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19-23 April 2010 - Frascati Probing Strangeness in Hard Processes

19-23 April 2010 - Frascati Probing Strangeness in Hard Processes Kaon SIDIS experiments in Hall A at Jefferson Lab E. Cisbani INFN Rome and Italian National Institute of Health. Transverse Neutron Target and K Single Spin Asymmetries at 6 and 12 GeV (E06-010 and PR12-09-018).

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19-23 April 2010 - Frascati Probing Strangeness in Hard Processes

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  1. 19-23 April 2010 - Frascati Probing Strangeness in Hard Processes Kaon SIDIS experiments in Hall A at Jefferson Lab E. Cisbani INFN Rome and Italian National Institute of Health • Transverse Neutron Target • and K Single Spin Asymmetries • at 6 and 12 GeV • (E06-010 and PR12-09-018) E. Cisbani: kTMD @ JLab/Hall A

  2. SIDIS and TMD and Asymmetries PDF/TMD and FF Transversity PDF Sivers and Pretzelosity TMD ( Collins and unpolarized FF) E. Cisbani: kTMD @ JLab/Hall A

  3. 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 • Weak Q2 dependence From DIS2010 Larger effects at larger x E. Cisbani: kTMD @ JLab/Hall A

  4. Sivers Moments on proton/deuteron HERMES on p COMPASS/proton DIS2010 • Proton: • K+ twice p+ conflict with u dominance expectation • K- and p- consistent with 0 • COMPASS proton not fully compatible to HERMES -> possible W dependence ? • Deuteron: consistent with 0, expected asymmetry on neutron as large as on proton PRL103(2009)152002 New data welcome! E. Cisbani: kTMD @ JLab/Hall A

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

  6. Hall A today BigBite 2 High Resolution Spectrometers 3He polarized target E. Cisbani: kTMD @ 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 Experiment: E06-010 Data Taking:Nov/08 – Feb/09 E. Cisbani: kTMD @ 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: kTMD @ JLab/Hall A

  9. Mx 3He Asymmetries on p Preliminary E06-010 DIS: Q2>1, W>2.3, Mx>1.6, 0.3<z<0.7 E. Cisbani: kTMD @ JLab/Hall A

  10. 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: kTMD @ JLab/Hall A data from APS2010 / Y. Wang

  11. 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: kTMD @ JLab/Hall A

  12. Hall A in 2013 Gep5 configuration + Super BigBite • Large luminosity • Moderate acceptance • Forward angles • Reconfigurable detectors Form Factors at high Q2 and more E. Cisbani: kTMD @ JLab/Hall A

  13. Measure SIDIS processes n(e,e’p)X and n(e,e’K)X • Extract Sivers, Collins and Pretzelosity asymmetries on p and K with high statistics • Provide 2D binning (at least) on the relevant variables: x, P and z, for both hadrons • Provide Q2 dependence (possible signature of higher twists effect) • Explore for the first time the high x valence region (with overlap to HERMES, COMPASS, JLab6 data at lower x) • PR12-09-018: SIDIS on p and K (PAC34 - 01/2009) • Similar layout of the 6GeV experiment at higher luminosity and acceptance • HRS replaced by a new large acceptance spectrometer (SBS), improved target • Proposal: http://hallaweb.jlab.org/collab/PAC/PAC34/PR-09-018-sidis.pdf Conditionally approved E. Cisbani: kTMD @ JLab/Hall A

  14. HERMES RICH 12 GeV SIDIS: Experimental Setup e+3He→e’+p(K)+X BB: e-arm at 30o  = 45 msr GEM Tracker Gas Cherenkov Shower  GMn/E09-019 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/E09-016  Luminosity: 1.4×1037 cm-2s-1, 0.05 sr Synergies with other approved experiments E. Cisbani: kTMD @ JLab/Hall A

  15. A new 3He pol. target Current target New target • Convenction-driven gas flow insures mixing times of minutes or less • Metal target cell (gold coated) ensures the target can physically tolerate the beam • Keeping the target cell in vacuum ensures the detectors see a manageable overall luminosity E. Cisbani: kTMD @ JLab/Hall A

  16. 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- De Leo talk on Wed. Very stable performance (dn/(naerogel-1)= 1%, 9 years) Stored at UVa under safe/controlled conditions (also additional wall of spare Aerogel) E. Cisbani: kTMD @ JLab/Hall A

  17. Prop. Exp. Ebeam = 11.0 GeV Prop. Exp. Ebeam = 8.8 GeV Current Transversity Exp. E06-010 12 GeV SIDIS: Q2 coverage 2.4<W<4 GeV * 0.1<P<1.2 GeV 0.2<z<0.7 0.7<y<0.9 * 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: kTMD @ JLab/Hall A

  18. 12 GeV SIDIS: Expected 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: kTMD @ JLab/Hall A

  19. Summary • 6 GeV “Transversity” Experiment on p and K (E06-010) • Data taken on n in 3 months (Nov/08 – Feb/09) • Almost completed analysis for p-SSA (preliminary K asymmetries already measured) • New results to be released soon • 12 GeV Kaon in SIDIS (PR12-09-018) • SBS-SIDIS: p and K SSA on 3He target with significantly improved statistics (conditionally approved) • will benefit of JLab luminosity, new 3He polarized target and new large acceptance spectrometer (SBS) E. Cisbani: kTMD @ JLab/Hall A

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