18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A April 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 (E and PR )

SIDIS and TMD and Asymmetries 18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 2 Transversity PDF Sivers and Pretzelosity TMD (  Collins and unpolarized FF) PDF/TMD and FF

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 3 Hepex From DIS2010 From Pappalardo / Transversity 2008 Collins Moments on proton/deuteron COMPASS/deuteron proton Proton: K- and  - with opposite sign, strong flavor dependence (but K errors significant)! K+ and  + consistent with u dominance COMPASS compatible with HERMES Deuteron: consistent with 0, expected asymmetry on neutron as large as on proton Weak Q 2 dependence Larger effects at larger x

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 4 DIS2010 COMPASS/proton Sivers Moments on proton/deuteron PRL103(2009) Proton: K+ twice  + conflict with u dominance expectation K- and  - 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 HERMES on p New data welcome!

JLab Accelerator Facility Today 18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 5 6 GeV CEBAF (< 2013) Max Current: 200  A Max Energy: GeV Long. Polarization: 85% 6 GeV CEBAF (< 2013) Max Current: 200  A Max Energy: GeV Long. Polarization: 85%

6 Hall A Two High Momentum Resolution + one large angular acceptance spectrometers Dedicated neutron and gamma detectors High beam currents (>100  A), lumi cm -2 s -1 Control of the beam parameters (polarization, position …) 3 He T/L Polarized target, high flexibility unpol. from H to Pb Large and flexible installations Hall A today 2 High Resolution Spectrometers BigBite 3He polarized target 18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 7 Transversity on neutron: Hall A experimental setup Beam e-:  5.9 GeV, 15  A Neutron Target:  High pressure polarized 3 He pol. 65%, 50 mg/cm 2 x 40 cm  Luminosity: /s/cm 2 Electron Arm (BigBite):  E’=0.7  2.2 GeV, =30°,  =64 msr Hadron Arm (HRS Left):  P h =2.35 GeV/c ± 5%, =30°,  =6 msr, p/K ID Kinematic region:   Q 2  ~ 2.2 GeV 2, x ~ 0.13  0.45,  z  ~ 0.5 Measure Collins, Sivers and Pretzelosity Beam e-:  5.9 GeV, 15  A Neutron Target:  High pressure polarized 3 He pol. 65%, 50 mg/cm 2 x 40 cm  Luminosity: /s/cm 2 Electron Arm (BigBite):  E’=0.7  2.2 GeV, =30°,  =64 msr Hadron Arm (HRS Left):  P h =2.35 GeV/c ± 5%, =30°,  =6 msr, p/K ID Kinematic region:   Q 2  ~ 2.2 GeV 2, x ~ 0.13  0.45,  z  ~ 0.5 Measure Collins, Sivers and Pretzelosity Experiment: E Data Taking: Nov/08 – Feb/09 Experiment: E Data Taking: Nov/08 – Feb/09 E e+ 3 He  →e’+  (K)  +X

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 8 3 He (n) Polarized Target Polarized 3 He ~ polarized neutron target Use 3 COMET lasers (narrow line, high power) for optical pumping of Rb vapor Fast spin exchange (via K) by 3 He hyperfine interaction in oven; small part of N 2 to quench soft photon depolarization of Rb Polarized 3 He diffuses to the target chamber Transverse Horizontal (In-plane) and Vertical orientations 20 minute spin flip NMR and EPR polarimetries Superior performances: –Steady 65% 15 uA beam (world record)

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 9 3 He Asymmetries on  DIS: Q 2 >1, W>2.3, M x >1.6, 0.3<z<0.7 MxMx Preliminary E06-010

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 10 Preliminary Hadron Identification Aerogel Cherenkov Counter –  rejection > 98% Time of Flight –K/  separation at 4  RICH proximity focusing detector –K/  separation at 3.8  data from APS2010 / Y. Wang P h = 2.33 – 2.47 GeV/c Strongest quality cuts

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 11 CEBAF 12 GeV upgrade CHL-2 Upgrade magnets and power supplies add Hall D (and beam line) 12 GeV CEBAF (>2013) Max Current: 90  A Max Energy Hall A,B,C: 10.9 GeV Max Energy Hall D: 12 GeV Long. Polarization: 75-85% 6 GeV CEBAF (< 2013) Max Current: 200  A Max Energy: GeV Long. Polarization: 85%

12 Hall A in 2013 Hall 12 GeV + 1 large angular and momentum spectrometer for high luminosity experimento, with hadron ID New beam line Improved BigBite Spectrometer (with GEM detectors) + lumi cm -2 s -1 (new DAQ, improved targets) + higher targets thickness hallaweb.jlab.org Super BigBite + Form Factors at high Q 2 and more Large luminosity Moderate acceptance Forward angles Reconfigurable detectors Large luminosity Moderate acceptance Forward angles Reconfigurable detectors 18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A Gep5 configuration

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 13 Measure SIDIS processes n  (e,e’   )X and n  (e,e’K  )X –Extract Sivers, Collins and Pretzelosity asymmetries on  and K with high statistics –Provide 2D binning (at least) on the relevant variables: x, P  and z, for both hadrons –Provide Q 2 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) PR : SIDIS on  and K (PAC /2009) Similar layout of the 6GeV experiment at higher luminosity and acceptance HRS replaced by a new large acceptance spectrometer (SBS), improved target Proposal: Conditionally approved

HERMES RICH 18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A GeV SIDIS: Experimental Setup Beam: 50  A, E=8.8 and 11 GeV (80% long. Pol.) Target: 65% polarized 3 He  GEn/E  Luminosity: 1.4×10 37 cm -2 s -1, 0.05 sr e+ 3 He  →e’+  (K)  +X BB: e-arm at 30 o  = 45 msr GEM Tracker Gas Cherenkov Shower  GMn/E SBS:h-arm at 14 o  = 50 msr GEM tracker excellent PID / RICH Hadron CALO Most of the equipments from EM Form-Factors experiments Event rate : ~10 4 ×HERMES 60 days of production expected stat. accuracy: 1/10 of proton HERMES Synergies with other approved experiments

New target 18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 15 A new 3 He pol. target Current 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

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 16 Hadron PID HERMES RICH Very stable performance (  n/(n aerogel -1)= 1%, 9 years) Stored at UVa under safe/controlled conditions (also additional wall of spare Aerogel) 5.5 GeV K GeV e- 1.5 GeV  - REAL DATA from NIMA 479 (2002) 511 C4F10 gas  De Leo talk on Wed.

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A GeV SIDIS: Q 2 coverage Current Transversity Exp. E Prop. Exp. E beam = 8.8 GeV Prop. Exp. E beam = 11.0 GeV We will investigate the Q 2 dependence of the Sivers and Collins functions, with overlap in the region of HERMES; reveal higher twist effects ?. Analysis of the Q 2 effect will use also the results of 6 GeV E Transversity experiment 2.4<W<4 GeV * 0.1<P  <1.2 GeV 0.2<z< <y<0.9 *

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 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

18 Oct 2010 / PSHP / Frascati E. Cisbani: JLab/Hall A 19 Summary 6 GeV “Transversity” Experiment on  and K (E06-010) –Data taken on n  in 3 months (Nov/08 – Feb/09) –Almost completed analysis for  -SSA (preliminary K asymmetries already measured) –New results to be released soon 12 GeV Kaon in SIDIS (PR ) –SBS-SIDIS:  and K SSA on 3 He  target with significantly improved statistics (conditionally approved) –will benefit of JLab luminosity, new 3 He polarized target and new large acceptance spectrometer (SBS)