Date post: | 01-Apr-2015 |
Category: |
Documents |
Upload: | brendan-pressey |
View: | 217 times |
Download: | 0 times |
Total Loss Monitor ReportAll experimenters meeting5/12/14A. Leveling
A. Leveling
2 5/12/2014
TLM detector cable
Chipmunk
Chipmunk electrometer(blue box)
Chipmunk ion chamber
Prelude
A. Leveling
3 5/12/2014
3 parallel TLM detectors125’250’350’
PbarA2B7
magnet
TLM providescontinuous, in-tunnel
coverage
Chipmunks providediscrete, above-ground
coverage
Prelude
A. Leveling
4
The problem: Radiation Safety System (RSS) at pbar service buildings
includes 42 Chipmunks Adequate for the 8 GeV, 13 watt pbar ops
RSS needs to be extended for 8 GeV, 8 kW mu2e operation – about 200 units
Unit cost is about $10k or total of $2M Includes detector construction, doghouses, electrical
installation M&S, RSS infrastructure
Would add tremendous complexity, e.g., Chipmunks require annual calibration
RSS testing
5/12/2014
A. Leveling
5
Why TLMs? Following a Director’s review in May 2011 for mu2e CD1,
ESH&Q Section Head suggested that we consider Long Detectors in lieu of Chipmunks
Long detectors have a long history at FNAL; they have been highly regarded by their proponents Switchyard
Booster
NuMI
External beam lines
The obstacle: long detectors could not serve in the capacity of a CREDITED CONTROL for the Accelerator Safety Envelope
5/12/2014
A. Leveling
6
Development history Work to characterize long detector
response began immediately in May 2011
A long series of studies was conducted at pbar to characterize detector response as a function of 8 GeV beam loss
Detector response curves for the ion chamber region were developed
5/12/2014
A. Leveling
7
Development history BLM electrometers were used in early studies
with disappointing results
A Chipmunk, sans ion chamber, was then used (aka blue box, electrometer) Provided linear, predictable response
The blue box was already a critical component of the existing RSS!
Electrometer: collects and measures charge produced in the detector
5/12/2014
A. Leveling
8
TLM electrometer development The job was simply to mimic
the features of the existingChipmunk Provide a heartbeat function
Failsafe design
Key problem was to develop the required dynamic range, not just for mu2e but for all conceivable applications – Booster, MI, NuMI, etc.
A couple of new design features were created to eliminate lost data collected by the site wide Radiation Monitoring System (MUX)
5/12/2014
A. Leveling
9
TLM detector/electrometer testing 3 electrometers were designed The chosen design has been in service
in wide variety of applications starting in December 2012 Linac – 10 foot detector Booster – 180 foot detector (P10-12) Pbar – 125’, 250’, and 350’ detectors NuMI – four 200’ connected in series NML – 10 foot detector
5/12/2014
A. Leveling
10
How does it work? The shielding thickness available at a
given location, along with desired occupancy, determine upper limit of allowable beam loss
The TLM trip level is determined from our knowledge of detector response as a function of beam energy and intensity Developed over the past 3 years with
measurements
5/12/2014
A. Leveling
11
Progress over the past year Electrometer module development and
construction – completed end of April 2013 Prototype and detector testing - May 2013
to present Documentation submitted to AD ES&H -
October 2013 ES&H Section Approval - May 2014
Allows $2M risk for mu2e to be retired Cost of TLM systems about $200k
5/12/2014
A. Leveling
12
What does preliminary approval mean? We can build, install, AND connect systems to the
RSS
First application is Booster A system covering the entire ring will be installed
later this year
A parallel section of detector already installed in Booster (P10-12) will be compared with its new companion for a period of 1 year
Assuming required documentation is submitted and testing period goes well, we could be expect FINAL APPROVAL in September 2015
5/12/2014
A. Leveling
13
Other applications to be studied before final approval NuMI beam line
Already under study since 9/2013 MI52, slow resonant extraction at MI MI30 collimation section ASTA
By the time TLMs are required for mu2e, their use will have been well established
5/12/2014
A. Leveling
14
Extra slides
5/12/2014
A. Leveling
15 5/12/2014