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Astron. Astrophys. 349, L49-L52 (1999) 3. Observations and data analysisOur results were obtained with the Medium Energy Concentrator
Spectrometer (MECS, Boella et al. 1997) that provides images in the
For the spectral analysis we have used the MECS effective area values appropriate for extended sources. These were properly derived by convolving a flat surface brightness distribution with the energy and position dependent vignetting and Point Spread Function (PSF). All the spectra have been corrected for the the instrumental
background by subtracting a spectrum obtained from MECS observations
of the dark Earth. This procedure does not account for the subtraction
of the cosmic X-ray background (CXB). Indeed, the subtraction of the
MECS standard background obtained from high galactic latitude
pointings would overestimate the CXB contribution, which is highly
absorbed in the GC region. The CXB contribution has been included as a
known additive component in the spectral fits with an absorbing column
density of 8 ![]() ![]() ![]() ![]() © European Southern Observatory (ESO) 1999 Online publication: September 2, 1999 ![]() |