1. Polarized He3 Target Upgrade (Stage I) for A1n/d2n
Stage I goal:
30 uA on 40 cm , ~10 atm, L ~ 2.2x1036 cm-2s-1
In-beam polarization ~60%,
Polarization measurement precision~ 3%
Experiments: A1n Hall C (high impact), d2n in Hall C
Approaches:
Re-use existing Helmholtz coils and most existing hardware, electronics and optics
Convection flow
Target cell, pumping chamber size 3.5”, glass cell (optional: one metal-end window cell to prepare for future experiments, possibly can take higher current)
Polarimetry ~ aim for 3%, Pulse NMR calibrated with AFP NMR (pNMR at both transfer tube and target chamber, need good field gradient), pNMR is not absolutely required by it can be done more often online; absolute calibration with EPR (need 2% kappa_0) and AFP-NMR with water calibration in the Hall (is water calib in the hall optional or required? Will at least make it work in the target lab)
Modification to Hall C pivot area and new platform/laser optics line
Project mostly complete.
Started preparation for hall installation
identifying installation requirements: space, shielding, electronics, cables, …

2. Stage I Progress Summary
Engineering/Design:
target design complete
installation design ongoing
Field gradients at target area:
Tosca for Bender field at target region done
work just started to have target field
combined with and Bender magnet
Target cells
prototyping convection cell extensively tested,
cell production started
1st good cell: lifetime > 48 hours, tested at Uva
five cell production ordered and started, will need more eventually (need 2nd round of production), testing at UVa+JLab
water cell production?
Reference cells system/gas control (Todd?)
Ref cell production? (have one 40-cm old one)
Spare parts (electronics, etc? depending on funding… may need university support, – need wish list)

3. Stage I Progress Summary (cont.)
New Oven Manufactured/Installed/Tested
Lasers/long optical fibers:
five Raytum lasers delivered/tested
will order more as spares and for future
long fibers delivered, tested, conduit installed
5-1 combiners ordered, work with vender
to resolve issues
polarization compensation study complete
Polarimetry:
pulse NMR systematic study (Nguyen Ton)
absolute calibration with EPR study (Kai Jin)
0 measurement (UVa/W&M) in progress

4. Vertical Correction Coils

5. Gradient from HB Tosca Modeling by Steven Lassiter

6. Target Control System Layout/Electronics/Cables

7. ERR Charges
1) Maximum Current and Target dimensions; 30 uA/40 cm (Higher for optics?)
2.a) see previous slides
2.b) Configuration is known, including laser Interlock system in the hall.
LSOP started discuss with Bert.
3) See previous slides: HB field under control. Looking into HB steel effect.
5) Need students working on target (two UVa students are ramping down their effort on the target), Reference system: Todd?
8) LSOP see 2.b)