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19-23 April 2010 DIS 2010 / Florence Neutron Single Target Spin Asymmetries in SIDIS

19-23 April 2010 DIS 2010 / Florence Neutron Single Target Spin Asymmetries in SIDIS (at JLab HallA) E. Cisbani INFN Rome and Italian National Institute of Health on behalf of the 6 GeV Transversity collaboration http://hallaweb.jlab.org/experiment/transversity/. Outline.

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19-23 April 2010 DIS 2010 / Florence Neutron Single Target Spin Asymmetries in SIDIS

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  1. 19-23 April 2010 DIS 2010 / Florence Neutron Single Target Spin Asymmetries in SIDIS (at JLab HallA) E. Cisbani INFN Rome and Italian National Institute of Health on behalf of the 6 GeV Transversity collaboration http://hallaweb.jlab.org/experiment/transversity/ E. Cisbani: n SSA @ JLab/Hall A

  2. Outline • Single Spin Asymmetries in SIDIS on transversely polarized target • “Transversity” Experiment in HallA • Kinematic • Target • Detectors (HRS + BB) • Hadrons Production • JLab 12 GeV prospective • “SIDIS” Experiment with SBS • “Transversity” Experiment with SoLID Ongoing analysis thanks to the excellent work of several PhD Students: C. Dutta (Kentucky), J. Huang (MIT), A. Kalyan (Kentucky), J. Katich (W&M), X. Qian (Duke), Y. Wang (UIUC), Y. Zhang (Lanzhou U) E. Cisbani: n SSA @ JLab/Hall A

  3. From SIDIS to SSA to DFFF Pretzelosity E. Cisbani: n SSA @ JLab/Hall A

  4. Collins Moments on proton/deuteron COMPASS/deuteron proton Hepex-0802.2160 From Pappalardo / Transversity 2008 • Proton: • K- and p- with opposite sign, strong flavor dependence (but K errors significant)! • K+ and p+ consistent with u dominance • COMPASS compatible with HERMES • Deuteron: consistent with 0, expected asymmetry on neutron as large as on proton From DIS2009 Larger effects at larger x E. Cisbani: n SSA @ JLab/Hall A

  5. Sivers Moments on proton/deuteron HERMES on p NEW DATA FROM COMPASS/Proton SEE H. Fischer and A. Martin talks in this conference COMPASS/deuteron PLB673(2009)127 PRL103(2009)152002 • Proton: • K+ twice p+ conflict with u dominance expectation • K- and p- consistent with 0 • COMPASS proton not fully compatible to HERMES • Deuteron: consistent with 0, expected asymmetry on neutron as large as on proton E. Cisbani: n SSA @ JLab/Hall A

  6. JLab Accelerator Facility 6 GeV CEBAF (< 2013) Max Current: 200 mA Max Energy: 0.8 - 5.9 GeV Long. Polarization: 85% E. Cisbani: n SSA @ JLab/Hall A

  7. Transversity on neutron: Hall A experimental setup e+3He→e’+p(K)+X • Beam e-: • 5.9 GeV, 15 mA • Neutron Target: • High pressure polarized 3Hepol. 65%, 50 mg/cm2 x 40 cm • Luminosity: 1036/s/cm2 • Electron Arm (BigBite): • E’=0.72.2 GeV,J=30°, DW=64 msr • Hadron Arm (HRS Left): • Ph =2.35 GeV/c ± 5%,J=30°, DW=6 msr, p/K ID • Kinematic region: • Q2 ~ 2.2 GeV2,x ~ 0.130.45, z~ 0.5 • Measure Collins, Sivers and Pretzelosity E06-010 Data Taking:Nov/08 – Feb/09 E. Cisbani: n SSA @ JLab/Hall A

  8. 3He (n) Polarized Target • Polarized 3He ~ polarized neutron target • Use 3 COMET lasers (narrow line, high power) for optical pumping of Rb vapor • Fast spin exchange (via K) by 3He hyperfine interaction in oven; small part of N2 to quench soft photon depolarization of Rb • Polarized 3He diffuses to the target chamber • Transverse Horizontal (In-plane) and Vertical orientations • 20 minute spin flip • NMR and EPR polarimetries • Superior performances: • Steady 65% polarization @ 15 uA beam (world record) E. Cisbani: n SSA @ JLab/Hall A

  9. Electron Arm (BigBite) E. Cisbani: n SSA @ JLab/Hall A

  10. Hadron Arm: HRS-L 1.27 NIM A522 (2004) 294 E. Cisbani: n SSA @ JLab/Hall A

  11. Mx Measured Phase Space DIS: Q2>1, W>2.3, Mx>1.6, 0.3<z<0.7 E. Cisbani: n SSA @ JLab/Hall A

  12. Hadron Identification • Aerogel Cherenkov Counter • p rejection > 98% • Time of Flight • K/p separation at 4s • RICH proximity focusing detector • K/p separation at 3.8s Preliminary Ph = 2.33 – 2.47 GeV/c Strongest quality cuts E. Cisbani: n SSA @ JLab/Hall A data from APS2010 / Y. Wang

  13. Projected Stat. on p Asymmetries Work in progress Preliminary results expected to be released within summer/2010 ! (Extend measurement to x=0.4) E. Cisbani: n SSA @ JLab/Hall A

  14. JLab at 12 GeV and the SSA measurements prospective in Hall A E. Cisbani: n SSA @ JLab/Hall A

  15. add Hall D (and beam line) Upgrade magnets and power supplies CHL-2 CEBAF 12 GeV upgrade 6 GeV CEBAF (< 2013) Max Current: 200 mA Max Energy: 0.8 - 5.9 GeV Long. Polarization: 85% 12 GeV CEBAF (>2013) Max Current: 90 mA Max Energy Hall A,B,C: 10.9 GeV Max Energy Hall D: 12 GeV Long. Polarization: 75-85% E. Cisbani: n SSA @ JLab/Hall A

  16. 1037 Peculiarity of JLab Phase Space Access unexplored valence region (high Q2 requires high luminosity) Hall A is already running at 1036 and will likely reach few 1037 (in polarized experiments) E. Cisbani: n SSA @ JLab/Hall A from TMD-Duke / M. Contalbrigo

  17. SSA on n in the 11 GeV era in Hall A • SIDIS on p and K (conditionally approved, 01/2009) – short term • G. Cates, E. Cisbani, G.B. Franklin, B. Wojtsekhowski • Similar layout of the 6GeV experiment at higher luminosity and acceptance • HRS replaced by a new large acceptance spectrometer (SBS), improved target • 2D binning on the relevant variables: x, P and z, for both hadrons and Q2 dependence • High x valence region (with overlap to HERMES, COMPASS, JLab6 data) • Proposal: http://hallaweb.jlab.org/collab/PAC/PAC34/PR-09-018-sidis.pdf • SoLID-Transversity experiment (approved, 01/2010) – medium term • J.-P. Chen, H. Gao, X. Jiang, J.-C. Peng, and X. Qian • Use solenoid magnet • 2p angular coverage  optimal systematics control • Precision measurement in 4D phase space (x, z, P and Q2) • Extended phase space coverage • Proposal: http://hallaweb.jlab.org/collab/PAC/PAC35/PR-10-006-SoLID-Transversity.pdf E. Cisbani: n SSA @ JLab/Hall A

  18. HERMES RICH SIDIS: Experimental Setup e+3He→e’+p(K)+X Measure the SSA of SIDIS processes n(e,e’p)X and n(e,e’K)X BB: e-arm at 30o  = 45 msr GEM Tracker Gas Cherenkov Shower  GMn/PR-09-019 SBS: h-arm at 14o  = 50 msr GEM tracker excellent PID / RICH Hadron CALO Most of the equipments from EM Form-Factors experiments Event rate: ~104×HERMES 60 days of production expected stat. accuracy: 1/10 of proton HERMES Beam: 50 A, E=8.8 and 11 GeV (80% long. Pol.) Target: 65% polarized 3He  GEn(2)/PR-09-016  Luminosity: 1.4×1037 cm-2s-1, 0.05 sr PAC34 Conditionally Approved experiment E. Cisbani: n SSA @ JLab/Hall A

  19. SIDIS: A new target E. Cisbani: n SSA @ JLab/Hall A from SBS-IV / G.D. Cates

  20. SIDIS: Hadron PID HERMES RICH 5.5 GeV K+ C4F10 gas REAL DATA from NIMA 479 (2002) 511 14.6 GeV e- 1.5 GeV p- Very stable performance (dn/(naerogel-1)= 1%, 9 years) Stored at UVa under safe/controlled conditions (also additional wall of spare Aerogel) E. Cisbani: n SSA @ JLab/Hall A

  21. Prop. Exp. Ebeam = 11.0 GeV Prop. Exp. Ebeam = 8.8 GeV Current Transversity Exp. E06-010 SIDIS: Q2 coverage We will investigate the Q2 dependence of the Sivers and Collins functions, with overlap in the region of HERMES; reveal higher twist effects. Analysis of the Q2 effect will use also the results of 6 GeV E06-010 Transversity experiment E. Cisbani: n SSA @ JLab/Hall A

  22. Azimuthal Coverage fh Partial coverage of fh but in sin/cos sensible regions 0.15 < x <0.65 Jh_cent. = 14° Ebeam = 11 GeV 4 target spin directions Complete coverage of the Collins, Sivers and “Pretzelosity” azimuthal angles with 4 target spin directions (with 8 target spin directions even better uniformity) E. Cisbani: n SSA @ JLab/Hall A

  23. SIDIS: Expected Statistical Accuracy on K • Superior quality of Kaon data • Extend at higher x with partial overlap with existing data on proton, deuteron and expected results of HallA Transversity 6 GeV DF from CTEQ5M FF from DSS Rate normalized to HERMES/p+d K production E. Cisbani: n SSA @ JLab/Hall A

  24. SoLID: experimental setup Solenoid magnetic field (2p azimuthal coverage) Polarized target in a fringe field similar to 6 GeV experiment Tracking: GEM technology CALO + Cherenkov threshold for PID Multi-RPC for timing Large part of the setup used for PVDIS experiment E10-006 PAC35 Approved experiment E. Cisbani: n SSA @ JLab/Hall A from JLab-PAC35 / X. Qian

  25. SoLID: Phase Space E. Cisbani: n SSA @ JLab/Hall A from JLab-PAC35 / X. Qian

  26. x SoLID: Projected Data E. Cisbani: n SSA @ JLab/Hall A from JLab-PAC35 / X. Qian

  27. Summary • 6 GeV “Transversity” Experiment on p and K • Data taken on n in 3 months (Nov/08 – Feb/09) • Almost completed analysis for p-SSA • First results to be released soon (likely before Summer/2010) • 12 GeV Prospective (after 2013) • Two SSA experiments proposed on 3He target in HallA • Will provide data on Transversity/Sivers/Pretzelosity in the valence region at different Q2 using the same physics mechanism but complementary instrumental approaches  different time scale and projected performance: • SBS-SIDIS: p and K SSA with quite improved statistics • SoLID-Transversity: p SSA with ultimate precision • both will benefit of JLab luminosity and 3He polarized targets progress E. Cisbani: n SSA @ JLab/Hall A

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