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Extracting the lightcurve

You can extract the lightcurve from an IDF file with ttag_lightcurve.

Usage:
  ttag_lightcurve [-hf] [-v level] input_file output_file windows_file
                                  bins LiForSiC

Arguments:
  input_file     : ttag IDF file

  output_file    : ASCII file with 2 columns:
                        - time (MJD)
                        - countrate corrected for deadtime

  windows_file   : input ASCII file with 2 columns :
                        - start of spectral windows
                        - stop of spectral windows

  bins           : bin size in seconds
  LiForSiC       : 1=LiF, 2=SiC

Options:
  -h:  this help message                 
  -f:  output calibrated flux (erg/cm2/s) instead of countrate  
  -v:  verbosity level (=1; 0 is silent)

All photons that are not in the selected channel, that are not in the spectral windows (defined in the spectral windows file), that have LOCATION_FLAGS not equal to zero or that are not in the good times are not selected. Thus the lightcurve extraction result depends on the way you screened the IDF file.

The f switch makes the program output the calibrated flux instead of the countrate. Note that no background substraction is performed.

The output lightcurve is not defined outside the good time intervals. The output ASCII file is tagged with the Geocentric Modified Julian Day. To convert the time-tag from Geocentric to Heliocentric in the whole file, use ttag_lightcurve_mjd2hmjd:

Usage:
  ttag_lightcurve_mjd2hmjd [-h] [-v level] output_file input_file
                                   hh mm ss dd mm ss

Arguments:
  input_file     : ASCII file with 2 columns :
                     - time (MJD) 
                     - signal

  output_file    : ASCII file with 2 columns : 
                     - time (HMJD) 
                     - signal 

  hh mm ss dd mm ss : RA and DEC of target

Options:
  -h:  this help message                 
  -v:  verbosity level (=1; 0 is silent)



Bernard Godard 2004-11-04