent success of the numerical approach to the conformal bootstrap, we revisit the S-matrix bootstrap program. We shall explain how to obtain analytic bounds on the interaction strength in 1+1 QFT. In higher dimensions, we propose a numerical algorithm that seems to converge to optimal bounds.
Dr
Luca Zambelli
(TPI, Friedrich-Schiller-Universität Jena)
14/03/2018, 14:30
The functional renormalization group is a nonperturbative semi-analytic tool for continuum computations in quantum field theory and high energy theory, and I will present some illustrative examples of its modern applications. It has been quite successful in describing chiral symmetry breaking and quantum criticality in three dimensional fermionic systems, as I will briefly review with some...
Giuliano Panico
(IFAE (BArcelona))
14/03/2018, 15:00
One main obstacle for any BSM scenario solving the hierarchy problem is its potentially large contributions to electric dipole moments. An elegant way to avoid this problem is to have the light SM fermions couple to the BSM sector only through bilinears. This possibility can be neatly implemented in composite Higgs models by dynamically generating the fermion Yukawa couplings at different...
Prof.
Jose Pelaez
(Universidad Complutense de Madrid)
15/03/2018, 09:30
I present here some recent results we obtained by applying dispersion relations and other methods based on analyticity on the complex plane, to determine scattering amplitudes with pions and kaons from data and to determine resonance parameters.
Matthew Shepherd
(Indiana University)
15/03/2018, 10:00
If one examines the rules for constructing hadrons as suggested by the QCD Lagrangian, there is no obvious reason why nature should be limited to just quark-antiquark mesons and three-quark baryons. In the last decade, numerous new experimental results, primarily for hadrons containing charm quarks, suggest that the hadron spectrum may in fact contain more complex constructions of quarks and...
Mr
Jannes Nys
(Ghent University)
15/03/2018, 10:30
We have conducted studies on the production mechanism of various channels, which are being analyzed at Jefferson Lab. These include pseudoscalar and vector meson production. Using the constraint of analyticity of the amplitudes, we are able to propagate experimental information from one energy regime to the other. This approach relates properties of the baryon spectrum to the dynamics of meson...
Mr
Boris Grube
(Technische Universität München)
15/03/2018, 11:30
COMPASS is a multi-purpose fixed-target experiment at the CERN Super Proton Synchrotron aimed at studying the structure and spectrum of hadrons. One of the main goals of the experiment is the study of the light-meson spectrum. In diffractive reactions with a 190 GeV/c negative pion beam, a rich spectrum of isovector mesons is produced. The resonances decay typically into multi-body final...
Mr
Malwin Niehus
(HISKP, University of Bonn)
15/03/2018, 12:00
Usually the simulation of scattering processes in lattice QCD is carried out at unphysical high values of the quark masses [1]. Hence, a method to extrapolate data obtained in lattice calculations to physical masses is needed to allow for comparison between theory and experiment. To obtain a sound extrapolation, dispersion relations and chiral perturbation theory can be invoked. While a simple...
Alessandro Pilloni
(ROMA1)
15/03/2018, 12:30
I will discuss some recent development in amplitude analysis to improve the description of exotic states
Prof.
Raul Briceno
(ODU & JLab)
15/03/2018, 14:30
The non-perturbative nature of quantum chromodynamics (QCD) has historically left a gap in our understanding of the connection between the fundamental theory of the strong interactions and the rich structure of experimentally observed phenomena. For the simplest properties of stable hadrons, this can now be circumvented using lattice QCD. In this talk I discuss a path that will allow us to...
Dr
Christopher Thomas
(University of Cambridge)
15/03/2018, 15:00
I will discuss recent progress in studying excited and exotic mesons using first-principles lattice QCD calculations, an area where there have been significant advances in the last few years. In particular, some results on excited mesons, resonances and related phenomena in the light and heavy sectors will be highlighted, including work on heavy tetraquarks, open-charm mesons and light scalar...
Prof.
John Bulava
(University of Southern Denmark, CP3-Origins Institute)
15/03/2018, 15:30
I will review the methods used to calculate two-hadron scattering
amplitudes from lattice QCD. Particular emphasis will be placed on controlling the various systematic errors inherent in such calculations, such as those due to the lattice spacing and finite volume. As illustrative examples, I will discuss recent and ongoing results for amplitudes containing the rho(770), K*(892),...
Dr
Francesco Giacosa
(Institut für Theoretische Physik, Johann Wolfgang Goethe-Universität, Frankfurt)
15/03/2018, 16:30
A standard quark-antiquark state gets dressed by meson-meson clouds
corresponding to its decay product and its pole moves down in the complex
plane. If some conditions are met (coupling constant strong enough nearby
energy threshold(s)), additional. so-called companion poles may emerge, which
correspond to a type of dynamically generated states. For instance, the light
scalar states...
Dr
Arkadiusz TRAWINSKI
(CEA)
16/03/2018, 09:30
The expectation value of the quantum energy-momentum tensor (EMT) for an unpolarized proton target in the Breit frame can be matched with an anisotropic perfect fluid EMT. This matching offers the possibility of interpreting the EMT form factors in terms of the internal energy and transverse/radial pressure inside an unpolarized proton target.
The generalization of this result to a more...
Mr
Tobias Isken
(HISKP, University of Bonn)
16/03/2018, 10:00
I will present a dispersive analysis of mesonic 3-body decay amplitudes based on the fundamental principles of analyticity and unitarity. In this framework the leading final-state interactions are fully taken into account.
The first part of the talk will focus on the $\eta^\prime\to\eta\pi\pi$ decay channel [arXiv:1705.04339 [hep-ph]]. This decay offers several features of interest: due to...
Prof.
Christian Fischer
(JLU Giessen)
16/03/2018, 10:30
We summarize recent results on the spectrum (and form factors) of conventional
and exotic meson states in the DSE/BSE framework. We contrast states with
conventional and exotic quantum numbers and outline the ability of the framework
to accommodate for glueball, hybrid and four-quark states.
Dr
Helios Sanchis Alepuz
(University of Graz)
16/03/2018, 11:30
The calculation of hadronic observables using a combination of Dyson-Schwinger and Bethe-Salpeter equations has developed dramatically in recent years. The method aims at the calculation of hadronic properties
from the underlying QCD degrees of freedom, without abandoning the realm of continuum quantum field theories.
We report on the most recent calculations of the spectrum and...
Prof.
Joannis Papavassiliou
(University of Valencia-IFIC)
16/03/2018, 12:00
The dressed gluon-quark vertex is a fundamental ingredient of the kernels appearing in the one- and two-body problems.
We present a novel representation of this vertex in terms
of the gluon-quark scattering matrix, and develop a method capable of
elucidating a quark-antiquark Bethe-Salpeter kernel that is symmetry-consistent with a given quark gap equation.
A main advantage of this...
Dr
Daniele Binosi
(ECT*-Fondazione Bruno Kessler)
16/03/2018, 12:30
The dynamics leading to the formation of coloured composite massless excitations in Yang-Mills theory is interlocked with the one leading to the generation of a gluon mass scale in the infrared. I will discuss how the Bethe-Salpeter equation leading to the former structures is coupled to the Schwinger-Dyson equation leading to the latter phenomenon, paying particular attention to the...
Prof.
Thomas DeGrand
(University of Colorado)
I'll describe lattice spectroscopy of SU(N) gauge theories with N in the range 2-7, with a small number
of fermion degrees of freedom. These are systems which are most similar to QCD: they are confining
and chirally broken. The simple states are s-wave mesons and baryons.
Specific systems I have studied are SU(N) gauge theories, quenched or with Nf=2 fundamental quarks
and SU(4) with two...
