ii_spectra_extract

ii_spectra_extract reads the shadowgram for each input energy band.

For each output energy band, it :

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creates a model (PIF) for each source. The Pixel Illumination Factor (PIF) is a number between 0 and 1, which expresses the theoretical degree of illumination of each pixel in the detector plane of a coded-mask instrument. The PIF is calculated on the basis of the position and is normalized to 1 cts/pix source.

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fits all source intensities together with a background estimate to the data (shadowgrams)

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writes all source estimates to the spectra index

Finally, ii_spectra_extract writes to the PIF index one mean model per input catalogue source.

There is a possibility to chose one of several fitting metods. The recommended method is iterative imaging-like Least Squares fit (method 6). In the first step of this method the fit of each source separately in its coded zone is done. Next, in the second step, the calculation of reciprocal source contributions is performed. The first step is aimed to decrease the background modelling error influence. The second one, corresponds to the ghost cleaning. Please note that Maximum Likelihood method is not working in standard OSA configuration (with isdcmath package).

In the fitting process the source positions are considered to be exact. If the input background map is given , then the background map fitting is performed.

Table 23: ii_spectra_extract parameters included into the main script.

Name	Name	Type	Description
(in the main script)	(executable)
SCW2_ISPE_idx_isgrResp	idx_isgrResp	string	DOL of the index of ISGRI response matrices default: ``''
SCW2_ISPE_DataMode	DataMode	integer	Data Simulation mode possible values: 0 real data 1 simulated data default: 0
SCW2_ISPE_MethodInt	MethodInt	integer	Method to be applied for the pixel value interpolation default: 1
SCW2_ISPE_MethodFit	MethodFit	integer	Method to be applied for background and source intensity fitting possible values: MethodFit = 0 == CHI2 MethodFit = 1 == Maximum Likelihood MethodFit = 2 == Least Squares MethodFit = 6 == iterative imaging-like Least Squares fit default: 6
SCW2_ISPE_isgrUnifDol	isgrUnifDol	string	DOL of the ISGRI detector uniformity default: ``''
SCW2_ISPE_isgrBkgDol	isgrBkgDol	string	DOL of the ISGRI background model default: ``''
tungAtt	tungAtt	string	DOL of the Tungsten attenuation length fits file default: ``''
aluAtt	aluAtt	string	DOL of the Aluminium attenuation length fits file default: ``''
leadAtt	leadAtt	string	DOL of the Lead attenuation length fits file default: `` ''
rebinned_corrDol_spe	corrDol	string	DOL of the rebinned ISGRI off-axis corrections for spectrum default: `` ''