PHIPSI13 - International Workshop on e+e- collisions from Phi to Psi 2013

9 Sept 2013, 08:30 → 12 Sept 2013, 18:55 Europe/Rome

Aula Amaldi (Dip. di Fisica - "Sapienza" Universita' di Roma - G. Marconi building)

Graziano Venanzoni (LNF), Paolo Gauzzi (ROMA1)

PHIPSI13 Workshop will be held in Rome, at Physics Department of "Sapienza University" from September 9th, 2013 to September 12th, 2013.

Monday 9 September

Registration

Opening

R-measurement (I)

1 Selected implications of an R-scan between 3GeV and 4.5GeV for charm physics

Precise determinations of the cross section between 3 GeV and 4.5GeV as planned in the near future at BESS III can provide an important input for an improved determination of the charmed quark mass. The necessary experimental and theoretical ingredients are presented. As a second topic the possibilities for direct resonant production of chi_c1 and chi_2 in electron-positron annihilation at BESS III will be explored and possible backgrounds will be studied.

Speaker: Prof. Johann Kuehn (KIT, Karlsruhe)

Slides Kuehn_PHI-PSI_2013.pdf

2 Hadronic cross section measurement at CMD3

Speaker: Dr Ivan Logashenko

Slides PhiPsi2013Logashenko.pdf

3 Hadronic cross section measurement at SND

Speaker: Dr Tatyana Dimova

Slides PhiPsi.pdf PhiPsi.pptx

4 Hadronic cross section at BaBar

Speaker: Dr Eugeny Solodov

Slides Solodov_PhiPsi2013_BaBar.pdf

5 Measurement of the hadronic cross section at KLOE/KLOE-2

Speaker: Anthony Palladino Jr (LNF)

Slides phipsi2013_ap.pdf

10:55 Coffee break

Symmetries (I)

6 MEG results and prospects

The field of Charged Lepton Flavor Violation (CLFV) is very interesting since it permits clear background-free observations of physics beyond the SM, with an extended reach with respect to LHC searches. The MEG experiment has been searching for the Standard-Model suppressed decay $\mu \to e + \gamma$ with unprecedented sensitivity. Its last result is an upper limit on the $\mu \to e \gamma$ Branching ratio of 5.7x10^{-13} and has still room for improving it thanks to its final 2013 run. To go further with the sensitivity an upgrade is being prepared in order to improve the experimental apparatus and reach the 10^{-14} range. This will constraint several models proposed to extend the SM. Other experiments are searching for different CLFV processes and a more complete picture of the Flavor Physics will be available in the next years, leading to more detailed knowledge of beyond-SM physics.

Speaker: Simeone Dussoni (PI)

Slides PHIPSI_DUSSONI_Meg.pdf

7 Lepton Flavour Violation beyond the present limits

Speaker: Dr Lorenzo Calibbi

Slides calibbi_phipsi13.pdf

8 Dark force searches in fixed target experiments

Speaker: Marco Battaglieri (GE)

Slides battaglieri_phipsi13.pdf

9 Recent KLOE results on the search for dark forces

Speaker: Enrico Graziani (ROMA3)

Slides graziani.pptx

10 Lepton mixing under the lepton charge nonconservation, neutrino masses and oscillations and the "forbidden" decay mu- --> e- + gamma

The lepton-charge ( Le , Lmu , Ltau ) nonconserving interaction leads to the mixing of the electron, muon and tau neutrinos, which manifests itself in spatial oscillations of a neutrino beam, and also to the mixing of the electron, negative muon and tau lepton, which, in particular, may be the cause of the "forbidden" radiative decay of the negative muon into the electron and gamma quantum. Under the assumption that the nondiagonal elements of the mass matrices for neutrinos and ordinary leptons, connected with the lepton charge nonconservation, are the same, and by performing the joint analysis of the experimental data on neutrino oscillations and experimental restriction for the probability of the decay mu- --> e- + gamma per unit time, the following estimate for the lower bound of neutrino mass has been obtained: m_{ \nu } > 1.5 eV / c^2

Speaker: Dr Valery Lyuboshitz (Joint Institute for Nuclear Research ( Dubna ))

Slides PHI_PSI_13--Valery_Lyuboshitz_1.pdf PHI_PSI_13--Valery_Lyuboshitz_1.ppt

13:05 Lunch

Gamma-gamma Physics

11 Gamma-gamma physics at KLOE/KLOE-2

Speaker: Danilo Babusci (LNF)

Slides PhiPsi13_Babusci.pdf

12 Gamma-gamma physics at BELLE

We report a high-statistics measurement of the differential cross section of the process gamma gamma --> Ks Ks with the Belle detector. We study spectroscopy of light-quark resonances and charmonia and test QCD models using the data. We summarize our systematic measurements of different processes of gamma gamma --> meson pair production based on the parameterization of the cross sections and comparison with QCD models. We report also on the measurement of the two-photon pi0 transition form factor at Belle.

Speaker: Dr Sadaharu Uehara

Slides phipsi13_tp_belle.pdf phipsi13_tp_belle.ppt

13 The anomalous process gamma pi --> pi pi and its impact on the pi^0 transition form factor

The process gamma pi --> pi pi, in the limit of vanishing photon and pion energies, is determined by the chiral anomaly. This reaction can be investigated experimentally using Primakoff reactions, as currently done at COMPASS. We derive a dispersive representation that allows to extract the chiral anomaly from cross-section measurements up to 1 GeV, where effects of the rho resonance are included model-independently via the pi-pi P-wave phase shift. We discuss how this amplitude serves as an important input to a dispersion-theoretical analysis of the pi^0 transition form factor, which in turn is a vital ingredient to the hadronic light-by-light contribution to the anomalous magnetic moment of the muon.

Speaker: Prof. Bastian Kubis (University of Bonn)

Slides Kubis_PhiPsi13.pdf

14 Eta and eta_prime transition form factors from rational approximants

Speaker: Rafel Escribano (Universitat Autònoma de Barcelona)

Slides PHIPSI13_Escribano.pdf

15:45 Coffee break

Measurement and Theoretical Evaluation of g-2 (I)

15 Unified dispersive approach to gamma* -> gamma pi pi and gamma gamma -> pi pi at low energy

We discuss how to generalize the classic results on photon-photon scattering which combine dispersion theoretical constraints with chiral symmetry and soft photon theorems to the photon-photon*(q^2) scattering amplitude into a pion pair. This generalisation requires a specific treatment of resonance exchange diagrams. The constructed amplitude displays explicitly the dependence on pi-pi phase-shifts, pion electromagnetic form factors (being also sensitive to the omega-pi form factor puzzle) and pion polarizabilities. It is matched to the NLO ChPT amplitude near zero energies and compared to experimental measurements of e^+ e^- -> gamma pi0 pi0 by SND and CMD-2 below one GeV. Applications are made to the pions generalized polarizabilities, to the sigma meson (pole) electromagnetic form factor and to the gamma pi pi contribution to the HVP and the muon g-2.

Speaker: Dr Bachir Moussallam (IPN, Universite Paris-Sud)

Slides moussallam_phipsi13.pdf

16 Virtual photon-photon scattering

We present a formalism for the scattering of two photons into a pion pair based on dispersion relations in combination with unitarity, chiral symmetry, and soft-photon constraints. In particular, we discuss the complications that arise due to the analyticity properties of the amplitude if both photons are off-shell, and argue that the dispersive framework can be extended to remain valid even in that case. Such a representation is crucial input for a reduction of model dependence in the light-by-light scattering contribution to the anomalous magnetic moment of the muon.

Speaker: Dr Martin Hoferichter (University of Bern)

Slides PhiPsi_hoferichter.pdf

17 The light-by-light contribution to the muon (g-2) within nonlocal chiral quark model

The light-by-light contribution to the anomalous magnetic moment of muon is calculated in the framework of the nonlocal chiral quark model. The contributions from pseudoscalar and scalar resonances and nonresonance contact terms are included. Full kinematic dependence of vertices with off-shell photons and mesons in intermediate states in the light-by-light scattering amplitude is taken into account. The limit of local quark model is discussed.

Speaker: Dr Andrey Radzhabov (The Institute for System Dynamics and Control Theory of Siberian Branch of Russian Academy of Sciences)

Slides RadzhabovRome.pdf

Monte Carlo and Radiative Corrections

18 Status of Monte Carlo generators for energy scan ans radiative return

Speaker: Dr Henryk Czyz

Slides czyz_phipsi2013.pdf

19 Status of Monte Carlo generators for gamma-gamma physics

Speaker: Mr Sergiy Ivashyn (ITP NSC KIPT (Kharkiv))

Slides Ivashyn_PhiPsi13.pdf

20 Final state Coulomb interaction and asymmetry of pair production close to threshold in $e^+e^-$ annihilation.

We investigate a contribution of the $d$ wave to the cross section of $e^+e^-$ annihilation to the pair of charged leptons or nucleons close to threshold of the process. In contrast to the point of view accepted in literature, due to the Coulomb final state interaction this contribution does not vanish even at zero relative velocity of produced particles. This results in the nonzero asymmetry in angular distribution at threshold. Though value of the asymmetry is small, observation of this effect is not hopeless.

Speaker: Prof. Vladimir Dmitriev (Budker Institute of Nuclear Physics)

Slides Dmitriev.pdf

18:30 Welcome cocktail

Tuesday 10 September

Measurement and Theoretical Evaluation of g-2 (II)

21 Progress on the new g-2 experiment at FNAL

Speaker: Dr Stephen Maxfield

Slides Maxfield_SJM_PhiPsi2013_g-2_E989.pptx

22 Status and prospects of the muon g-2 experiment at J_PARC

Speaker: Dr Katsuhiko Ishida

Slides muon_g-2_Ishida.pdf

23 Status of Standard Model calculation of lepton g-2

Speaker: Dr Marc Knecht

Slides Knecht_PhiPsi_2013.pdf

24 Hadronic vacuum polarisation in g-2 and alpha_QED

The Standard Model prediction of the anomalous magnetic moment of the muon is reviewed with emphasis on the hadronic vacuum polarisation contributions. The current status of these corrections is described, different evaluations are compared and future prospects for further reducing the error are discussed. Also discussed are the hadronic contributions to the running of the QED coupling and their role for g-2.

Speaker: Dr Thomas Teubner (University of Liverpool)

Slides tteubner_phipsi13.pdf

10:25 Coffee break

R-measurement (II)

25 e+e- hadron production cross section at BELLE

A number of production cross sections for electron-positron annihilation to hadronic final states have been measured using the Belle data set. This is possible given that the Belle detector is a general purpose detector with a large solid angle coverage. The cross section measurements predominantly fall into two categories: cross sections at, or near, the machine operating energy, and cross sections over a range of energy bins produced via initial-state radiation. Cross section measurements can be used in the studying of hadron spectroscopy, as well as providing checks for the development of Quantum Chromodynamic models. The Belle data still provides the opportunity for the systematic measurement of low-energy, below 3 GeV, cross sections. These low-energy cross sections can be used in the calculation of the leading-order Hadronic Vacuum Polarization contributions to the muon anomalous magnetic moment and the running of alpha.

Speaker: Dr Jason Crnkovic

Slides belle-sigma-phipsi13-crnkovic.pdf

26 Hadronic cross section measurement at BESIII

Speaker: Dr Sven Schumann

Slides Sven_neu.pdf

27 Pion form factor and reactions $e^+e^-\to\omega\pi^0$ and $e^+e^-\to\pi^+\pi^-\pi^+\pi^-$ at energies up to 2 -- 3 GeV in the many-channel approach.

Using the field-theory-inspired expression for the pion electromagnetic form factor $F_\pi$, a good description of the data in the range $-10<s<1$ GeV$^2$ is obtained upon taking into account the pseudoscalar-pseudoscalar (PP) loops. When the vector-pseudoscalar (VP) and the axial vector-pseudoscalar (AP) loops are taken into account in addition to the PP ones, a good description of the BABAR data on the reaction $e^+e^-\to\pi^+\pi^-$ is obtained at energies up to 3 GeV. The inclusion of the VP and AP loops demands the treatment of the reactions $e^+e^-\to\omega\pi^0$ and $e^+e^-\to\pi^+\pi^-\pi^+\pi^-$. This task is also made, with the SND data on the $\omega\pi^0$ production and the BABAR data on the $\pi^+\pi^-\pi^+\pi^-$ production, both in $e^+e^-$ annihilation, upon taking into account $\rho(770)$ and the heavier $\rho(1450)$, $\rho(1700)$, $\rho(2100)$ resonances. The problems with inclusion of the VP and AP loops are pointed out and discussed.

Speaker: Arkadii Kozhevnikov (Lab. Theoretical Physics, Sobolev Inst. of Mathematics)

Slides kozhevnikov_Jpsi13.pdf

Machines and Detectors (I)

28 The IRIDE project

Speaker: Massimo Ferrario (LNF)

Slides IRIDE_PHIPSI13.pptx.pdf

29 Low-energy electron physics at MAMI

Speaker: Dr Achim Denig

Slides Denig.pdf

30 Meson spectroscopy at JLAB at 12 GeV

Speaker: Dr Stuart Fegan

Slides SFegan_PHIPSI2013.pdf

13:05 Lunch

Poster session

31 Analytic continuation of nucleon form factors in the time-like region.

Using the Skyrme model for nucleons we test the possibility of determining nucleon form factors in the time-like region by an analytic continuation of space-like form factors with particular attention to the behavior at the nucleon-antinucleon production threshold.

Speaker: Simone Moretti (PG)

32 Combined analysis of BES and KEDR data on psi(3770)

The available data on the D-D-bar cross section and the inclusive hadronic cross section in the psi(3770) region by BABAR, BELLE, BES, CLEO and KEDR experiments were analyzed assuming that the systematic uncertainties in cross sections measured by different detectors are not correlated. The three theoretical models were employed for the data analysis. The first model implies that the D-D-bar production amplitude is the sum of the psi(3700), psi(2S) and smooth nonresonant contributions and that the resonant contributions have the Breit-Wigner shape with the commonly used assumption on the energy-dependent width. The psi(3770) parameters obtained with are close to those recently published by the KEDR collaboration. Alternatively, the models suggested by N.N. Achasov and G.N. Shestakov and by G.-Y. Chen and Q. Zhao were used in the analysis of cross sections.

Speaker: Dr Andrey Shamov (Budker INP)

33 Comparative study of the production of scalar and tensor mesons in e+e- collisions

The intensity of scalar $a_0(980)$, $f_0(980)$ and tensor $a_2(1320)$, $f_2(1270)$ mesons production at VEPP-2000 (BINP, Novosibirsk) and, possibly, the upgraded DA$\Phi$NE (Frascati, Italy) in the processes $e^+e^- \to a_0 (f_0$, $a_2$, $f_2) \gamma$ is calculated with the help of VDM and the kaon loop model (for scalar mesons case). The processes $e^+e^-\to a_2(f_2)\gamma$ have not been seen in the energy region $1.5-2.0$ GeV. It turned out that at this energies $\sigma(e^+e^-\to a_2(f_2)\gamma)\sim 10$ pb and $\sigma(e^+e^-\to a_0(f_0)\gamma)\sim 0.1$ pb. Photon angle distribution, the spin density matrices of $a_2$ and $f_2$ and the background situation will be reported also

Speaker: Mr Alexey Kiselev (Sobolev Institute for Mathematics)

34 Determination of the magnetic dipole moment of the rho meson

We determine the magnetic dipole moment of the rho meson using preliminary data from the BaBar Collaboration for the $e^{+} e^{-} \to \pi^+ \pi^- 2 \pi^0$ process, in the center of mass energy range from 0.9 to 2.2 GeV. We describe the $\gamma^* \to 4\pi$ vertex using a vector meson dominance model, including all intermediate resonance contributions. We find that ${\mu}_\rho = 2.1 \pm 0.5 \: [e/2 m_\rho]$. In addition, we obtain the branching ratio $BR(\rho^0 \to \pi^+ \pi^- 2 \pi^0 ) = 1.7 \pm 0.6 \times 10^{-5} $.

Speaker: Dr Genaro Toledo Sanchez (UNAM)

35 Dispersion theory methods for transition form factors: from $\omega/\phi\to\pi^0\gamma^*$ to $e^+e^-\to\pi^0\gamma$

Dispersion theoretical analyses of transition form factors are stepping stones to a model-independent determination of the light-by-light scattering contribution to $(g-2)_\mu$. We have performed such an analysis on the conversion decays of the lightest isoscalar vector mesons, $\omega/\phi\to\pi^0\ell^+\ell^-$. For that we resort to a dispersive analysis of the $V\to3\pi$ partial-wave amplitude and the precisely constrained pion vector form factor as main ingredients. Extending the framework for the vector decays to incorporate the intermediate $e+e-\to3\pi$ we obtain a description of the $\pi^0$ transition form factor measured in $e^+e^-\to\pi^0\gamma$.

Speaker: Dr Sebastian P. Schneider (HISKP Uni Bonn)

36 Impact of gammaV-vertex corrections on the VPgamma transition form factors

Speaker: Mr Sergii Raspopov

Poster Raspopov.pdf

37 On the spin correlations of muons and tau leptons generated in the annihilation processes e+e- ->mu+ mu-, e+e- ->tau+ tau-

Using the technique of helicity amplitudes, the electromagnetic process e+e- --> mu+mu- is theoretically investigated in the onephoton approximation. The structure of the triplet states of the final mu+mu- system is analyzed. It is shown that in the case of unpolarized electron and positron the final muons are also unpolarized, but their spins are strongly correlated. Explicit expressions for the components of the correlation tensor of the final mu+mu- system are derived. The formula for the angular correlation at the decays of final muons mu+ and mu-, produced in the process e+e- --> mu+mu- is obtained. It is demonstrated that spin correlations of muons in the process of electronpositron pair annihilation have the purely quantum character, since one of the Bell type incoherence inequalities for the correlation tensor components is always violated. The additional contribution of the weak interaction of lepton neutral currents through the virtual Z boson is considered it is established that, taking into account the weak interaction, the qualitative character of the muon spin correlations does not change. Analogous consideration can be wholly applied as well to the final tau leptons formed in the process e+e- --> tau+tau-

Speaker: Dr Valery Lyuboshitz (Joint Institute for Nuclear Research ( Dubna ))

Slides PHI_PSI_13--Valery_Lyuboshitz_2.pdf

38 Precision measurement of the charged Ke4(+-) decay (K+- to pi+ pi- e+- nu) and study of the charged Ke4(00) decay (K+- to pi0 pi0 e+- nu)

The NA48/2 collaboration has analyzed 1.13 million charged kaon decays Ke4(+-) to pi+ pi- e nu leading to an improved determination of the Branching Fraction at percent level precision and detailed form factor studies. The hadronic form factors in the S- and P-wave and their variation with energy are obtained concurrently with the phase difference between the S- and P-wave states of the pi pi system. The latter measurement allows a precise determination of a00 and a02, the I=0 and I=2 S-wave pi pi scattering lengths. A combination of this result with another NA48/2 measurement, obtained in the study of K± →pi0 pi0 pi± decays, brings a further improved determination of a00 and the first precise experimental measurement of a02. These measurements bring new inputs to low energy QCD calculations and are crucial tests of existing predictions from Chiral Perturbation Theory and lattice QCD calculations. The NA48/2 collaboration has accumulated ~66000 semi-leptonic charged kaon decays Ke4(00) to pi0 pi0 e nu, increasing the world available statistics by several orders of magnitude. Background contamination at the one percent level and very good pi0 reconstruction allow the first accurate measurement of the Branching Fraction and decay Form Factor. The achieved precision makes possible the observation of small effects such as a deficit of events at low pi0 pi0 invariant mass which can be explained by charge exchange rescattering in the pi pi system below the 2 m(pi+) threshold. Future prospects include the observation of several ~1000 decays in similar muonic modes Kmu4(00) (never observed) and Kmu4(+-) (7 events observed). Such poorly known modes could be studied also in the forthcoming NA62 experiment currently under construction.

Speaker: Mauro Raggi (LNF)

39 Radiative pi-gamma transitions of excited light-quark mesons in the covariant oscillator quark model

The COMPASS collaboration, as a part of their hadron spectroscopy program, will measure the radiative decay widths of the light-quark mesons via the Primakoff reactions. In this work we study the photon couplings of light qqbar states applying the covariant oscillator quark model and evaluate the rates for the transitions; {rho, b1(1235), a1(1260), a2(1320), pi2(1670), rho3(1690), rho(1700)} -> pi gamma, which can be measured in the experiments. Forthcoming results from the COMPASS will make these predictions to verify.

Speaker: Dr Tomohito MAEDA (Nihon University)

40 Spin correlations of the final leptons in the two-photon processes gamma gamma -> e+e-, mu+mu-, tau+ tau-

The spin structure of the two-photon process gamma gamma --> e+ e- is theoretically investigated. It is shown that if the primary photons are unpolarized the final electron and positron are unpolarized as well but their spins are strongly correlated. Explicit expressions for the components of the correlation tensor of the final e+e- system are derived and the relative fractions of singlet and triplet states of the e+e- pair are found. It is demonstrated that in the process gamma gamma --> e+e- one of the incoherence inequalities of the Bell type for the correlation tensor components is always violated and thus spin correlations of the electron and positron in this process have the strongly pronounced quantum character. Analogous consideration can be wholly applied as well to the two-photon processes gamma gamma -->mu+mu- and gamma gamma -->tau+tau- which become possible at considerably higher energies

Speaker: Dr Valery Lyuboshitz (Joint Institute for Nuclear Research ( Dubna ))

Slides PHI_PSI_13--Valery_Lyuboshitz_3.pdf

41 Status of the hadronic light-by-light scattering in the muon g-2

We give an update on the current status of the hadronic light-by-light scattering contribution to the muon g-2. We review recent work by various groups, list some of the open problems and give an outlook on how to better control the uncertainty of this contribution. This is necessary in order to fully profit from planned future muon g-2 experiments to test the Standard Model.

Speaker: Dr Andreas Nyffeler

Poster Poster_Nyffeler.pdf

42 Study of \psi(2s)->\mu^+\mu^- decay with KEDR detector

Since 2004 KEDR detector at VEPP-4M collider has taken several data sets in psi(2s) region, acquiring total luminosity of about 7 pb^{-1}, which corresponds to more than 3.5 \times 10^6 psi(2s). There were 5 scans of the resonance allowing us to know the collider's energy spread and 5 runs where the data was taken at the psi(2s) peak and slightly below it. We report the value of \Gamma_{ee}\times B_{\mu\mu} = 20.5 \pm 0.5 \pm 1.0 eV. No direct measurement of this quantity is listed in the PDG tables yet.

Speaker: Mr Andrey Sukharev (Budker INP)

43 Study of the process e+e- --> K+K-\pi+\pi- with the CMD-3 detector at VEPP-2000

Speaker: Dr Gennady Fedotovich

44 The Measurement of the P BarP cross section with CMD-3 Detector at VEPP-2000

The preliminary results of the e+e->P bapP cross section with CMD-3 detector at electron-positron collider VEPP-2000 in the c.m. energy range 1.92 - 2.0 GeV will be presented. Analysis based on 4.5 inversed picobarns of integrated luminosity, collected in first physical run of new facility. The events selection procedure based on the information from Drift Chamber and Calorimeters allowed clean sample of P barP events. The obtained results are in a good agreement with the previous measurements.

Speaker: Mr Aleksandr Popov (Budker Institute Of Nuclear Physics (BINP))

45 Weak radiative pion vertex in tau^- -> pi- l+l- nu tau decay

We carry out a detailed study of the branching fractions and lepton pair invariant-mass spectrum of \tau^- ->\pi^- \nu_\tau l^+l^- decays (l=e,\mu). In addition to the model-independent (QED) contributions, we include the structure-dependent (SD) terms, which encode information on the hadronization of QCD currents. The form factors describing the SD contributions are evaluated by supplementing Chiral Perturbation Theory with the inclusion of the lightest multiplet of spin-one resonances as active degrees of freedom. The Lagrangian couplings have been determined demanding the known QCD short-distance behaviour to the relevant Green functions and associated form factors in the limit where the number of colours goes to infinity. As a result, we predict BR(\tau^- ->\pi^-\nu_\tau e^+e^-)= (1.7^{+1.1}_{-0.3})x10^{-5} and BR(\tau^- -> \pi^-\nu_\tau \mu^+\mu^-) = [0.03,1.0]x10^{-5}. According to this, the first decay could be measured in the near future, which is not granted for the second one.

Speaker: Mr Pablo Roig Garces (IF (UNAM, Mexico))

19:00 Private visit to Sistine Chapel and Vatican Museum

Wednesday 11 September

Flavour Physics (I)

46 Charm physics with D and Ds at BESIII

Speaker: Dr Guang Zhao

Slides zhaog_phipsi13.pdf

47 Charm mixing and decays at B-Factories

Speaker: Gianluigi Cibinetto (FE)

Slides cibinetto-phipsi.pdf

48 Charm: mining, CP violation and rare decays at LHCb

Speaker: Dr Michael Alexander

Slides MAlexander-CharmMixingCPViolationAndRareDecays.pdf

49 Charm physics at HERA

Speaker: Massimo Corradi (BO)

Slides phipsi.pdf

10:20 Coffee break

Measurement and Theoretical Evaluation of g-2 (III)

50 HLS Approach to the muon g-2 evaluation

The HLS model supplemented with suitable SU(2)/SU(3) breaking schemes allows to build a phenomenological model which encompasses six e+e- annihilation channels (pi+ pi-, K+ K-, K0 K0bar, pi0 gamma, eta gamma, pi+ pi-pi0), the dipion spectrum in the tau decay and a few more meson annihilation partial width information. One thus yields a simultaneous description of all these physics channels by means of quite successful global fits of all the corresponding data. The fit results provide the six corresponding annihilation cross sections up to 1.05 GeV. This is used to determine accurately the leading order hadronic vacuum polarisation contribution up to the phi region. Supplementing this with additional information covering the physics channels falling outside the scope our model, one derives an improved estimate of the muon g-2. The data samples recently collected by KLOE play an important role in this improvement

Speaker: Mr Maurice Benayoun (LPNHE des Universites Paris 6 et 7)

Slides Roma_2013_v_F.pptx

51 Towards analytic four-loop corrections to the anomalous magnetic moment of leptons

The anomalous magnetic moments of the electron and muon have been measured to high accuracy. On the theory-side they are predicted including quantum corrections up to five loops. Whereas three-loop corrections are known analytically the four- and five-loop terms are only available in numerical form. In this talk first analytic four-loop results are presented. As a byproduct the fermionic contribution to the four-loop relation between the MSbar and on-shell quark mass in QCD is obtained.

Speaker: Prof. Matthias Steinhauser (KIT)

Slides steinhauser.pdf

52 Hadronic vacuum polarization contribution to g-2 from the lattice

In this talk, I will discuss the status of lattice computations of the leading hadronic contribution to the muon anomalous magnetic moment. The focus will be on methods that can help making the lattice determination competitive with the value obtained from the e+e- cross section.

Speaker: Prof. Maarten Golterman (San Francisco State University)

Slides golterman.pdf

53 The electroweak contributions to (g-2)_mu aafter the Higgs boson mass measurement

Speaker: Prof. Dominik Stöckinger (TU Dresden)

Slides PhiPsiSeptember2013.pdf

Flavour Physics (II)

54 Recent results on BR(K-> pi pi pi) at KLOE/KLOE-2

Speaker: Patrizia De Simone (LNF)

Slides PHIPSI2013_desimone.pdf

55 Study of the rare decay K+- --> pi+- gamma gamma and high precision measurement of the form factors of the semileptonic decays K+- to pi0 l+- nu

A sample of about 300 K+- to pi+- gamma gamma rare decays with a background contamination below 10% has been collected by the NA48/2 and NA62 experiments at CERN during low intensity runs with minimum bias trigger configuration. The presented measurements of the decay spectrum and rate provide a crucial test of the Chiral Perturbation Theory (ChPT) describing weak low energy processes. Semileptonic kaon decays offer the most precise determination of the CKM matrix element |Vus|. The experimental precision is however limited by the knowledge of the form factors of this decay, since these enter both the phase space integral and the detector acceptances. The NA48/2 experiment presents new measurements of the form factors of the semileptonic decays of charged kaons, based on 4.3 million Ke3 and 3.5 million Kmu3 decays, both with negligible background. The result matches the precision of the current world average on the vector and scalar form factors and allows to significantly reduce the form factor uncertainty on |Vus|. In addition, the comparison of both channels sets tight constraints on lepton flavor violation and other possible new physics.

Speaker: Mauro Raggi (LNF)

Slides raggi_phipsi.pdf raggi_phipsi.pptx

56 Searches for rare and forbidden kaon decays at the NA62 experiment at CERN

The decay K+ -> pi+ nu nu-bar is highly suppressed in the Standard Model (SM), while its rate can be predicted with minimal theoretical uncertainty. The branching ratio for this decay is thus a sensitive probe of the flavor sector of the SM.; however, the smallness of this BR (8 x 10^-11) and challenging experimental signature make it very difficult to measure. The primary goal of the NA62 experiment at the CERN SPS is to measure BR(K+ -> pi+ nu nu-bar) with ~10% precision. This will require the observation of 10^13 K+ decays in the experiment's fiducial volume, as well as the use of high-performance systems for precision tracking, particle identification, and photon vetoing. These aspects of the experiment will also allow NA62 to carry out a rich program of searches for lepton flavor and/or number violating K^+ decays. Such searches can probe new physics scenarios involving, for example, heavy Majorana neutrinos or R-parity violating SUSY. Part of the experimental apparatus was commissioned during a technical run in 2012; installation continues and data taking is expected to begin in late 2014. The physics prospects and the status of the NA62 experiment will be reviewed.

Speaker: Paolo Massarotti (NA)

Slides NA62_PHIPSI_Massarotti.pdf

13:10 Lunch

Baryon Form Factors

57 Theoretical and experimental review

Speaker: Simone Pacetti (PG)

Slides pacetti-phipsi13-pub.pdf

58 Results and perspectives on Baryon Form Factors from SND and CMD3

Speaker: Dr Sergey Serednyakov (Institute of Nuclear Physics, Novosibirsk)

Slides Serednyakov_SeredFFs.pdf

59 BaBar results on Baryon form factors

Speaker: Dr Vladimir Druzhinin (BINP, Novosibirsk, Russia)

Slides druzhinin_phipsi2013.pdf

60 Baryon Form factors at BESIII

Speaker: Yadi Wang (L)

Slides WangYadi.pdf

61 Baryon form factors program at JLAB

Speaker: Dr Bogdan Wojtsekhowski

Slides Wojtsekhowski_BaryonFFs_JLab.pdf

15:55 Coffee break

Heavy Meson Spectroscopy

62 Charmonium-like spectroscopy and decays from BESIII

Speaker: Dr Liang Yan

Slides 111.pdf

63 Parameters of Charmonium states from KEDR

Speaker: Dr Evgenii Baldin (Budker Institute of Nuclear Physics)

Slides Parameters of Charmonium states from KEDR

64 Exotic spectroscopy at B_Factories

Speaker: Prof. Alexander Bondar (Budker Institute Nuclear Physics)

Slides 3-A.Bondar_PhiPsi2013-new.pptx

65 Heavy quarks spectroscopy at LHCb

Speaker: Dr Simon Eidelman (Budker Institute of Nuclear Physics)

Slides 4-Eidelman_lhcb.pdf

66 Theoretical status of exotic spectroscopy

Speaker: Dr Thomas Mehen

Slides 5-Mehen.pdf

67 Doubly heavy exotics

Recent discoveries by Belle and BESIII of charged exotic quarkonium-like resonances provide fresh impetus for study of heavy exotic hadrons. In the limit N_c --> infinity, M_Q --> infinity, the (Qbar Q qbar q') tetraquarks (TQ-s) are expected to be narrow and slightly below or above the (Qbar q') and (Q qbar) two-meson threshold. The isoscalar TQ-s manifest themselves by decay to (Qbar Q) pi pi, and the ~30 MeV heavier charged isotriplet TQ-s by decays into (Qbar Q) pi. The new data strongly suggest that the real world with N_c=3, Q=c,b and q,q' = u,d is qualitatively described by the above limit. We discuss the relevant theoretical estimates and suggest new signatures for TQ-s in light of the recent discoveries. We also consider "baryon-like" states (Q Q' qbar qbar'), which if found will be direct evidence not just for near-threshold binding of two heavy mesons, but for genuine tetraquarks with novel color networks. We stress the importance of experimental search for doubly-heavy baryons in this context.

Speaker: Prof. Marek Karliner

Slides 6-karliner_doubly_heavy_exotics_PHIPSI13.pdf

20:30 Social dinner

Thursday 12 September

Symmetries (II)

68 Overview of CPT, T and Lorentz invariance tests at e+e- colliders

Speaker: Antonio Di Domenico (ROMA1;LNF)

Slides didomenico_phipsi2013_9.pdf

69 Search for CPT and Lorentz invariance violation in neutral kaons at KLOE/KLOE-2

Speaker: Mr Eryk Czerwinski (Jagiellonian University, Research Centre Juelich)

Slides phipsi2013_czerwinski.pdf

70 Status and prospects of the muonium experiment at J-Parc

Speaker: Dr Hiroyuki Torii

Slides Torii-MuHFS-PHIPSI13-confz.pdf

71 Measurement of the ratio of charged kaon leptonic decay rates at NA62

A lepton universality test by measurement of the helicity suppressed ratio RK of leptonic decay rates of the charged kaon has been performed by the NA62 experiment. A precision measurement of the ratio RK of the rates of kaon leptonic decays K+- to e+- nu and K+- to mu+- nu with the full minimum bias data sample collected with low intensity 75 GeV/c beam by the NA62 experiment at CERN in 2007-2008 is reported. The result, obtained by analyzing ~150,000 reconstructed K+- to e+- nu candidates with 11% background contamination, has a record precision of 0.4% and is in agreement with the Standard Model expectation. The record accuracy of 0.4% constrains the parameter space of new physics models with extended Higgs sector, a fourth generation of quarks and leptons or sterile neutrinos.

Speaker: Venelin Kozhuharov (LNF)

Slides Venelin-PhiPsi.pdf

72 New results in rare allowed muon and pion decays

Thanks to the simple underlying dynamics of pion and muon decays, small numbers of the available decay channels, and extremely well controlled radiative and loop corrections, these decays offer a uniquely sensitive means to explore details and limits of the underlying symmetries. For example the anomalously suppressed decay of the charged pion to the electron, $\pi^+ \to e^+\nu$ (labeled $\pi_{e2}$), provided an early signal of the V-A Lorentz structure of the weak interaction. Today, the $\pi_{e2}$ decay still offers the most sensitive test of lepton universality: the equality of the lepton couplings to the weak boson regardless of the lepton family (generation). Hence, $\pi_{e2}$ decay is highly sensitive to non-(V-A) terms manifested through pseudoscalar contributions. Radiative decays of the muon, $\mu^+ \to e^+ \nu \bar{\nu} \gamma$, and pion, $\pi^+ \to e^+\nu\gamma$, or $\pi_{e2\gamma}$, are sensitive in different ways to departures from the basic V-A dynamics of the weak interaction. Currently the experimental precision of all these processes lags significantly, i.e., by an order of magnitude or more, behind the precision of their theoretical description. We report on new, unpublished results on the radiative decay of the muon (RMD) from a comprehensive program of precise measurements of the pion and muon rare decays at the Paul Scherrer Institute, Switzerland, the PIBETA and PEN experiments. Compared to previous experiments, our recently completed data analysis improves the uncertainty of the RMD branching ratio by a factor of almost 30, and that of the extracted value for the Michel parameter $\bar{\eta}$ by a factor of 4. Both are in good agreement with the SM expectations. We also update the current status of the data analyses of $\pi_{e2}$ (implications on limits of lepton universality, as well as non-$V-A$ extensions to the SM) and $\pi_{e2\gamma}$ decays (pion form factors, additions to $V-A$ interaction terms). This work is highly complementary to the Frascati kaon decay measurement program, with both providing key new information.

Speaker: Dinko Pocanic (University of Virginia)

Slides pocanic_slides.pdf

10:40 Coffee break

Tau-lepton Physics

73 Precision measurement of the tau mass at BESIII

Speaker: Dr Xiaohu Mo

Slides moxh2013.pdf

74 Recent tau results from BELLE

Speaker: Dr Simon Eidelman (Budker Institute of Nuclear Physics)

Slides Eidelman.pdf

75 Recent tau results from BaBar

Speaker: Dr Alberto Lusiani (PI)

Slides lusiani-phipsi13-babar.pdf

76 Lattice Input on the V_us from inclusive hadronic tau decay data

The determination of V_us via finite energy sum rule analyses of flavor-breaking combinations of non-strange and strange hadronic tau decay data yields values of V_us ~3 sigma below both expectations based on 3-family unitarity and results obtained from analyses of Gamma[K_{ell 3}] and Gamma[K_{mu 2}]/Gamma[pi_{mu 2}]. A key issue in understanding whether this low value represents new physics or just an underestimate of the uncertainties in the existing analyses is the very slow convergence of the leading D=2 contribution to the OPE representation of the relevant flavor-breaking correlator difference. A sign of this slow convergence is the fact that switching from the "local scale" CIPT prescription to the "fixed scale" FOPT prescription for the relevant D=2 contour integrals leads to results for V_us differing by an amount ~0.0020 much larger than most total theory error estimates existing in the literature. Here we investigate the issue of which (if either) of the two prescriptions for the D=2 series is more reliable by studying lattice data for the relevant correlator differences, obtained using RBC/UKQCD n_f=2+1 domain wall fermion ensembles covering a range of light quark masses and lattice spacings. We then use the lessons learned from this comparison to improve and update two flavor-breaking sum rule determination of V_us.

Speaker: Dr Kim Maltman (York University)

Slides phipsi_13_vus_talk.pdf

77 Alpha_s from tau decays: perturbative expansion of spectral function moments

We will discuss recent developments in the QCD description of hadronic tau decays with emphasis in the perturbative contribution. Various moments of the hadronic spectral functions have been employed in the determination of the strong coupling alpha_s from tau decays. We will analyse the behaviour of their perturbative series under different assumptions for the large-order corrections and for the renormalization group improvement of the series. Some moments commonly employed in alpha_s analyses from tau decays should be avoided because of their perturbative instability. Finally, we will argue that some of the recent analyses do not employ an optimal strategy for an alpha_s determination.

Speaker: Mr Diogo Boito (Technische Universität München)

Slides BoitoPhiToPsi2013Talk.pdf

78 Low-energy constants and condensates from the V-A spectrum.

We present an analysis of the isospin-one V-A correlator based on our successful description of the OPAL V and A non-strange spectral data. We discuss the values obtained for the ChPT low-energy constants L_10 and C_87 as well as the dimension-six and eight condensates and compare them with those in the existing literature.

Speaker: Prof. Santiago Peris (Univ. Autonoma de Barcelona)

Slides Rome-2013.pdf

13:10 Lunch

Light Meson Spectroscopy

79 Light meson spectroscopy at KLOE/KLOE-2

Speaker: Matteo Mascolo (ROMA2)

Slides PhiPsi_2013_Mascolo.pdf

80 Light meson spectroscopy and gamma-gamma physics at BESIII

Speaker: Ms Xinying Song (Institute of High Energy Physics, Chinese Academy of Science)

Slides light_hadron_songxy.pdf

81 Light meson studies with WASA-AT-COSY

Detailed experimental studies of the decays and interactions of light mesons, such as pi0, eta and omega, are highly needed as precision tests for theoretical models. Such studies allow for extractions of parameters describing decay dynamics as well as transition form factors. Experimental results in this area can also provide measurements of symmetry breaking processes, test the symmetries of the Standard Model and contribute to the search for physics beyond the Standard Model. The WASA detector is one of the available experimental set-ups optimised for studying production and decays of light mesons. In contrast to the focus of this workshop, the mesons are produced through proton-proton or proton-deuteron collisions using a xed target in the WASA experiment. This talk will highlight the contributions made and ongoing studies by the WASA-at- COSY collaboration in the eld of light meson interactions.

Speaker: Dr Lena Heijkenskjold

Slides PhiPsi13_WASAlightmeson_Heijkenskjold.pdf

82 Meson photoproduction from the nucleon at CLAS

An extensive measurement programme of meson photoproduction from the nucleon has been obtained exploiting the CLAS detector in Hall-B of Jefferson Lab. The main aim of the programme is to provide high quality experimental data to constrain partial-wave analyses and reaction models used to determine the spectrum and properties of nucleon resonances. Obtaining accurate and detailed information on this spectrum would provide valuable insights regarding the dynamics and interactions of the nucleon's constituents. Theoretical predictions of the resonance spectrum can be obtained from a range of approaches including constituent quark models and more recently from Lattice QCD. Despite these exciting advances in theory the properties and even existence of many nucleon resonances are poorly established experimentally. The programme of measurements at CLAS will provide new, quality data on single and multiple meson photoproduction from the nucleon to better constrain the extraction of the spectrum. The experiments utilised linearly and circularly polarised photon beams on longitudinally and transversely polarised nucleon targets. The centre-of-mass energy, W, of the data set is 1.2 - 2.25 GeV, covering a large fraction of the resonance region. The FROzen Spin Target (FROST) and polarised H-D target used in the experiments will be discussed. Preliminary results for a range of single- and double- polarisation observables in meson photoproduction will also be presented.

Speaker: Dr Dan Watts

Slides WattsPhi2Psi13.pptx

83 To learn light scalars from semileptonic decays of heavy quarkonia

Thee mechanisms of light scalar meson production in the D_s+\to s\bar s e+\nu\to [\sigma(600)+f0(980)] e+\nu\to\pi+\pi-e+\nu decays are compared with the mechanisms of light pseudoscalar meson production in the D_s+\to s\bar s e+\nu\to (\eta/\eta') e+\nu decays. It is shown that the s\bar s\to\sigma(600) transition is negligibly small in comparison with the s\bar s\to f_0(980) one. As for the s\bar s\to f_0(980) transition, its intensity makes near thirty percent from the intensity of the s\bar s\to\eta_s (\eta_s=s\bar s ) transition. The D_s+\to\pi+\pi- e+\nu decays support the previous conclusion about a dominant role of the four-quark components ud\bar u\bar d and sd\bar s\bar d in the \sigma(600) and f0(980) mesons, respectively. The program of the light scalar investigation in the semileptonic decays of the D+(D-), D0(\bar D0) and B+(B-), B0(\bar B0) mesons is discussed.

Speaker: Prof. Nikolay Achasov (Sobolev Institute of Mathematics)

Slides Achasov_D_s^+_Roma_2013.pdf

16:10 Coffee break

Light Meson Spectroscopy (cont'd)

84 The puzzle of eta(1405) and eta(1475)

We raise the issue on the nature of the eta(1405) and eta(1475). We will show that so far there is no strong evidence for their being individual states. In particular, there exists a so-called "triangle singularity" mechanism which will alter the lineshape and shift the mass of a state eta(1440) in its decays into KK-bar pi, eta pipi, and 3pi.

Speaker: Dr Qiang Zhao (Institute of High Energy Physics, Chinese Academy of Sciences and Department of Physics, University of Surrey)

Slides zhao-2013-09-phipsi.ppt

Machines and Detectors (II)

85 Overview prospects at BINP

Speaker: Dr Ivan Koop (BINP)

Slides Koop-Phi-Psi-13.pdf

86 Post BEPCII and the Supert Tau Charm Factory

Speaker: Prof. Zhengguo Zhao (University of Science and Technology of China (USTC))

Slides STCF-FromPhiToPsi-2013.pdf

87 INFN tau-charm factory

Speaker: Dr Alberto Lusiani (PI)

Slides lusiani-phipsi13-ctau.pdf

88 Status of SuperKEKb abd BELLE II

Speaker: Boris Shwartz (Budker Institute of Nuclear Physics)

Slides shwartz-belle2-slides.pdf

Closing

89 Proceedings

Slides phipsi13_proceedings.pdf