Calibration Access and Data Handbook

next up previous contents
Next: HKPARMINT Up: Generation from In-Orbit Data Previous: Wavelength calibration   Contents

Flux calibration

Spectroscopic Standard stars, mainly white dwarfs, were observed with both OM grisms. The ISF is obtained by dividing the extracted spectrum, in count rate versus wavelength, by the standard flux of the star obtained from HST Calspec database. The results obtained from several stars are then averaged and the standard deviation is taken as the error in the ISF.

Due to the presence on spectral lines, mainly in the Visible grism, the spectra of the standard stars are interpolated and re-sampled prior to the division.

The first ISF's have been obtained from several observations with OM of the selected stars. Two of them have been included in the XMM-Newton Routine Calibration Plan, to be observed periodically to study variations with time which will be incorporated into the flux calibration.

Michael Smith 2011-09-20