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Flux Calibration

The commands EXTINCT/LONG followed by RESPONSE/FILTER or by INTEGRATE/LONG and RESPONSE/LONG permit a one-dimensional response curve response.bdf to be obtained from the extracted (e.g., via EXTRACT/LONG or EXTRACT/AVERAGE) and wavelength calibrated spectrum of a standard star.

The command RESPONSE/FILTER divides the standard star spectrum by the flux table values and uses median and smooth filterings (parameters FILTMED and FILTSMO) to smooth the instrumental response function.

The command INTEGRATE/LONG also performs a division of the standard star spectrum by the flux table but generates an table of response values at a wavelength step equal to the one of the flux table. The command RESPONSE/LONG interpolates these values using a polynomial or spline interpolation scheme.

This response curve can be applied to a one- or two-dimensional extracted, wavelength calibrated and extinction corrected (EXTINCTION/LONG) spectrum by the command CALIBRATE/FLUX.

Verification commands include PLOT/FLUX to visualize the standard star reference flux table and PLOT/RESPONSE to vizualize the final instrumental response  function.


Petra Nass