Transcript Spectrometer Solenoid Update Michael S. Zisman Center for Beam Physics Accelerator & Fusion Research Division Lawrence Berkeley National Laboratory MICO Meeting—RAL September 15, 2008

Spectrometer Solenoid Update
Michael S. Zisman
Center for Beam Physics
Accelerator & Fusion Research Division
Lawrence Berkeley National Laboratory
MICO Meeting—RAL
September 15, 2008
Status (1)
• MZ, MAG, and SV visited vendor on Friday, Sept. 12
• Discussed options and agreed upon plan to move forward
— complete magnet 2 first, then open magnet 1 and fix it
— modifications to include
o improved thermal connection between stage 1 of coolers and shield
o improved design of liquid He piping to minimize risk of frozen nitrogen
plug
– enter cold mass vessel from 7 o’clock position (now it is 6 o’clock)
– enlarge He tubes to 0.5-in.
– redesign manifold to eliminate low spots
o generate written cool-down procedure
o modify stand to eliminate interference with iron disk bracket
– favored approach will make magnet stands for magnets 1 and 2 have
different positions
 is this an issue for interface with false floor?
September 15, 2008
MICO: Zisman
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Status (2)
• Magnet 1 will subsequently get the same modifications
— will also correct alignment errors when magnet is opened up
• Schedule
— aim for completing magnet 2 by early November
o somewhat skeptical that this will happen on time
— magnet 1 should be ready about 2 months after magnet 2
• Implications of schedule
— it does not seem likely that magnet 2 could be run at RAL before the end
of the year even if we skip magnetic measurements at FNAL
o unless we can shorten the 6-week preparation time by several weeks
– this potentially leads to resource conflicts with decay solenoid repair
if that cannot be accomplished in October
— Executive Board needs to decide priorities
September 15, 2008
MICO: Zisman
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Commissioning Needs (1)
• Need to get Decay Solenoid power supply operating
— and then begin tests of magnet
o use signs and barricades if no indicator light
— need DL help for this
— potential to interfere with DSA roof job if we’re not careful
o could do off-hours after PSU is fully operable
• Need to develop optics for electron beam (Tilley,
Apollonio)
— used for calibrating CKOV and TOFs
o must extend all the way past Q9 (i.e., into the Hall)
• Need to extend permission to operate target parasitically
during ISIS user run
September 15, 2008
MICO: Zisman
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Commissioning Needs (2)
• Need to make beam loss measurements to compare with
model calculations (Adams, Dobbs)
— also need extended run at “enhanced” loss rates to determine activation
effects of a given instantaneous loss rate
• Need to test MBS once installed
— logic of interlock to ISIS needs definition
o maybe already done (?)
• Need to incorporate key ISIS BLMs and BPMs into MICE
target data stream
— and eventually into DAQ stream
— cables are available, but need to be connected on both ends
September 15, 2008
MICO: Zisman
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Issues
• Need suitable lock-off on DS PSU (safety issue)
...hope springs eternal
o ideally, should look the same as the other big PSUs
• Need network access to e-log from RAL-VIS network
— Gareth Smith (PPD) trying to get this sorted out
— this is a real pain and MUST get fixed soon!
• Need to decide how to proceed with off-line target
— best guess: magnetic and mechanical axes are misaligned
o need to confirm this or find another explanation
– it is clear that we still do not have sufficient understanding of
target requirements
• Need to resolve need to lock Hall when target operating
and MBS is closed
September 15, 2008
MICO: Zisman
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