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ii_spectra_extract

ii_spectra_extract reads the shadowgram for each input energy band.

For each output energy band, it :

-
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.

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

-
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: `` ''


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Next: ip_spectra_extract Up: Spectral Analysis Previous: Spectral Analysis   Contents
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