mom report

MOM Report

Paul SolerMICE Operations Manager

University of Glasgow

MICOApril 26, 2010

April 26, 2010 Commissioning Needs-Soler 2

Commissioning Needs•Decay Solenoid: further update

—Linde refrigerator developed fault: large N2 impurity level

—Linde engineer changed charcoal in gas panel adsorber, 23-26 March

—Compressor shaft seal was then thought to be the culprit —HPC (local agents for Linde) tried to extract seal but had to

dismantle compressor—Whole compressor replaced Tuesday 20 April —Matt measured impurity level on Thursday-Friday 22-23 April

(see next slide) with cryo-adsorber disconnected – N2 level rises at ~3 ppm/hour, while H20 impurity level remains constant

—Mike thinks that we need to focus attention on adsorber and gas panel where there might be a leak since vacuum has never been very good in the adsorber – is it possible that one of the valves or piping has a leak when system is running?

—Run leak tests with running system again (from this week)


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22/04/201009:36

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H2O (ppm)

N2 (ppm)

Commissioning Needs

N2, H20 impurity levels


Target•Target

— Investigation of target forces— Emily Longhi (from Diamond) working to find if magnetic centre

= geometric centre

Magnetic Centre

-40x10-3

-20

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Fiel

d al

ong

stat

or [

5*T]

4550450044504400Position in Device [mm]

Horizontal Field Longitudinal Field Vertical Field


TargetMechanical/Optical Measurements

Bearing Tool

Hall Probe

A B

Bore

D

C

Optical Faro

A 5.6 +/-0.1AB=0.33

B 5.89 +/-0.06

C 6.57 +/-0.05CD=0.94

D 7.47 +/-0.05

•Target — Mismatch between

geometric and magnetic centre: ~0.5 mm

— Is this the smoking for lateral forces in target shaft?


Detectors•Detectors

— Luminosity Monitoro Successful run on Tuesday 20 April (runs 1538-1555) for LM gate width studies: data 10, 20, 30, 40 ns gates for ~0.4 V, 1 V and 1.3 V – being analysed now

— Trackero Nothing new to report

•Detectors — CKOV,TOF0, TOF1, TOF2, KL: all powered up and ready to go

o Request to have new TOF calibration with defocused beam to populate counters on the edge of acceptance

o Ran this weekend 23-26 April for TOF calibration 10,000 actuations with 300 MeV pion beam and 1,000 actuations with 300 MeV positron beam

— Beam Profile Monitors: also running•Beam Magnets

— Had lots of problems with flow rate meters on power supplies during weekend run. Q6 and Q7 kept on tripping because of flow problems (typically every 10 minutes!) – maybe the flow rates are too high (recently changed to 60-65 l/min)

— Flow rate trips were annoying but maybe not too important for TOF claibration run. However, this would be an unacceptable running mode if we were doing emittance measurement runs.

— Need to purchase new flow rate meters•Hall work:

— PPS electrical system installation has started with DL staff


Summary last week’s runs•Machine development period: 12-19 April

—One shift (18:00-1:30) on Friday 16 April for Luminosity Monitor gate width studies: all hardware worked well but had to abort due to bad ISIS beam

•ISIS run: 20 April – 28 May— Shift 20 April: rescheduled from Friday for LM gate studies

o Run successful: took data 10, 20, 30, 40 ns gates for ~0.4 V, 1 V and 1.3 V – being analysed now

— Weekend 23-25 Aprilo Performed TOF0,1,2 calibration with blown up defocused beam – 10,000 actuations of 300 MeV pi+ beam with defocused Q7, Q8, Q9 by 20%, 20%, 40%, and 1,000 actuations with e+ beam.

o Friday 23 April running was hampered by EPICS problem – a change made to the slew rate to ramp up magnets was not communicated to MOM and had a bug – it always set the current at 0 A

o After finding cause of problem, old EPICS version was reinstalled and magnets were then successfully ramped up.

o Since it was 11:00 pm when this was fixed, we aborted run to return Saturday


Summary last week’s runs•ISIS run: 20 April – 28 May (cont.)

— Weekend 23-25 April (cont.)o Saturday 24 April: successful TOF calibration run with 300 MeV pi+ beam: 10,000 actuations with runs 1558-1580

o Beamloss profile flatter by entering earlier (0010000100 delay)-see plot

o Sunday 25 April: tried to run 1,000 actuations of a 300 MeV e+ beam with defocused Q6, Q7, Q8

o Unfortunately I forgot to raise beam stop, so the trigger rate was very low (~2 per spill)!!!! Since I did not know what rate to expect we ran for four hours in this way before realising mistake (runs 1581-1589)

o Then, we raised beam stop and runs 1590-1591 contain the good positron runs for TOF calibration

o Other issue: we need to make sure target calibrations (every 10,000 actuations) can be done by BLOC so as not to stop long weekend runs

— Conclusion:o Apart from a few niggling problems (EPICS problem, Q6 and Q7 trips, and the bad positron run) I think weekend running was a success and allows for more efficient data taking.

o I propose we continue with runs on weekends.


Summary last week’s runs

Beam loss profile


Run plan•ISIS run: 20 April – 28 May (cont.)

— Chris Roger takes over as MOM from today so he should comment on schedule. However, we had a preliminary plan from VC that we could follow

— Weekend 30 April – 3 May:o If Yordan needs more data for TOF calibration then we could run some more (he would have to tell us how much more)

o However, if TOF calibration OK, then continue with plan: proton absorber tests – move different thickness of absorber to compare particle rate vs absorber thickness – Marco should say what are best settings and how much statistics

— Weekend 7-10 May: likely that the Decay Solenoid will not be ready

o Propose to continue with target scan: delay target vs depth (ie acceleration) to try and flatten spill and reduce pileup and beam overlaps.- suggestion for weekend of 7-10 May (Do we need to wait for DS to be ready?)

o There was a successful flattening of beamloss profile during last weekend but might need to do it more systematically


Run plan•ISIS run: 20 April – 28 May (cont.)

— Once Decay Solenoid is ready:o Work our way through Step I physics programme: matrix of emittance (4, 6, 10) vs momentum (160, 200, 240 MeV/c) with all detectors on – 15-17 May, 22-24 May

o Statistics for each point? ~105 muons?

•ISIS shutdown: 29 May-6 June•Next machine development period: 7-21 June

— Request further activation run: 16 hours with 4V beamloss?

•ISIS users run: 22 June – 12 August— Continue with Step I programme of emittance vs momentum

matrix.— Can cope with only running on weekends for the time being but

if we are running out of time to complete programme, we could also schedule runs during the week for this period

•Machine Physics: 13-15 August•Long shutdown: 16 August 2010-30 January 2011

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