In order to generate degap coefficients, a projection of an HRC (-I or -S) flat-field is needed. The projection file can be created with "epr2prj" (executable v1.0, source text v1.0). With the projection file as input, the tool "mkdegap" (executable v1.0, source text v1.0) can then be used to calculate the degap coefficients. It does so by making a linear or quadratic fit(user selectable) across the gaps seen in the projection file.

Once a table of degap coefficients (the output of "mkdegap") has been generated, they can be applied to a photon event record to correct the data and "degap" the image. The tool "epr2epr" (executable v1.0, source text v1.0) requires as input the event list to be processed and the table of degap coefficients, and it outputs a position-corrected event list.

By running an executable with the flag "-h" (for example, "mkdegap -h"), the program usage/help is displayed.

Last modified: 09/25/12

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