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LTE

Purpose: Evaluate the polynomial fit by RATE_FIT to determine the number of counts (if any) to attribute to the long-term enhancement. LTE does the following: 1) integrates the fitted polynomial to find the total number of cosmic background plus LTE counts in the observation, 2) finds the minimum in the fitted polynomial, and 3) finds the number of counts in the fitted polynomial in the excess over the minimum value. This excess is interpreted as the minimum value for the LTE contribution to the image and will be subtracted from the image.

File Input:
1) Observation data set fits files - xxx_EVENTRATES.FITS for German or US data, xxx_ANC.FITS for RDF data.
2) Other fixed input - valid_times.dat. This is a file containing a modified version of valid_times_all.dat, the output of program VALID_TIMES. The user can apply additional time-selection criteria such as the exclusion of intense periods of scattered solar X-ray or auroral contamination. This must be the same time selection as used with the programs CAST_DATA, CAST_EXP, CAST_PART, and TILT.

Interactive Input:
1) Observation control - the eight or fewer character string listed above as xxx.
2) Data format control - 1 for German data, 2 for US data, 3 for RDF data.
3) Time offset and polynomial coefficients - The values of T0 and I0-I4 listed in the output of program RATE_FIT.

Screen Output:
Exposure time, total counts, and net counts. The value net counts is used in the program CAST_SSX as the long-term enhancement counts for casting into sky coordinates. The value total counts is the integral of the polynomial fit to the light curve, not the total number of observed counts. It does not include particle background or scattered solar X-ray counts.