Understanding the Three-Body Nuclear System: Asymmetry Measurements in Quasi-Elastic

Ge JinUniversity of VirginiaFor the E05-102 Collaboration

p)e',e(He and d)'e,e(He 33

Deuterium Spin Structure

Spin-1 Particle, 2 spin-1/2 Nucleons (Proton and Neutron)

Angular Momentum l=0 l=2 ~90% ~10%

Asymmetry Measurements at NIKHEF A sign flip of asymmetry

with the increase of missing momentum gave an indication of the existence of D state

Sign flip happened at around Fermi momentum of deuterium nucleus

p)n'e,e(D

I. Passchier et al., Phys. Rev. Lett. 88 (2002) 102302.

3He Spin Structure: Will Similar Things Happen with Asymmetry?

Spin-1/2 Particle, 3 spin-1/2 Nucleons (Proton and Neutron)

Angular Momentum l=0 l=0 l=2 ~90% ~1-2% ~8%

EffectiveNeutronTarget

Theoretically, Yes, according to Faddeev Calculation on p)e',e(He and d)'e,e(He 33

Our Lack of Knowledge of 3He is Affecting Other JLab Experiments! JLab experiment E99-

117 measured neutron asymmetry A1

n in DIS region, the leading error other than statistical is caused by uncertainty in the effective proton and neutron polarization in 3He

X. Zheng et al., Phys. Rev. C 70, 065207(2004)

3He Target

Hybrid K-Rb spin exchange optical pumping

High in-beam polarization ~60% Narrow band-width laser

Separating protons and deuterons

Momentum vs time-of-flight

Scintillator planes energy deposition

BigBite wire chambers:optics and tracking

momentum reaction z

Conclusion Deuterium asymmetry: experiment and

theories (N-N potential theory) 3He asymmetry: theories but no

experiment Experimental apparatus

High resolution spectrometer (HRS) BigBite spectrometer Polarized 3He target

Analysis ongoing

Graduate StudentsG. Jin, University of Virginia

E. Long, Kent State UniversityM. Mihovilovič, Jožef Stefan Institute

Y. Zhang, Lanzhou University

Run CoordinatorsA. Camsonne, Jefferson Lab

P. Monaghan, Hampton UniversityS. Riordan, University of VirginiaB. Sawatzky, Temple UniversityR. Subedi, University of Virginia

V. Sulkosky, MITY. Qiang, Duke University

B. Zhao, College of William and Mary

S. GolgeO. Hansen

T. HolmstromJ. Huang

H. IbrahimE. JensenM. JonesH. KangJ. Katich

C. W. KeesP. King

J. LeRoseR. Lindgren

H. LuW. Luo

K. AlladaB. AndersonJ. R. M. AnnandW. BoeglinP. BradshawM. CananC. ChenR. De LeoX. DengA. DeurC. DuttaL. El FassiD. FlayF. GaribaldiH. GaoR. Gilman

P. MarkowitzM. MezianeR. Michaels

B. MoffitN. MuangmaH. P. Khanal

K. PanD. Parno

E. PiasetzkyP. Pradshaw

M. PosikA. J. R. Puckett

X. QianX. Qui

A. Saha

Thanks to the Hall A Quai-ElasticFamily Experiments

SpokespersonsT. Averett, College of William and Mary (E05-015, E08-05)

J. P. Chen, Jefferson Lab (E05-015)S. Gilad, MIT (E05-102)

D. Higinbotham, Jefferson Lab (E05-102, E08-005)X. Jiang, Rutgers University (E05-015)

W. Korsch, University of Kentucky (E05-102)B. E. Norum, University of Virginia (E05-102)

S. Sirca, University of Ljubljana (E05-102)V. Sulkosky, MIT (E08-005)

E05-015,E08-005,and E05-102

CollaborationF. Salvatore

M. ShabestariA. ShahinyanB. Shoenrock

J. St. JohnA. Tobias

W. TiremanG. M. Urciuoli

D. WangK. WangJ. Watson

B. WojtsekhowskiZ. Ye

X. ZhanX. Zheng

L. Zhu