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Flux Calibration

Parameters for instrumental response estimation and flux calibration are displayed by the command:

Midas...> SHOW/LONG f

The flux calibration consists of correcting for atmospheric extinction using a table \fbox{EXTAB} and of comparing the one-dimensional reduced spectrum of a standard star \fbox{STD} to a reference flux table \fbox{FLUXTAB}. The sequence:

Midas...> SET/LONG FLUXTAB=fei110 EXTAB=atmoexan
Midas...> PLOT/FLUX
Midas...> EXTINCTION/LONG std23 ex23

plots the flux table and corects the one-dimensional reduced spectrum std23 for the atmospheric extinction. The instrumental response can be estimated by filtering with the command:

Midas...> RESPONSE/FILTER ex23
Midas...> PLOT/RESPONSE

or by polynomial or spline interpolation using the sequence:

Midas...> INTEGRATE/LONG ex23
Midas...> RESPONSE/LONG fit=SPLINE
Midas...> PLOT/RESPONSE

The obtained response is stored in the image response.bdf and can be applied to any reduced, extinction corrected spectrum using the command:

Midas...> CALIBRATE/FLUX exspec spectrum



Petra Nass
1999-06-15