E852 Detectors: Beam Hodoscopes

E852 Detectors: Beam Hodoscopes


Introduction

The MPS A1-line Beam hodoscopes are instrumented with LeCroy 1876 TDCs, which have a 1 ns time resolution.

How To Set the Beam Hodoscopes TDC Time Window

  1. obtain an analyzed data file with at least 500 events
  2. extract the TDC information from the data by running the 'viewBeamHodoTdc' program:
    	> ~olchansk/e852/A/viewBeamHodoTdc < file.dat > file.view
    	
  3. calculate the time window by running the 'makeBeamHodoTdcTiming.perl' program:
    	> ~olchansk/e852/A/makeBeamHodoTdcTiming.perl < file.view
    	
    It's typical output is:
    	Plane:  3 (AX311),   count:  4216, average:  -1052 maxbin: 138, count:  149, mode: 139, sigma:  5.40, min: 133, max: 147, 34-43-30-149-105-3-3-3
    	Plane:  6 (AX312),   count:  2296, average:   -957 maxbin: 136, count:  169, mode: 136, sigma:  2.85, min: 127, max: 141, 3-25-101-169-32-3-1-
    	Plane:  9 (AX321),   count:  2166, average:   -948 maxbin: 136, count:  146, mode: 136, sigma:  2.23, min: 127, max: 141, 4-30-113-146-39-24-1-1
    	Plane: 12 (AX322),   count:  2716, average:   -970 maxbin: 172, count:  135, mode: 171, sigma:  2.48, min: 163, max: 177, 7-33-118-135-28---1
    	Plane: 17 (AX331),   count:  4152, average:   -995 maxbin: 212, count:  186, mode: 212, sigma:  4.21, min: 207, max: 221, 10-19-44-186-124-6--
    	Plane: 18 (AY331),   count:  2813, average:  -1013 maxbin: 212, count:  196, mode: 212, sigma:  1.93, min: 203, max: 217, 2-17-117-196-32-1--1
    	Plane: 23 (AX332),   count:  4002, average:  -1087 maxbin: 198, count:  244, mode: 198, sigma:  3.54, min: 193, max: 203, 4-7-66-244-54-3--
    	Plane: 24 (AY332),   count:  1909, average:   -944 maxbin: 194, count:  177, mode: 194, sigma:  1.52, min: 189, max: 203, -6-67-177-98-4--
    	space.beamhodoscope.AX311.tdc_min: 133
    	space.beamhodoscope.AX311.tdc_max: 147
    	space.beamhodoscope.AX312.tdc_min: 127
    	space.beamhodoscope.AX312.tdc_max: 141
    	space.beamhodoscope.AX321.tdc_min: 127
    	space.beamhodoscope.AX321.tdc_max: 141
    	space.beamhodoscope.AX322.tdc_min: 163
    	space.beamhodoscope.AX322.tdc_max: 177
    	space.beamhodoscope.AX331.tdc_min: 207
    	space.beamhodoscope.AX331.tdc_max: 221
    	space.beamhodoscope.AY331.tdc_min: 203
    	space.beamhodoscope.AY331.tdc_max: 217
    	space.beamhodoscope.AX332.tdc_min: 193
    	space.beamhodoscope.AX332.tdc_max: 203
    	space.beamhodoscope.AY332.tdc_min: 189
    	space.beamhodoscope.AY332.tdc_max: 203
    	
  4. Grab the 'space.beamhodoscope.xxxx' lines and shove them into the map manager, file db-files.Map, subsystem db-files, item param.beamhodo, with an appropriate run number. One way to do it is to cut and paste these lines into the xmapbrowser program.

Typical Beam Hodoscope Profiles

The beam profiles were taken using the beamtune program on live data from run 9090 and the GIF pictures were made using xv

H1 and H2

H3 and H4

H5 X and Y

H6 X and Y

Typical Beam Hodoscope TDC Distribution

//CO 18-Jan-1995