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The data taken during experiments E385 and E387, after being stored on 8mm magnetic data tapes, were processed offline using computer facilities at The Ohio State University. This ``replay'' consisted of essentially two parts: 1) The data were replayed in several passes using XSYS (mentioned at the end of Chapter gif) to calibrate the necessary software offsets and finally produce a useful reduced data set; and 2) That reduced data set was analyzed using PAW (after conversion of the data to the ntuples used in PAW) to apply the final cuts and obtain the appropriately gated spectra for further analysis. This separation of reduction tasks has the advantage of being able to perform the bulk of the replay without concern for the final cuts. Then it is possible to experiment with the final cuts in the later part of the replay without experiencing the significant time penalty of re-analyzing the entire raw data set. This became especially important in this experiment because the experiment was performed so soon after the new INPOL facility was built that the cuts associated with optimal efficiency had not been determined when this analysis was started. In fact, at this time, those cuts are still not a settled issue, so it is necessary to have the reduced data set, which can be replayed in a timely fashion, to keep up with changes in the characterization of the detector. The detector characterization will be discussed later in this chapter.

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