HALL-A STATUS REPORT

1. HALL-A STATUS REPORT Hall A Collaboration Meeting December 11-12, 2003 KEESDE JAGER JEFFERSON LABORATORY

2. GENERAL INFORMATION • Hall A 2003 Annual Report ready for distribution (Thanks Kathy!) • Heather will distribute download link or request for hardcopy • Office space • Hall leaders now responsible for office assignments in Trailer City • Dennis Skopik will distribute survey on TC occupancy (respond!) • Expansion of CEBAF Center on track for completion in spring 2006 • Cubicles on 2nd floor of counting house for people on site for experiment and summer students • Students: 35 theses completed • 32 active students (need new students!) • Borrel: ARC 231-233, Thursday 5:30-8 p.m. • sign up with Heather • last persons clean up before leaving

3. Hall A Approved Proposals PAC 4-24 • 29 Experiments completed • Backlog ~4 years (annual average for Hall A is ~90 days) • In 2003 Hall A only ran 35 days, but ~100 days scheduled for 2004

4. PROPOSALS to PAC-25 • PR04-002 Hadronization in Nuclei by Deep Inelastic Electron Scattering • PR04-007 Precision Measurement of the Electroproduction of πo near Threshold: a Test of Chiral QCD Dynamics • PR04-011 Photoproduction of q+ via the g + d -> q+ + L Reaction • PR04-012 High-resolution Study of the 1540 Exotic State • PR04-015 Precision Measurements of Longitudinal and Transverse Response Functions of Quasi-Elastic Electron Scattering in the Momentum Transfer Range 0.55 GeV/c < q < 0.9 GeV/c • PR04-018 Elastic Electron Scattering off 3He and 4He at Large Momentum Transfers • Allocation: 102 days (30 + 72 jeopardy) for 147 requested

5. LETTERS of INTENT to PAC-25 • LOI-04-001 Extration of GEp from a Double-Polarization Measurement of Two-body 3He Break-up • LOI-04-002 Measurement of the Spin and Parity of the Exotic Q+ via n(g,K-K+n) Reaction • LOI-04-004 Determining the Nature of the Q+ using Polarizaation Asymmetries • LOI-04-006 Measurement of the Q2-Dependence of the Axial-vector and Pseudoscalar Nucleon Form Factors from Q2 = 1 to 3 (GeV/c)2

6. Septum Magnets • Second magnet arrived early August • In both magnets bore size decreased and copper braids installed between coils and yoke • Second magnet showed leak in nitrogen system, but assumed small enough to allow normal operation • Second (left) magnet cooled down successfully and ramped to ~200 A (same initial value as with first) • Optimizing running conditions • Right magnet still not cooled down (possibly stuck check valve) • Installation complete by this weekend

7. Scheduled Experiments in Hall A ExpTitleSpokespersons 2003 Sep-Dec Installation of waterfall target, RICH detector and second septum magnet 2004 Jan/FebE94-107 High-Resolution 1p-Shell Hypernuclear Spectroscopy S. Frullani, F. Garibaldi, in the Valence Quark Region J. LeRose, P. Markowitz, T. Saito Mar/Apr Installation of cryotarget May-Jul E99-115 Constraining the Nuclear Strangeness Radius in PVES K. Kumar, D. Lhuillier E00-114 Parity Violation from 4He at Low Q2: D. Armstrong, R. Michaels A Clean Measurement of Rho Jul/Aug Removal of septa, installation of DVCS Aug-Oct E00-110 Deeply Virtual Compton Scattering at 6 GeV P. Bertin, C. Hyde-Wright, E03-106 DVCS on neutron R. Ransome, F. Sabatié Oct/Nov Installation of Big Bite Dec/Jan E01-015 Studying the Internal Small-Distance Structure of W. Bertozzi, E. Piasetzky, Nuclei via the Triple Coincidence 12C(e,e’pN) J. Watson, S. Wood

8. Publications (incl. submissions) in 2003 • S. Strauch et al., PRL 91, 052301 (2003), Polarization transfer in the 4He(e,e’p)3H reaction up to Q2 = 2.6 (GeV/c)2 • L.Y. Zhu et al., PRL 91, 022003 (2003, Cross-section measurement of charged-pion photoproduction from hydrogen and deuterium • X. Zheng et al., PRL accepted, Precision measurement of the neutron spin asymmetry A1n and spin-flavor decomposition in the valence quark region • M. Amarian et al., PRL accepted, Q2 evolution of the neutron spin structure moments using a 3He target • W. Xu et al., PRC 67, 012201R (2003), PWIA Extraction of the neutron magnetic form factor from quasi-elastic polarized 3He(e,e’) at Q2= 0.3 to 0.6 (GeV/c)2 • X. Jiang et al., PRC 67, 028201 (2003), Search for neutral baryon resonances below pion threshold • D. Dutta et al., PRC 68, 021001 (2003), Nuclear transparency with the gn -> p-p process in 4He • M. Sargsian et al., J. Phys. G 29, R1 (2003), Hadrons in the nuclear medium • D. Higinbotham, PRC submitted, Importance of Coulomb corrections in the extraction of the proton form factors • V. Punjabi et al, PRC submitted, Proton elastic form factor ratios to Q2=3.5 GeV2 by polarization transfer • J. Alcorn et al., NIM A accepted, Basic instrumentation for Hall A at Jefferson Lab • Total to date: PRL/PLB 18, other ref. journals 10 + NIM 7 (plus two submissions) • Directly related to approved proposals: PRL/PLB 16, PRC 6 (29 completed exp) • Four experiments completed more than 2 years ago without any publication yet

9. ARCHIVAL PAPERS • E93-027: GEp/GMp by polarization transfer on the proton submitted (waiting for response to referee comments) • General Hall A NIM instrumentation paper accepted • Other archival papers in preparation • E91-026: A(Q2) and B(Q2) for the deuteron • E95-001: inclusive quasi-elastic scattering from 3He • E89-003: 16O(e,e’p) draft circulating • E91-010: HAPPEX draft circulating

10. Summary • Hall A research program vibrant • Many exciting new results • However, don’t forget archival publications • Septum magnets are concern, • but required for series of high-impact experiments • Scheduling for next five years will be difficult • Strong support from DOE/OSC, but no CD0 yet • Keep up the good work!