Polarized 3He Target System

1
Polarized 3He Target System

• Overview
• Design
• Vertical Polarization
• Spin-Flip
• Oven/Ladder/Enclosure/Access
• Laser/Optics/Cells
• Polarimetry
• Safety/Documents
• Installation/Switch-over
• Milestone, Manpower and Responsibilities

2
3He Target Overview

3
Design Progress

• Progress (Estimated gt90 person-weeks 3 months
  ago)
• Completed items
• Layout for all four experiments
• New vertical Helmholtz coils and support
• New RF coils for vertical polarization
• New oven system
• Oven support in the target lab
• Target collimators
• Replacement support for horizontal Helmholtz
  coils
• New cells (with side pull-offs)
• Extended magnetic shielding on BigBite fringing
  field
• Conceptual design on laser optics lines
• Conceptual design on vertical Compass

4
Oven System

5
Oven being assembled in the target lab

6
Target Cell

7
Laser Optics

8
Remaining Items for Design

• Remaining design items (total lt 20 person-weeks)
• Main support Structure
• Supports for
• Target drive, Target Collimator, new RF coils,
  Ref. cell
• Target enclosure and windows
• Target ladder and pick-up coils
• Laser optics lines (including EPR,
  spectra-analyzer) and support
• Personnel access
• Safety interlock
• Compass mounts

9
Progress in the target lab

• Spin-flip test (mostly complete)
• RF sweep NMR on 3He works
• EPR works
• New support for horizontal Helmholtz coils
  installed
• New oven and support arrived, being assembled
• Two new cells manufactured and to be tested
• Cell characterization (density and window) setup
  ready
• Optical fibers and combiners ordered
• 5-to-1 combiners delivered, tested and problems
  found

10
Spin-Flip Test

11
RF sweep NMR on 3He

12
EPR

13
Planned tests in the target lab

• Install new oven, test
• Test new cells
• Characterizing new cells
• Test new components
• Test new optics
• RF sweep water calibration
• Combine polarization measurements with spin-flip
• Spin-flip signal to DAQ
• LabView communication with EPICS

14
Other Components

• Compass (Kentucky) Conceptual design complete
• complete design, manufacturing and test
• Vertical coils (order placed, delivery next
  month)
• setup in new target lab, align and field
  mapping
• then move to EEL target lab, integrate
  with horizontal coils
• Lasers 9 in hand, 2 spare diodes new vender
  narrow lasers
• Cells new contracts with Princeton/Mike Souza
• medium size (3) pumping chamber,
• production started, two in hand,
• plan to produce 1 cell every two weeks
• WM and UVa groups

15
Vertical Compass Conceptual Design

16
Safety and documents

• There are a number of safety aspects for the
  target
• Laser safety eye, skin, fire hazard, LSOP
• enclosure, alignment, eyewear, training
• High pressure glass cells explosion,
  radiation, OSP/RWP
• enclosure, windows, loop around pivot area
• cell handling face mask, eye and hearing
  protection
• Reference cell system high pressure, hydrogen
• Hot Surface/fire hazard from heating
• Electrical from power supplies
• Magnetic field
• All documents will be updated

17
Manpower

• Designer A. Gavalya, S. Esp (and help from
  others)
• Students C. Dutta (KY), J. Katich (WM), X. Zhan
  (MIT),
• Physicists T. Averett (WM, part-time), W.
  Korsch (KY, short-term visit), and J. P. Chen
  (JLab).
• Postdocs from WM, Duke
• Help from past students/postdocs.
• Off-site
• Cell production/testing at WM, UVa.
• Compass design/testing at Kentucky.

18
Responsibilities

• Overall J. P. Chen
• Design A. Gavalya/ J. P. Chen
• Vertical coils, holding field, oven system,
  ladder, support, cell characterization, reference
  cell, NMR
• J. Katich/T. Averett
• Spin-flip, EPR C. Dutta/W. Korsch
• Optics C. Dutta/J. P. Chen
• Software/Labview, communication with EPICS
• X. Zhan/B. Moffit
• Compass A. Kolarkar/W. Korsch
• Fringe field P. Brindza
• Safety, documents J. P. Chen

19
Installation, commissioning, switchover

• Coordinate with Ed Folts for installation 4-6
  week for the target
• Move to the hall, survey
• Move to pivot, survey, install components,
• Install optical line support, instrumentation,
  power cables
• Checkout magnets, measure field direction/survey
• Install ladder, cells, survey
• Install reference cell system, cooling jets
• Water calibration
• Laser safety inspection, switch to 3He, laser
  alignment
• Pumping up, check out spectra-analyzer, EPR
• Commissioning elastic 3He asymmetry (T and L)
• Switchover
• change cell, water calibration
• change optical line and check alignment, pump-up
• EPR, temperature test

20
Milestones for Polarized 3He

• Spin-Flip test done
• NMR/EPR system working done, keep improvement
• New oven ready for cell testing/characterization
  April 1
• Vertical coils test June 1
• Cell production 10 by July 1, 20 by Dec. 1
• New target structure Sept. 1
• Compass Sept. 1
• Laser optics line Oct. 1
• NMR FM water (optional) Oct. 1
• Complete system test Nov. 1
• Ready for installation Jan. 1, 2008