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A Quick Look at Spectral Fitting

This section describes a short procedure for finding the best fit parameters of a chosen model and the flux and luminosity of a source.

xs> qpspec xdata$rp110590 ``c(6930,9390,240)'' xdata$rp110590 ``a(6930,9390,300,600)''
          # extract the source counts from a 2' circle centered on the target and
      # the background counts from an annulus between 2.5' and 5' from the source

xs> dofitplot rp90 ``abs(20:22)*pow(0:3)'' print_table=yes   print_plot=yes 
        # This command fits an absorbed power-law model to the data, brings up a
              # plot of the predicted and observed pulse height distribution and
           # generates hardcopies of both the plot and the table of observed and
                                                             # predicted counts.

xs> xflux fluxin=rp90 energy=``0.1:2.4'' dis=``1.0k''  # Calculate the integrated
   # flux betwen 0.1 and 2.4 keV and the luminosity using a distance of 1.0 kpc.