HV and Threshold calibration
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Revision as of 07:49, 13 April 2010 by Rshneor (Talk | contribs) (New page: Procedure for the neutron array HV and threshold calibration Main considerations - * calibrate all neutron bars to equal gains. * set threshold voltage as low as posibble (50 mV), to re...)
Procedure for the neutron array HV and threshold calibration
Main considerations -
- calibrate all neutron bars to equal gains.
- set threshold voltage as low as posibble (50 mV), to reduce current on PMT's.
- set threshold energy as low as possible to increase efficiency.
- set threshold energy low enough to be able to separate minimum ionizing electrons.
(optimum was chosen at around 5 MeV)
We will use the following know energy point for the calibration
Calibrations steps -
- test-area calibration using cosmic muons
Use top-buttom bar trigger, to obtain vertically going minimum ionizing muons with know energy deposit.
calibrate the muon peak to be at- 10.0 cm bar -> E=20 MeV -> channel=1500 12.5 cm bar -> E=25 MeV -> channel=1875 15.0 cm bar -> E=30 MeV -> channel=2250 25.0 cm bar -> E=50 MeV -> channel=3750
