1. Overview of Onsite Progress Jian-ping Chen g 2 p /G ep Collabroation Meeting

2. REGION 1 REGION 2REGION 3 REG 4 REGION 5 Slow Raster FZ1 FixedStand FZ2 Telescoping Stand DUMP TARGET Polarized Solid NH 3 Target (Hall C/UVa target) Target material irradiation Beamline (Similar to Hall C) Magnetic Chicane/Beamline modifications. Low beam current BCM/BPMs Slow Raster Hall A Engineering/Design Local Beam Dump Hall Infra-structure Scattering Chamber/ Target/magnet mount Septum Magnets Simulations/Optics/Spectrometer/Detectors/QAD… BPMs Use existing equipments Hall C beamline/target Keep change minimum modify the existing PREX septa use simple local beam dump Major equipments for g 2 p /G E p experiments Septa/HRS

3. Significant Progress in Beam Line System (T. Michalski, B. Dillon-Townes) Overview conceptual design completed Region 1 and Region 2 design drawings completed Region 3 main items identified and detail design on-going Existing hardware items (magnets, raster, power supplies) located New items (BPM electronics, Harps, BCM, BD magnets, …) Target Progress (C. Keith/ D. Crabb) Conceptual design Rotating seal Pumps ordered New fridge at UVa tested (along with existing target materials and other systems) need to manufacture one fridge at JLab Target material irriadiation: will do it at NIST Magnet is being shipped from Oxford back to JLab? Hall A infrastructure, Beam dump, Septum (A. Gavalya, R. Wines) Setup at the pivot area for the target Beam dump Septum Scattering chamber/ layout/ interferences 3 rd Arm for polarization monitoring Simulations Overview of Progress

4. 3.3 GeV, 12.5 deg 2.2 GeV, 15 deg 3.3 GeV, 6 deg 2.2 GeV, 6 deg 1.6 GeV, 6 deg 1.1 GeV, 6 deg Polarized beam: 50-130 nA up to 5 uA? for optics, 30 uA ? for Compton Polarized NH 3 target Slow Raster 25 mm diameter G e p configuration is now basically g 2 p at the elastic setting Two configurations: with septa (6 degree) (target at 87 cm upstream) and without septa (12.5 and 15 degrees) (target at original pivot) g 2 p needs target at 90 degrees for all and 0 degree for 3.3 GeV G E p needs target at 80 degree Kinematic Settings (Last Meeting)

5. 3.3 GeV, 12.5 deg 2.2 GeV, 12.5 deg 3.3 GeV, 6 deg 2.2 GeV, 6 deg 1.6 GeV, 6 deg 1.1 GeV, 6 deg Polarized beam: 50-130 nA up to 1 uA for optics, (also for Compton?) Polarized NH 3 target Slow Raster 20-25 mm diameter G e p configuration is basically g 2 p at the elastic setting Two configurations: with septa (6 degree) (target at 87 cm upstream) and without septa (12.5 and 15 degrees) (target at original pivot) G 2 p : target at 90 degrees for all and 0 degree for 3.3 GeV G E p : target at 20 degree? Kinematic Settings (Now)

6. Cost, mostly consistent with initial estimation, some increase due to new items A) Beam line procurement: 14 BMP electronics harps (can not use the existing French harps) Beam line manpower: the two items above + software group B) Target group estimation, procurement increased from 80 K to 140K. FY11, continuing resolution addition funding from DOE (promised) not here yet. User pledged contribution to procurement : $ 80K to Engineering/Installation: ? Total: $140K Will need user to honor the pledges. Manpower cost will be supplied from within JLab. Need help from user manpower Budget and User Contributions

7. Questions and Issues Should we do Compton with 1 uA, straight-through, how many times? How should we do optcis study-? What optics target(s) should we have? How to do the polarization monitoring (3 rd arm)? Should we do a field map at EEL? Should we add some iron plates to study the effect? Should we and how to measure field direction? Should we do a field map in Hall A (combining target/septa)? …?

8. Onsite User/Hall A People Power PhD Students: Pengjia Zhu (USTC, advisor: Yunxiu Ye), 3 rd year, onsite, (beamline, target) Min Huang (Duke, Haiyan Gao), 3 rd year, onsite, (simulation, optics) Chai Gu (UVa, Nilanga Liyanaga), 2 nd year, onsite from 2/2011 Melissa Cummings (W&M, Todd Averett), 2 nd year, onsite from 5/2011 A student from Temple (Zein-Eddine Meziani), 2 nd year, onsite from 5/2011? Name? (New Hampshire, Karl Slifer), 1 st year, onsite from? ? Postdocs: Kalyan Allada (Hall A), beamline, 3 rd arm Jixie Zhang (Hall A): simulation, optics Xiaohui Zhan (Argonne) (onsite from 2/2011), target? Narbe Kalantarians(UVa): target Hovhannes Baghdasaryan (UVa) ? Sarah Philips (New Hampshire) ? ? Physicists: Jian-ping Chen (Hall A): Project manager, overall coordination Alexandre Camsonne (Hall A): Beam line, DAQ, … Karl Slifer (New Hampershire): Overall consideration, run plan, … Doug Higinbotham (Hall A) (will be more available after SRC experiments?) Guy Ron (LBNL)? ?