Physics of Elementary Particles and Atomic Nuclei
[ISSN 0367-2026] (Print), [ISSN 1814-7445] (Online)

Founded in 1970, the review journal Physics of Elementary Particles and Atomic Nuclei, brief name Particles & Nuclei, is published by the Joint Institute for Nuclear Research, Dubna. This is the most influential physical review journal in Russia.
Published by leading physicists from Member States of JINR, as well as scientists from all over the world, review articles in this eminent journal examine elementary particle physics, problems of vacuum in quantum field theory, condensed matter problems, symmetries in physics, string theories and gravity, nuclear physics, automatic processing of experimental data, accelerators and related instrumentation, accelerator-based transmutation studies, ecological implications of present nuclear and conventional energy sources, energy amplifiers based on accelerators.
The journal provides review articles in Russian and in English. Note: all volumes are translated into English and published by the Nauka/Interperiodika International Academic Publishing House. The translation journal appears under the name Physics of Particles and Nuclei.
Annualy 6 issues are published joined in one volume. In 2000-2004, the journal had a supplementary issue in addition to the six regular issues.
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Volume 45 (year 2014) , parts: 1
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THE 20TH INTERNATIONAL SYMPOSIUM ON SPIN PHYSICS (SPIN 2012)
Dubna, September 17-22, 2012
Proceedings of the Symposium
Editors: R.Lednick, A.V.Efremov, E.A.Kolganova
Session 1. SPIN STRUCTURE OF HADRONS
Akhunzyanov R.R., Shevchenko O.Yu. QCD Analysis of the Semi-Inclusive COMPASS and HERMES Data The first moments of polarized valence parton distribution functions truncated to the wide Bjorken x region 0.004 < x < 0.7 are directly (without any fitting procedure) extracted in the NLO QCD from combined semi-inclusive DIS data of COMPASS and HERMES Collaborations. Two scenarios for fragmentation functions are considered. Applying the proposed original procedure to these results we estimate the contributions of sea u and d quarks to the proton spin, which turn out to be simply zero within the errors.
Ermolaev B.I., Greco M., Troyan S.I. QCD Factorization for the DIS Structure Functions at Small x We suggest a new form of QCD factorization for inclusive processes at high energies and then reduce it to KT factorization. In turn, KT factorization can be reduced to collinear factorization when the unintegrated parton distributions have at least one maximum in k. This property of the parton distributions can be checked with studying data of experiment. The sharper the maximum is, the more accurate the transition to collinear factorization can be done. We apply our results to deduce theoretical restriction requirements on fits for parton distributions in both KT and collinear factorizations contrary to the present situation where the fits are introduced from purely phenomenological consideration so that any formula for them is acceptable if it matches experimental data.
Filip P. Can Mesons Have a Magnetic Moment? The response of pseudoscalar and vector mesons to strong magnetic fields is studied within a simple constituent quark model using analogy with bound states of positronium. Magnetic moments of charged vector mesons K*, D*, B* are predicted and it is found that mesons have magnetic polarizability. In extremely strong magnetic fields, behaviour of J/ mesons is discussed. We speculate on the existence of an induced magnetic moment of meson.
Ganbold G. Quark-Antiquark Bound States and QCD Running Coupling within Infrared Confinement Bound states of spin-half and spin-one particles are studied within a relativistic quantum-field model based on the infrared confinement. The spectra of quark-antiquark and two-gluon states are determined by master equations similar to the ladder Bethe-Salpeter equations. Masses of light, intermediate and heavy mesons are estimated in a wide range of scale (from hundreds of MeV up to 10 GeV). A new, independent and specific infrared-finite behavior of QCD effective coupling is revealed in the low-energy domain.
Giordano F. (HERMES Collab.) Flavor-Dependent Azimuthal Asymmetries in Unpolarized Semi-Inclusive DIS at HERMES The azimuthal cos h and cos 2h modulations of the distribution of hadrons produced in unpolarized semi-inclusive deep-inelastic scattering of electrons and positrons off hydrogen and deuterium targets have been measured in the HERMES experiment. For the first time, these modulations were determined in a 4-dimensional kinematic space for positively and negatively charged pions and kaons separately, as well as for unidentified hadrons. These azimuthal dependences are sensitive to the transverse motion and polarization of the quarks within the nucleon via, e.g., the Cahn, Boer-Mulders and Collins effects.
Goloskokov S.V. Polarized and Transversity GPDs in Kaon Leptoproduction We study the kaon leptoproduction on the basis of the handbag approach. We consider the leading-twist contribution together with the transversity twist-3 effects which were found to be important in the description of pseudoscalar meson production. We present our predictions for the cross section and spin asymmetries in the kaon leptoproduction.
Ivanov N.Ya. How to Measure the Charm Density in the Proton We study two experimental ways to measure the heavy-quark content of the proton: using the Callan-Gross ratio R(x,Q2) = FL/FT and/or the azimuthal cos (2) asymmetry in DIS. Our approach is based on the following observations. First, the ratio R(x,Q2) = FL/FT and azimuthal cos (2) asymmetry in heavy-quark leptoproduction are stable, both parametrically and perturbatively, within pQCD. Second, both these quantities are sensitive to resummation of the mass logarithms of the type s ln (Q2/m2). We conclude that the heavy-quark densities in the nucleon can, in principle, be determined from high-Q2 data on the Callan-Gross ratio and/or the azimuthal asymmetry. In particular, the charm content of the proton can be measured in future studies at the proposed Large Hadron-Electron (LHEC) and Electron-Ion (EIC) Colliders.
Korotkov V.A. (HERMES Collab.) Measurement of the Spin-Structure Function 2 and the Semi-Inclusive Double-Spin Asymmetries at HERMES A measurement of the virtual-photon asymmetry A2 and of the spin-structure function 2 of the proton are presented for the kinematic range of the HERMES experiment carried out at the HERA electron storage ring at DESY. Semi-inclusive longitudinal double-spin asymmetries provide new insight into the valence quark helicity distributions u and d.
Kotikov A.V., Shaikhatdenov B.G. Perturbative QCD Analysis of the Bjorken Sum Rule We study the polarized Bjorken sum rule at low momentum transfer squared Q2 3 GeV2 in the twist-two approximation and to the next-to-next-to-leading order accuracy.
Mekhfi M. Spin versus Helicity: Processes Involving Transversity We construct the spin formalism in order to deal naturally with processes involving transversity which are now of increasing popularity. The helicity formalism which is more appropriate for collision processes of definite helicity has been so far used to also manage processes with transversity, but at the price of computing numerous helicity amplitudes which generally involve unnecessary kinematical variables.
Sharma N., Martnez Torres A., Khemchandani K.P., Dahiya H. Magnetic Moments of the Low-Lying Negative-Parity Resonances We calculate the magnetic moments of the low-lying negative-parity J P = 1/2-, 3/2- resonances within the framework of chiral constituent quark model. The explicit contributions coming from the valence and sea quarks are being calculated.
Pappalardo L.L. Study of TMDs with polarized Beam and/or Targets A Fourier analysis of single- and double-spin azimuthal asymmetries measured at HERMES in semi-inclusive deep-inelastic scattering of unpolarized or longitudinally polarized leptons off tranversely polarized protons is presented for pions and charged kaons. The extracted amplitudes can be interpreted as convolutions of transverse momentum-dependent distribution and fragmentation functions. In particular, the measured double-spin asymmetries are sensitive to the poorly known worm-gear quark distribution 1T .
Selyugin O.V. The Structure of Nucleons and the Description of the Electromagnetic Form Factors The comparison of different sets of PDFs structure functions with the description of the whole sets of experimental data on electromagnetic form factors of the proton and neutron is made in the framework of our model [1] of t dependence of generalized parton distributions (GPDs) and some other models. It is shown that despite a small difference of the description of the inelastic processes by the different sets of PDF, there is an essentially large difference in the description of electromagnetic form factors of the nucleons.
Shevchenko O.Yu., Akhunzyanov R.R. QCD Analysis of DIS and SIDIS Data with Two Alternative Methods The global fit analysis of all published data on DIS and semi-inclusive DIS (SIDIS) asymmetries is performed in the next-to-leading (NLO) QCD order. The respective parameterization on polarized PDFs is constructed. The especial attention is paid to the impact of novel SIDIS data on the polarized distributions of light sea and strange quarks as well as on the polarized gluon distributions. The first moments of these distributions entering the nucleon spin occur surprisingly small quantities. The alternative direct (free of any fitting procedure) method of NLO QCD analysis is elaborated. Method is especially important for analysis of SIDIS data because it allows one to avoid the problems arising in the conventional fitting procedure: functional arbitrariness at initial scale and ambiguities in the error band calculation. Within the alternative method, the central values and uncertainties of the measured asymmetries directly propagate to the central values and uncertainties of the polarized PDFs we are interested in. The method is applied to all existing SIDIS data on pion production for an estimation in NLO QCD of the valence and sea quark contributions to the proton spin. As a result, one arrives at the conclusion that, contrary to the valence contributions, the sea contributions to the proton spin are compatible with zero within the errors.
Leader E., Sidorov A.V., Stamenov D.B. Importance of Fragmentation Functions in Determining Polarized Parton Densities New fragmentation functions (FFs) are extracted from a NLO QCD fit to the preliminary COMPASS data on pion and kaon multiplicities. It is shown that the new kaon FFs are very different from those of De Florian et al. (DSS) and Hirai et al. (HKNS). The sensitivity of the extracted polarized PDFs to the new FFs is discussed.
Soleymaninia M., Khorramian A.N., Moosavinejad S.M., Arbabifar F. QCD Analysis of Fragmentation Functions Considering Double-Spin Asymmetry of SIDIS Processes We extract new sets of pion and kaon fragmentation functions (FFs) at NLO applying combined analysis of single-inclusive electron-positron annihilation and semi-inclusive deep-inelastic lepton-nucleon scattering (SIDIS). We use zero-mass variable-flavor-number (ZM-VFN) scheme in our analysis.
Khandramai V.L., Solovtsova O.P., Teryaev O.V. QCD Analysis of the Bjorken Sum Rule Revisited We present extended analysis of the polarized Bjorken sum rule using the four-loop expression for the coefficient function CBj (s ) available now and the recent low-Q2 data from the Jefferson Lab and COMPASS experiments. We demonstrate that the perturbative series for the function CBj gives a hint to its asymptotic nature manifesting itself in the region Q2 1 GeV2. It is confirmed by the considered integral model for the perturbative QCD correction. We analyze values of higher twist terms extracted from the mentioned data and discuss the interplay between higher orders perturbative and higher twist contributions. We extend our consideration to the Gross-Llewellyn Smith sum rule and investigate the relation between higher twist coefficients in these two sum rules.
Strzik-Kotlorz D., Kotlorz A. DGLAP Evolution of the Truncated Moments of PDFs in Spin Physics We review evolution equations for truncated Mellin moments (TMM) of the parton densities. The main finding of the presented approach is that the nth truncated moment of the parton distribution obeys the DGLAP-like equation, with a rescaled splitting function P'(z) = znP(z). This approach allows one to restrict the analysis to the experimentally available Bjorken-x region. We present some applications of TMM to study the spin structure functions of the nucleon.
Taheri Monfared S., Khorramian Ali N., Haddadi Z., Najafgholi A. The Impact of Target Mass Correction on Polarized Parton Distribution Functions Considering the nonzero mass effect of the target in extracting polarized parton distribution functions (PPDFs) in preasymptotic region is not negligible. We extract PPDFs from available proton structure function data and study the numerical effects of target mass corrections (TMCs). PPDFs with and without this correction are compared.
Teryaev O.V. Can Gluon Spin Contribute to That of Nucleon? The transformation of angular momentum to its Belinfante form requires the smooth behaviour of classical fields at infinity which for the case of quantum operators transforms to the smooth behaviour of matrix elements at small momentum transfers. For the case of quarks, this provides the kinematical counterpart of UA(1) problem, while for gluons there is a contradiction between kinematics and dynamics governed by Kogut-Susskind pole. This may result in the violation of equivalence principle for nucleons or in the stringent constraints to the strange quark polarization in nucleons, while the most likely outcome would be the impossibility to separate gluon angular momentum to spin and orbital parts in the meaningful way.
Zhun Lu Chiral-Odd TMDs in Drell-Yan Processes We calculate the Boer-Mulders function of the pion by applying the MIT bag model, and compare the result with that from the spectator model. We then study the azimuthal asymmetries contributed by the chiral-odd transverse momentum distributions in pion-nucleon Drell-Yan process at COMPASS and in proton-proton Drell-Yan process at RHIC, J-PARC, E906, and NICA.
Session 2. SPIN IN HADRONIC REACTIONS
Abramov V.V. Polarization Phenomena in Hadronic Reactions Predictions are made in the framework of the effective color field (ECF) model for polarization observables in p + A X, A + A X, and p + Pb pX reactions. The predictions can be checked in the polarization experiments at IHEP (SPASCHARM), JINR (NICA) and BNL (RHIC). Estimates of quark masses and anomalous chromomagnetic quark moments are given.
Alekseev I. (EPECUR Collab.) High Precision Measurements of the Pion-Proton Elastic Scattering and Kaon-Lambda Production in the EPECUR Experiment Study of the pion-nucleon scattering can produce a rich information on the dynamics of the strong interaction and baryon spectroscopy. The EPECUR Collaboration is aimed at the research of baryon resonances in the second resonance region in s-channel via pion-proton elastic scattering and kaon-lambda production.
Corliss R. (STAR Collab.) Recent Star Results on W Production and Asymmetry in Polarized Collisions at = 500 GeV The production of W bosons in longitudinally polarized proton-proton collisions at RHIC is a unique way to study the flavor-dependent spin structure of the proton, since at leading order it couples directly and exclusively to specific quark flavor pairings: u + W+ and + d W-. Measurement of the longitudinal single-spin asymmetry of the electron decay daughters in W production is sensitive to the polarizations of the quarks involved. Results from the first proton-proton collisions at = 500 GeV in 2009 are presented, along with a discussion of the forward-rapidity tracking upgrade.
Jian Deng (STAR Collab.) Longitudinal Spin Transfer to and in Polarized Proton-Proton Collisions at = 200 GeV at STAR The longitudinal spin transfer DLL of and hyperons is expected to be sensitive to the helicity distribution function of strange (anti)quarks, and to the polarized fragmentation functions. We report new results on DLL, extracted from = 200 GeV polarized pp collisions recorded at the STAR detector during the 2009 RHIC run. These new results cover midrapidity || < 1.2, with extended pT up to 6 GeV/c.
Gal C. (PHENIX Collab.) Measurements of the Midrapidity Parity-Violating Spin Asymmetries for W Bosons at PHENIX The parity-violating W single-spin asymmetry, in longitudinally polarized p + p collisions, can give us a clean way to access the - and -polarized parton distribution functions. The current status of the analysis of the 2011 data set and future prospects will be presented.
Yuji Goto (PHENIX Collab.) Inclusive Cross Section and Single Transverse-Spin Asymmetry of Very Forward Neutron Production at PHENIX The cross section and xF dependence of AN of very forward neutron production in polarized p + p collisions at = 200 GeV were measured in the PHENIX experiment at RHIC. The measured cross sections were consistent with the xF scaling claimed by the ISR experiment. Significant negative AN was observed in the forward region, and no significant backward AN was observed. We also measured and pT dependence of AN of very forward neutron production at from 62.4 to 500 GeV.
Kanazawa K., Koike Y. TWIST-3 Quark-Gluon Correlation Contribution to Transverse Single-Spin Asymmetry for Direct-Photon and Single-Jet Productions in pp Collision We study the contribution of the collinear twist-3 quark-gluon correlation to the transverse single-spin asymmetry in direct-photon and single-jet productions in pp collision. At typical RHIC kinematics we find sizable asymmetries in the forward region of the polarized nucleon while they are almost zero in the backward region. We also find that the soft-fermion pole contribution is vanishingly small, suggesting the measurement of these asymmetries provides us with a unique opportunity to determine the net soft-gluon pole function.
Karyan G. (HERMES Collab.) Charged Hadron Multiplicities at the HERMES Experiment The HERMES Collaboration has measured charge-separated pion and kaon multiplicities in semi-inclusive deep inelastic scattering using a 27.6 GeV electron or positron beam scattering off a hydrogen or deuterium target. The results are presented as a function of the Bjorken variable xB, the negative squared four-momentum transfer Q2, the hadron fractional energy z and its transverse momentum Ph. These data will be very useful to understand the quark-fragmentation process in deep-inelastic hadron electroproduction and will serve as crucial input in the understanding of spin asymmetries in polarized semi-inclusive deep-inelastic scattering.
Koster J. Transverse Single-Spin Asymmetries in Polarized Proton-Proton Collisions at PHENIX The PHENIX experiment probes the transverse spin structure of the proton with asymmetries of particle production in polarized proton collisions. This talk summarizes the measurements of AN in hadron production at forward and at midrapidities.
Lajoie J. (PHENIX Collab.) Prompt Photon AN with the PHENIX MPC-EX Detector The PHENIX MPC-EX detector is a Si-W preshower extension to the existing Muon Piston Calorimeters (MPC). The combined detectors will make possible a measurement of the prompt photon single-spin asymmetry AN in 200 GeV transversely polarized p + p collisions, which will help elucidate the correlation of the transverse motion of valence partons in the proton with the proton spin.
Lee S.H. (PHENIX Collab.) Measurement of ALL and Cross Section of High-pT Charged Meson Production for Constraining G at PHENIX PHENIX at RHIC measured invariant differential cross section and double helicity asymmetry ALL of high-pT charged pion production in polarized p + p collision at = 200 GeV. Interpretations of preliminary results regarding constraining gluon helicity distribution are discussed.
Nogach L. (ANDY Collab.) Measurements of Forward Jet Production in Polarized pp Collisions at = 500 GeV The ANDY project at RHIC was proposed to measure the analyzing power for the Drell-Yan production. Test runs took place during polarized proton operations of RHIC in 2011 and 2012 with a model of the ANDY apparatus in place. In total, an integrated luminosity of 9 pb-1 with beam polarization of 50% was sampled. The primary detector components were a hadron calorimeter (HCal) that spanned the pseudorapidity interval 2.4 < < 4.0 and a small electromagnetic calorimeter (ECal). Basic goals for ANDY test running were to establish the impact of the third interaction region on RHIC performance and to demonstrate HCal calibration. Energy scale of HCal was established using neutral pion reconstruction and checked with hadronic response. In addition, data with a trigger based on HCal energy sum were taken to study jet events. First measurements of analyzing power in the forward jet production are reported.
Chetvertkov M.A., Chetvertkova V.A., Nurusheva M.B., Nurushev S.B., Ridiger A.V. Helicity Conservation Hypothesis and pp-Elastic Scattering TWe propose the helicity conservation model for description of polarization effects in the pp-elastic scattering at asymptotic energies. In this model the complete set of experiments will consist of only three observables. The predictions of model are compared with experimental data.
Oide H. (PHENIX Collab.) Measurement of Longitudinal Single-Spin Asymmetry of W at Forward/Backward Rapidities with PHENIX at = 500-510 GeV Polarized p + p Collisions The PHENIX experiment has collected about 25 pb-1 longitudinally polarized p + p collisions at = 500 GeV in 2011 run for probing antiquark polarization. In this talk the first preliminary result of AL is presented.
Pan Y. (STAR Collab.) Transverse Single-Spin Asymmetry Measurements at STAR Transverse single-spin asymmetries AN are expected to be sensitive to parton polarization and orbital angular momentum contributions to the nucleon spin. Significantly large AN has been observed in different collision systems such as semi-inclusive deep inelastic scattering (SIDIS) and polarized proton-proton (pp) collisions, indicating a dominant contribution of partonic interactions in the nonperturbative regime. Therefore it is critical to measure AN in various channels of polarized pp collisions in order to complement SIDIS data and to constrain theoretical models. We report STAR asymmetry measurements on midrapidity hadron-jet and dihadron correlations at = 200 GeV and forward rapidity inclusive hadron production at = 500 GeV polarized pp collisions.
Perry J. Approximation of Jet Axis in Rapidity Separated Dihadron Correlations The PHENIX experiment has observed particle production asymmetries in transversely polarized proton collisons. This talk presents a novel approach for separating the final-state and initial-state components of the observed asymmetries using the existing PHENIX detector.
D'Alesio U., Murgia F., Pisano C. Probing TMDs through Azimuthal Distributions of Pions Inside a Jet in Hadronic Collisions The azimuthal distributions around the jet axis of leading pions produced in the jet fragmentation process in pp collisions are studied within the framework of the so-called generalized parton model. The observable leading-twist azimuthal asymmetries are estimated in kinematic configurations presently investigated at RHIC. It is shown how the main contributions coming from the Collins and Sivers effects can be disentangled. In addition, a test of the process dependence of the Sivers function is provided.
Rossiyskaya N. (COMPASS Collab.) Study of Heavy Hyperons Production in DIS at COMPASS Samples of and hyperons produced in deep-inelastic muon scattering off 6LiD target were collected with the COMPASS experimental setup at CERN. The relative yields of -(1385), -(1385), +(1385), -(1321), and +(1321) hyperons decaying into the () were measured. The yield ratios of heavy hyperons to were found to be in the range 3.8-5.6% with a precision of about 10%. The experimental values are used to tune the parameters of the LEPTO Monte-Carlo generator relevant for strange particle production.
Shmakova V. (ANKE Collab.) Measurement of the Spin-Correlation Coefficients Ax,x and Ay,y in the Quasifree np {pp}s- Reaction near Threshold at ANKE-COSY A kinematically complete double-polarization measurement of the quasifree np {pp}s- reaction near threshold has been performed using the ANKE spectrometer at COSY-Jlich. Here {pp}s represents a two-proton system with an excitation energy less than 3 MeV. The transversely vector polarized deuteron beam and the internal polarized ANKE hydrogen target were used to determine the spin-correlation coefficients Ax,x and Ay,y. Events from the quasifree np d0 reaction were recorded simultaneously and used for both beam and target polarimetry. In addition, the product of the beam and target polarizations could be estimated from the Ay,y coefficient. The storage cell within the polarized target was the main source of background events. Dedicated runs, with no gas in the cell and with the cell filled with N2 gas, were taken to study the backgrounds. The data analysis procedure and the initial results of the experiment are presented.
Svirida D. (STAR Collab.) Improving Results on Transverse Double-Spin Asymmetries in the CNI Region at STAR Double-spin effects in polarized pp-elastic scattering in the Coulomb nuclear interference (CNI) region are sensitive to small contributions to the nuclear amplitude in addition to the Pomeron exchange dominating at high energies. Measurements of double-spin asymmetries require external luminosity normalization using collision counts for all spin combinations. Several possible sources of such data from various STAR subsystems were thoroughly analyzed to make the best choice. BBC arrays were found to be free of double-spin effects to the level of ~ 2 10-4 thus leading to the systematic uncertainty ~ 10-3 in the value of (ANN + ASS)/2.
Tsirkov D. (ANKE Collab.) Differential Cross Section and Vector Analyzing Power of the ppol p {pp}s0 Reaction at 353-700 MeV The reaction ppol p {pp}s0 was studied with the ANKE spectrometer at COSY-Jlich using a polarized beam with the energies of 353, 500, 550, and 700 MeV. The proton pairs {pp}s were detected at low excitation energy Epp < 3 MeV, where S wave dominates. The angular dependences of vector analyzing power Ay and differential cross section d/d of the reaction have been obtained for the most of the angular range at 353 MeV and forward angles at the higher beam energies. The partial wave amplitude analysis, done with the 353 MeV results, is important for Chiral Perturbation Theory (CPT) tests at this energy. The data at higher energies detalize the energy dependence of d/d (0) obtained earlier. It allows one to learn about the dynamics of the (1232) resonance excitation in the two-nucleon systems.
Session 3. SPIN PHYSICS WITH PHOTONS AND LEPTONS
Aghasyan M., Avakian H. Extracting TMDs from CLAS12 Data We present studies of double longitudinal spin asymmetries in semi-inclusive deep inelastic scattering using a new dedicated Monte Carlo generator, which includes quark intrinsic transverse momentum within the generalized parton model based on the fully differential cross section for the process. Additionally, we employ Bessel weighting to the MC events to extract transverse momentum-dependent parton distribution functions and also discuss possible uncertainties due to kinematic correlation effects.
Belostotski S.L. (HERMES Collab.) Spin Transfer to and Hyperons in Deep Inelastic Scattering at HERMES Preliminary results on the spin transfer to the and hyperons measured by the HERMES Collaboration are presented. Longitudinal spin transfer directed along the virtual-photon momentum in the rest frame is found to be DLL = 0.19 0.04(stat.) 0.02(syst.), the transverse component being compatible with zero. For , both longitudinal and transverse components are compatible with zero within statistical errors of 0.1.
Braun Ch. (COMPASS Collab.) COMPASS Results on Transverse Spin Asymmetries in Identified Two-Hadron Production in SIDIS COMPASS is a fixed target experiment at CERN where nucleon spin structure and hadron spectroscopy are investigated using a 160 GeV/c polarized + beam. An important part of its physics program are the measurements of single-spin asymmetries (SSA) in semi-inclusive deep inelastic scattering (SIDIS) on transversely polarized targets. Data on a deuteron target (6LiD) were taken in 2002-2004. After taking the first data on a transversely polarized proton target (NH3) in 2007, a full year of data taking followed in 2010 to increase precision. The SSA of identified hadron pairs consisting of charged pions and/or kaons from the 2010 data are shown for the first time and compared to model predictions and results from HERMES.
Kageya T. (CLAS Collab.) Measurements of Spin Observables in Pseudoscalar Meson Photoproduction Using Polarized Neutrons in Solid HD A measurement of pseudoscalar meson photoproduction from longitudinally polarized solid HD has been carried out with the CLAS at Thomas Jefferson National Accelerator Facility (Jlab) with circularly and linearly polarized photon beams. The aim is to measure a complete set of spin observables for the neutron simultaneously from the same experiment. As a polarized neutron, deuteron in HD was used. Preliminary asymmetries are shown for the - channel.
Makke N. (COMPASS Collab.) Study of the Hadronization Process from Single-Hadron and Hadron-Pair Production in SIDIS at COMPAS Recent results on single-hadron and hadron-pair multiplicities measurement in semi-inclusive deep inelastic muon scattering on nuclear target at the COMPASS experiment at CERN are presented and discussed.
Martin A. (COMPASS Collab.) COMPASS Results on Collins and Sivers Asymmetries for Charged Hadrons The study of transverse spin and transverse momentum effects is an important part of the scientific program of COMPASS - a fixed target experiment at the CERN SPS taking data since 2002. The studies are carried on by measuring the hadrons produced in deep inelastic scattering (DIS) of 160 GeV/c muons off different targets. Among the possible asymmetries in the hadron azimuthal distributions, particularly interesting are the Collins and Sivers asymmetries which the COMPASS Collaboration has measured using transversely polarized deuteron and proton targets. Here new results for charged pions and kaons obtained from the 2010 run with a transversely polarized proton target are presented for the first time.
Murray M. (HERMES Collab.) DVCS at HERMES This talk explores the impact that the HERMES experiment has had regarding knowledge of the Deeply Virtual Compton Scattering (DVCS) process. We discuss the various measurements that HERMES has contributed to the library of DVCS knowledge [1-3], with focus, in particular, on the recent high-precision beam spin and charge asymmetries [4].
Nefedov Yu. (BES-III Collab.) Recent Results of the BES-III Experiment The BES-III experiment in Beijing takes data in tau-charm domain since 2009. For the moment, the world largest samples of J, (3686), (3770), and (4040) data have been collected. The current status of the BES-III experiment is presented. The overview of recent results on light hadron, charmonium, and charm physics is given.

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Editor-in-Chief

V. G. Kadyshevskii

Assistents Editor-in-Chief:

V. L. Aksenov, V. A. Matveev, Nguen van Hieu

Editorial board:

A. B. Arbuzov,
V. A. Bednyakov,
V. V. Burov,
M. A. Vasiliev,
V. V. Volkov,
V. V. Voronov,
P. I. Zarubin,
G. M. Zinovjev,
A. P. Isaev (Secretary),
E. A. Krasavin,
O. N. Krokhin,
R. Lednicky,
E. V. Lychagin,
I. N. Meshkov,
D. Nagy,
Yu. Ts. Oganessian,
A. G. Popeko,
A. A. Starobinskii,
Ch. Stoyanov,
Gh. Stratan,
G. V. Trubnikov,
V. I. Yukalov

Head of the Editorial Office

G. V. Fedorova

Tel.: (49621) 6-26-50
e-mail: pepan@jinr.ru
FAX: +7(49621)6-58-92

Scientific Editor of the English translation

G. I. Smirnov

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