addascaspec -- add ASCA spectra


          addascaspec [-qh] list_file out_spec out_response [outbgd] [errmeth]


addascaspec is a perl script used to combine ASCA spectra taken by SIS0 and SIS1 or GIS2 and GIS3. It can also be used to add spectra taken at different times.

The following ftools are invoked; fparkey, fkeypar, mathpha, addarf, addrmf, marfrmf, and pget.

Note that addascaspec is more specialized than the similarly-named HEASARC task addspec. addascaspec was specifically written for the case of simultaneous observations by two essentially identical telescopes. For example, addascaspec would be appropriate for co-adding NuSTAR FPMA and FPMB for the same observation, whereas addspec is more appropriate for adding data from the same detector at different times.



     -h   Print this help message.
     -q   Display commands to spawn, but does not execute them.

The 'list_file' should have the following format:

       g2_source.spec g3_source.spec 
       g2_bgd.spec g3_bgd.spec  
       g2.arf g3.arf

On each line, list the spectra, background, arf, and rmf file names to combine. You can add two or more spectral files. Order of the appearance of lines does not matter, but source spectral files should appear prior to the background files. You may or may not enter background files and rmf files to combine.

Note that in the case of GIS, you do not have to add RMFs, since GIS2 and 3 RMFs are identical. In this case only ARFs are averaged. For SIS, each ARF and RMF are multiplied and averaged.

Note that filenames containing the reserved arithmetical symbols for addition ("+"), subtraction ("-"), or multiplication ("*") - or containing parentheses ("(" or ")") - will likely be misinterpreted by mathpha as operators and cause the task to fail.

The optional "errmeth" parameter specifies the error method passed to the "mathpha" task. If not specified, the default option used is "Poiss-0".

If "Gauss" or "Poiss-0", poisson error is assumed after counts are summed.

The method of calculation is explained in the ASCA ABC guide ( section 8.9. The background normalization is calculated with the formula explained at


Jan96 ftools.asca