H.Avakian, HEDT July 1 1 The Impact of Hermes on Other Experiments Harut Avakian (JLab) Hamburg, July 1 H.Avakian, HEDT July 1 2 Outline HERMES and the transverse structure of the nucleon 3D PDFs First measurements and interpretations Future measurements of SIDIS and DY DY at RHIC, JPARC,GSI SIDIS at JLAB12 and EIC GPDs with CLAS12 Summary H.Avakian, HEDT July 1 3 PDFs f p u (x), Form Factors F 1p u (t),F 2p u (t ).. TMD PDFs f p u (x,k T ), d2kTd2kT dx (FT) GPDs/IPDs W p u (x,r T ), d2rd2r W p u (k,r T ) Mother Wigner distributions d2rd2r d2kTd2kT Measure momentum transfer to quark Direct info about momentum distributions No information about spatial location of partons Probability to find a quark u in a nucleon P with a certain polarization in a position r and momentum k Structure of the Nucleon Measure momentum transfer to target Direct info about spatial distributions No direct information about underlying dynamics H.Avakian, HEDT July 1 4 SIDIS kinematical plane and observables Trento Conventions Beam polarization Target polarization U unpolarized L long.polarized T trans.polarized sin moment of the cross section for unpolarized beam and transverse target Phys.Rev. D70, (2004). H.Avakian, HEDT July 1 5 Off diagonal PDFs related to interference between states with different orbital momentum Transverse momentum of quarks k T required to describe azimuthal distributions of hadrons and in particular SSAs. k T - important for cross section description (also for exclusive production) Universality of k T -dependent distribution and fragmentation functions. Sign flip for f 1T , h 1 from DY to SIDIS predicted. (Collins,Metz 2003) Mulders & Tangerman (1995, the TMD bible) Transversity Sivers Boer-Mulders Factorization proven for small k T. (Ji,Ma,Yuan 2005) Gauge invariant definition of k T -dependent PDFs (Belitsky,Ji,Yuan 2003) The role of final state interactions in SSA ( Brodsky et al,Collins 2002 ) Spin structure k T leads to 3D description with 8PDFs H.Avakian, HEDT July 1 6 Collins fragmentation: Longitudinally polarized target Study transversely polarized quarks in the longitudinally polarized proton Provides independent information on the Collins function. curves, QSM from Efremov et al Kotzinian-Mulders Asymmetry (1996) H.Avakian, HEDT July 1 7 HERMES effect # First measurement of significant SSA in electroproduction A UT ~ Collins Transverse with respect to * ** e Kotzinian et al (1999) HT (75%) H.Avakian, HEDT July 1 8 Hard Processes Partonic scattering amplitude Fragmentation amplitude Distribution amplitude proton SIDIS/DER lepton pion electron positron pion e e + to pions proton lepton antilepton Drell-Yan BNL JPARC FNAL H.Avakian, HEDT July 1 9 Future results from BELLE Belle detector KEKB Asymmetric collider 8GeV e GeV e+ H.Avakian, HEDT July 1 10 l l+l+ RHIC-II DY-studies BNL DY di-lepton production at RHIC-II as a function of rapidity y Projected errors (red) compared to STAR and PHENIX (125 pb -1 ) and theory predictions. Factor 3-4 from continuous transverse data taking, 3-5 more lumi from new vertex focusing magnets. - - y y STAR HERMES coverage H.Avakian, HEDT July GeV requires shorter experiment. E906 spect. is only 26m long (60m for E866) New coils for M1 magnet (4.8 m was 14.5 m) Publications Expt. Funded 2009 Magnet DesignExperiment And constructionConstruction Proposed Jan Experiment Runs x7 more data compared to E866 FNAL Main Injector 120 GeV Tevatron 800 GeV H.Avakian, HEDT July 1 12 Sivers function at H.Avakian, HEDT July 1 13 Studies of DY at JPARC Expected distributions from Drell-Yan 50 GeV - Jen-Chieh Peng et al H.Avakian, HEDT July 1 14 experiment: asymmetric collider: p = 15.0 GeV in HESR p = 3.5 GeV in CSR internal polarised target with p = 22 GeV 1 yr of data taking Experiments at FAIR "Facility of Antiproton and Ion Research" H.Avakian, HEDT July 1 15 CLAS12 Solenoid 5T CTOF SVT Central Detector DC R1, R2, R3 LTCC FTOF PCAL EC HTCC TORUS Forward Detector Forward carriage Track resolution: p (GeV/c) 0.003p p 2 (mr) < 1 (mr)< 3 Wide detector and physics acceptance (current/target fragmentation) High beam polarization 85% High target polarization 85% Lumi > cm -1 s -1 (NH 3,ND 3 HD?) H.Avakian, HEDT July 1 16 CLAS12: Kinematical coverage Large Q 2 accessible with CLAS12 are important for separation of HT contributions Q 2 >1GeV 2 W 2 >4 GeV 2 (10) y2GeV SIDIS kinematics eXeX H.Avakian, HEDT July 1 17 D.S.Hwang (JLab-07) Flavor Decomposition Use double spin asymmetries for different targets and final state particles to extract the helicity distributions for different flavors Sum over quark flavors Extraction of k T -dependent distributions q+ (f 1 +g 1 ) and q- (f 1 -g 1 ) will require unfolding of spin independent and spin dependent contributions Jakob, Mulders, Rodrigues, Nucl. Phys. A 1997 A.Bacchetta (JLab-07) H.Avakian, HEDT July 1 18 A LL -P T -dependence P T -dependence of double spin asymmetries provide access to difference in k T -distributions of quarks with spin orientations along and opposite to the proton spin. hep-ph/ 0 2 =0.25GeV 2 D 2 =0.2GeV 2 proton deuteron H.Avakian, HEDT July 1 19 SIDIS ( *p X): LL x-section subleading moment Azimuthal asymmetry most sensitive to the difference of widths in polarized and unpolarized distributions. data from proton and deutron provides a complete set required for the flavor dependence studies proton deuteron H.Avakian, HEDT July 1 20 Collins fragmentation: Longitudinally polarized target UL ~ KM curves, QSM from Efremov et al Kotzinian-Mulders Asymmetry KM sin2 moment, sensitive to spin-orbit correlations: the only leading twist azimuthal moment for longitudinally polarized target More info will be available from SIDIS (COMPASS,EIC) and DY (RHIC,GSI) Transversely polarized quarks in the long. polarized nucleon H.Avakian, HEDT July 1 21 Collins Effect UT ~ Collins Study the Collins fragmentation for all 3 pions with a transversely polarized target and measure the transversity distribution function. H.Avakian, HEDT July 1 22 Collins Effect: from asymmetries to distributions Extraction of transverse spin distributions from CLAS12 assuming a simple model for Collins fragmentation for the favored case. need H.Avakian, HEDT July 1 23 Sivers effect UT ~ Sivers Requires: non-trivial phase from the FSI + interference between different helicity states Significant effect predicted in the target fragmentation region, in particular for baryons (target remnant also asymmetric) H.Avakian, HEDT July 1 24 polarization in the target fragmentation Semi-inclusive and exclusive Lambda production in the target fragmentation region provide access to underlying PDFs with CLAS12 p e 1 2 e Accessing polarized and strange PDFs with unpolarized target ! (no gluons) W.Melnitchouk and A.W.Thomas 96 J.Ellis, D.Kharzeev, A. Kotzinian 96 unique tool for polarization study due to self-analyzing parity violating decay H.Avakian, HEDT July 1 25 Higher Twist SSAs and Quark-Gluon Correlations Target sin SSA Beam sin SSA Discussed as main sources of SSA due to the Collins fragmentation In jet SIDIS only contributions ~ D 1 (Sivers type) survive With H 1 ( 0 )0 (or measured) Target and Beam SSA can be a valuable source of info on HT T-odd distribution functions Transversely polarized quarks ( et al ) H.Avakian, HEDT July 1 26 Non-perturbative TMD Perturbative region sin LU(UL) ~F LU(UL) ~ 1/Q (Twist-3) In the perturbative limit 1/P T behavior expected Asymmetries from k T -odd (g ,h 1 ) and k T -even (g 1 ) distribution functions are expected to have a very different behavior. 2.0 Beam SSA: 12 GeV H.Avakian, HEDT July 1 27 Hard Scattering Processes: Kinematics Coverage Study of high x B domain requires high luminosity 27 GeV compass hermes JLab ( upgraded ) Q2Q2 EIC collider experiments H1, ZEUS (EIC)