HALL-A STATUS REPORT

1
HALL-A STATUS REPORT

• Hall A Collaboration Meeting
• December 11-12, 2003
• KEES DE 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 530-8 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 po near Threshold a Test of
  Chiral QCD Dynamics
• PR04-011 Photoproduction of q via the g d -gt
  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 lt q lt 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-Kn) 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

• Exp Title Spokespersons
• 2003
• Sep-Dec Installation of waterfall target, RICH
  detector and second septum magnet
• 2004
• Jan/Feb E94-107 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,

8
Publications (incl. submissions) in 2003

• S. Strauch et al., PRL 91, 052301 (2003),
  Polarization transfer in the 4He(e,ep)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 -gt 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 Q23.5 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,ep) draft circulating
• E91-010 HAPPEX draft circulating

10
Summary

• Hall A research program vibrant
• Many exciting new results
• However, dont 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!