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Further reductions: averages, nightly means, and normal points

The programme kokpol can compute average values for a number of stars, the nightly mean values for stars, normal points, and can do phase corrections for stars that vary periodically.

The programme needs a file, say, star.sta with the numbers of the stars for which averages have to be computed. In addition, the epoch of zero phase (last 4 digits of the Julian day number), period (in days), coordinates ( and in decimal form) for the calculation of the heliocentric correction to the normal points. If data is not relevant, put zeroes in the file.

kokpol prompts for filenames, and (in a self explanatory way) asks what kind of averaging procedure has to be applied. The output file from polred is the input file for kokpol. The output files plotfin.sa for plotting the nightly means and plotfil.sa for the normal points are shown. if asked for. The user specified output file contains the results in tabular form for printing.

Note that if there is more than one input file, the programme pickup has to be run first to collect into one file all the stars that have been specified in the star.sta file. The copy command under DOS can also be used to do this.

The averaging procedure weights the observations with the inverse square of the errors, taking the larger of E and E, making sure that the weights never exceed the theoretical maximum given by simple photon shot noise.



Lars Freyhammer
Wed Oct 27 18:02:24 ACT 1999