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ßNMR Progress Report
ISAC Forum, July 6, 2006
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Beam Usage
Polarized 8Li 28 keV June 22 July 5, 2006
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Prebeam Developments
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Recall Discharge Problem ßNMR platform
Light produced in scintillator target for BIAS gt
17 kV
Rates drop at BIAS gt 23 kV
Metal deposition on interior of Ceramic HV
Isolator
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Steps Taken(G. Morris and R. Abasalti)

1. Remove Ring Barrier Electrode
2. Polish metallization from isolator

Discharge problem gone
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Laser Problems
Solid State Pump Laser Spectra-Physics Millenia
Backup Ar Ion Pump (Alta)
Dye Laser
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Millenia Laser
Failed in April (first run) new head Failed
June 21 (no opportunity to test earlier) Used
Backup Coherent Argon Laser for first
week Millenia repaired for second week (Phil
Levy)
Need for access to laser room one week in advance
of the experiment (at least)
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Slow Start Up Chronology
20June ISAC power out 21June ISAC Control Room
Moves 21June 20h30 Nominal Start 22June
02h11 Proton Beam to ISAC 35µA 22June 18h10
7Li tunes done go to 8Li 24June 00h11 First
real data on bNQR 24June 08h00 switch to
bNMR 24June 15h41 First real data on bNMR
Need to make startup more routine and faster
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Rates
Rates are high Several 106 at the experiment
with polarizer iris at
4mm Main instability in rates seems to be Sodium
Cell Temperature Fluctuations Target Sparks
are very rare
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Example Rates
Neutral Beam Monitor Rates an epics diagnostic
Proton Rate
Laser Helicity Flips
DAQ Pulsing Beam
bNMR Rates (low field)
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Two Day Maintenance
No yield measurements Restarting the 8Li beam
goes very well (evening of June Tune is
reproducible
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Samples
Sapphire GaAsMn a dilute magnetic
semiconductor Ag/YBa2Cu3O7 heterostructure High
Resistivity Silicon
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Preliminary Results Vortex Broadening in Ag/YBCO
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Pinned Vortices at 500 G
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Spin Lattice Relaxation in Ag?
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Next Beam
July 12, 2006