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: http://xmm.vilspa.esa.es/sas/8.0.0/doc/rgscombine/node5.html
Дата изменения: Wed Oct 22 18:09:44 2008 Дата индексирования: Fri Oct 16 22:20:47 2009 Кодировка: Поисковые слова: arp 220 |
This task adds spectra, background spectra and response matrices of the same instrument and spectral order (beta binning) or both instruments and same spectral order (wavelength bining), to produce combined files that can be used for quantitative analysis in a spectral fitting package such as Xspec. The component spectra should have been produced by rgsproc, using the spectrumbinning parameter set to lambda, if you would like to combine RGS1 and RGS2 spectra. Or, if you are using the spectrumbinning parameter set to beta, then the component spectra should have been produced by rgsproc, using the attsyle=user parameters so that all spectra and responses are aligned in wavelength. For example, and for each observation of the set, the call to rgsproc could be:
rgsproc withsrc=yes srclabel=Capella srcstyle=radec srcra=79.172330 srcdec=+45.997991 attstyle=user attra=79.172330 attdec=+45.997991 attapos=259.81
Right ascension and declination are the object coordinates and are used twice for the parameters srcra and srcdec, and also attra and attdec. The position angle is a feature of an individual obersvation and can be found in the POS details for each observation in XMM-Newton archive, XSA, or in the Observation Log Browser on the XMM-Newton website.
The task differs from rgsfluxer, in that it is able to combine response matrices and produce a single response matrix for spectral analysis. The spectra attributes and response values, bar counts, are weighted prior to addition, in terms of the exposure time and areascal of the individual observation. In this way the spectra (NET or TOTAL), including background spectra, can be combined.