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Next: Pulse Height Gains Up: DATA REDUCTION Previous: Replay



As was mentioned above, the cosmic rays are used to calibrate the detector on a continual basis. This means that while the detector is gathering data on neutron polarization it is also gathering calibration data. Offline the calibration data are used to recalibrate the software offsets for each individual run (one run = hours of data-taking) before other quantities are extracted to insure that the data remain accurate. There are five different calibrations performed on the data for each run: pulse height gains, position time offsets in each cell, relative time offsets between cells in a plane, relative timing offsets between the planes, and overall timing offset for the detector. Each of these will be described below.

Michael A. Lisa
Tue Apr 1 08:52:10 EST 1997