Analysis Update E06-010 Transversity

1. Analysis Update • E06-010Transversity Jin Huang • PhD Candidate, MIT • For Hall A Collaboration Meeting • June 10, 2010 @ JLab

2. E06-010 Overview • World first measurement of the SSA and DSA in SIDIS Reaction • PAC29 approved with A rating • Major installation • 3He Target, BigBite Electron Package, LHRS RICH • Successful data taking from Oct 08 to Feb 09 • Spokespersons Xiaodong Jiang (Rutgers/Los Alamos, Contact Person), Jian-ping Chen (JLab), Evaristo Cisbani (INFN-Rome), Haiyan Gao (Duke), Jen-Chieh Peng (UIUC) • 7 Thesis Students • K. Allada (Kentucky), C. Dutta (Kentucky), X. Qian (Duke) • J. Huang (MIT), J. Katich (W&M), Y. Wang (UIUC), Y. Zhang (Lanzhou U) Jin Huang <jinhuang@mit.edu>

3. Leading-Twist TMDs Nucleon Spin Quark Spin h1= Boer-Mulder f1 = h1L= Helicity g1 = h1T = Transversity f1T= g1T= h1T= Sivers Pretzelosity : Probed by E06-010 Jin Huang <jinhuang@mit.edu>

4. Access TMDs through SIDIS f1 = Unpolarized Boer-Mulder h1= Worm-Gear h1L= Transversity h1T = Polarized Target Sivers f1T= Pretzelosity h1T= Polarized Beam and Target g1 = g1T= Worm-Gear SL, ST: Target Polarization; le: Beam Polarization Jin Huang <jinhuang@mit.edu>

5. E06‑010 Experiment Setup Luminosity Monitor • Polarized 3He Target • Spin Flip & 3D rotation • 65% Polarization in experiment • Polarized Electron Beam • ~80% Polarization • Fast Flipping at 30Hz • BigBite at 30º as Electron Arm • Pe = 0.7 ~ 2.2 GeV/c • MWDC/Shower/Scintillator • HRSL at 16º as Hadron Arm • Ph = 2.35 GeV/c • VDC/S1&2/A1/Gas C/RICH/Lead Glass Beam Polarimetry (Møller + Compton) Jin Huang <jinhuang@mit.edu>

6. Analysis Progress • Detector Calibration Done • Reported in last collaboration meeting • Target analysis close to finalization • Extensive data quality checks • Two analysis teams cross check results • Red Team: Maximum Likelihood Method • Blue Team: Local Pair-Angular Bin-Fit Method • Asymmetry results are consistent • Systematics in progress • Active theory supports Jin Huang <jinhuang@mit.edu>

7. Target AnalysisY. Zhang, C. Dutta, etc. Preliminary Target Density • Polarimetry analyzed • NMR/water calibration • EPR • Target density close to finalized • Density measurement • Density w/ temperature correction • Temperature calibration coming soon • Final polarization table coming soon ~90% ~1.5% ~8% Jin Huang <jinhuang@mit.edu>

8. Simulation of the ExperimentX. Qian, etc. BigBite Momentum • GEANT3 Simulation of BigBite • COMGEANT based • Rate study • Confirmed electron arm contamination study Data MC (Sum All) Jin Huang <jinhuang@mit.edu>

9. Simulation of the ExperimentA. Puckett, X. Qian etc. • SIMC based simulation • Coming soon • Construct BigBite • Update HRS/Target • Simulating coinc event • pair contamination • diffractive ρ0 • cross section • bin centering • angular asymmetry extraction Energy Transfer normalization in progress MC Data Jin Huang <jinhuang@mit.edu>

10. Sign Checks • Target spin sign • Carefully checked/maintained/recorded • Beam helicity sign • Important yet tricky • Could be easily flipped during installation/software • No direct online check for 3He experiments • Off line checked with a consistent story • 21 elastic/quasi-elastic data sets checked Also by B. Zhao, G. Jin • Spin precession calculation • Cross check sign with parity DAQ (with R. Michaels) • Cross check welcome Jin Huang <jinhuang@mit.edu>

11. Data Quality Check and Cuts • Data Quality Check • Run selection/beam trip cut/yield check/witness channel check • Cuts/contamination and systematic effect checked plot by X. Qian Jin Huang <jinhuang@mit.edu>

12. x bin 1 2 3 4 Data Coverage x bin 4 : φh- φS x bin 1 : φh- φS Q2>1GeV2 W>2.3GeV x bin 1: φh+ φS x bin 4 : φh+ φS z=0.4~0.6 W’>1.6GeV Kinematics Coverage pT& ϕh± ϕS Coverage Jin Huang <jinhuang@mit.edu>

13. Asymmetry Extraction • It’s not simple! • Spin flip/angular coverage/kinematics dependence • Two analysis team • Independent method/code/compare results • Blue Team • local pair-angular bin-fit method • Low bias from yield drift • ideal for pion spin asymmetry extraction • Red Team • Maximum Likelihood method • Tech note: http://www.jlab.org/~jinhuang/Transversity/MLE.pdf • Stable at low statistic/capable of high dimensional fit Jin Huang <jinhuang@mit.edu>

14. Result Compare • Both asymmetry and modulation cross checked • Results are well consistent E06010 RAW Asym. Preliminary Jin Huang <jinhuang@mit.edu>

15. Preliminary AUT Results • 3He Collins SSAs are not large (as expected) • 3He Sivers SSAs follow the trend of Anselmino et al. 2009 E06010 Preliminary Jin Huang <jinhuang@mit.edu>

16. Preliminary AUT Results, 2D plot E06010 Preliminary >2σ signal! Jin Huang <jinhuang@mit.edu>

17. Preliminary ALT Results • Preliminary 3He ALT • Systematic uncertainty is still under work • Projected neutron ALT stat. uncertainty : 6~10% E06010 Preliminary Jin Huang <jinhuang@mit.edu>

18. Conclusion • First measurement of angular modulated SSA and DSA in neutron (3He) SIDIS • Data cover valence range • In progress: • Simulation (coinc channel) • Systematics • Neutron asymmetry extraction • Kaon ALT asymmetries • Submitting first paper in few months Jin Huang <jinhuang@mit.edu>

19. Backup Slides Systematics Table Jin Huang <jinhuang@mit.edu>

20. Systematics of ALT Jin Huang <jinhuang@mit.edu>