commissioning lhc beam instrumentation for nominal bunch intensities
DESCRIPTION
Commissioning LHC Beam Instrumentation for Nominal Bunch Intensities. Beam Commissioning Working Group June 15 th 2010 Rhodri Jones (CERN Beam Instrumentation Group). High Intensity BI LHC Commissioning. Report from 2 MD periods May 28 th : 4 hours 1 st go at - PowerPoint PPT PresentationTRANSCRIPT
LHC Beam Instrumentation - First Results & Next Steps
Commissioning LHC Beam Instrumentation for Nominal Bunch IntensitiesBeam Commissioning Working GroupJune 15th 2010
Rhodri Jones(CERN Beam Instrumentation Group)
Report from 2 MD periodsMay 28th : 4 hours1st go atBPM reading v intensity studiesStudies on DCCT dependence on fill patternCalibration of various Fast BCT modesJune 8th : 7 hours2nd go atBPM reading v intensity studiesStudies on DCCT dependence on fill patternsCalibration of various Fact BCT modes1st go atWire scanner timing calibrationBGI commissioningPLL setting-upCurrent Status of Abort Gap MonitorHigh Intensity BI LHC Commissioning Beam Commissioning Working Group 15th June 2010 Rhodri Jones
BPMs work on bunch to bunch basisOnly depend on bunch intensityBPMs can be used in 2 sensitivity modesHigh sensitivityFrom ~ 1109 to ~51010Low sensitivityFrom ~ 51010 to ~21011Only changes threshold for bunch detectionNo gains changedRequired to make system immune from reflections generated by imperfect cabling, connections & BPMs.1st MD showed thatB2 behaved as expectedB1 had a grey zone between 31010 and 51010 where neither sensitivity gave required resultsDependence of BPM Readings on Bunch Intensity Beam Commissioning Working Group 15th June 2010 Rhodri Jones
One nominal bunch of 11011 slowly scraped away using a primary collimatorSensitivity constantly changed from high to lowOutliers due to acquisition overlapping two sensitivity rangesSensitivity ranges seen to overlap as expected at around 51010BPM Dependence on Intensity - Beam 2 Beam Commissioning Working Group 15th June 2010 Rhodri Jones
One nominal bunch of 11011 slowly scraped away using a primary collimator2 fills one for low sensitivity and one for high sensitivityBPM Dependence on Intensity - Beam 1 Beam Commissioning Working Group 15th June 2010 Rhodri Jones
Low SensitivityHigh SensitivityDead zone where neither setting works well0 2 4 6 8 10 1210100 2 4 6 8 10 121010B1 Arc BPM variation - 51010 to 11011 Beam Commissioning Working Group 15th June 2010 Rhodri Jones
Mean = 55mmStdev = 80mmMean = 53mmStdev = 76mm
B1 Arc BPM variation - 61010 to 11011 Beam Commissioning Working Group 15th June 2010 Rhodri Jones
Mean = 11mmStdev = 50mmMean = 8mmStdev = 44mm
B1 LSS BPM variation - 61010 to 11011 Beam Commissioning Working Group 15th June 2010 Rhodri Jones
Mean = 20mmStdev = 57mmMean = 15mmStdev = 74mmB1 v B2 Comparison - 61010 to 11011 Beam Commissioning Working Group 15th June 2010 Rhodri Jones
Mean = 8mmStdev = 44mm
Mean = 15mmStdev = 74mmArc BPMsLSS BPMs
Mean = 21mmStdev = 60mm
Mean = 2mmStdev = 48mm9BPM SystemMax variation with intensity