.help osorat Aug 99 ftools.oso8 
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NAME
osorat -- Extract lightcurves from the OSO8 raw rate data 
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USAGE
osorat equinox ra dec detector filelist outfile 
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DESCRIPTION

 This task extracts background subtracted and collimator corrected lightcurves 
 from the OSO8 raw rate data obtained with the CGXSE experiment for a given 
 sky position. The CGXSE on board OSO8 consisted of three proportional
 counters (2 xenon,  1 argon). Two detectors (B and C) had fields of
 view aligned with the spin axis in opposite directions. The third,
 detector A, is offset 5 degrees from the spin axis and is located on
 the same side as the B detector. The fields of view (FOV) were 5, 3 and 5
 degrees for the detectors A, B and C respectively. The B and C were
 pointed  detectors, instead A was a scanning detector.  
 The program uses as input the OSO8 raw rate data files as stored in
 the HEASARC archive. Each file contains one day of data for the A, B
 and C detectors. To select the OSO8 raw rate data file which most
 likely includes a given sky position in the detector FOVs, users should
 run first the script 'osofindfast'. This determines which detector
 viewed a particular position throughout the entire OSO8 mission and  
 outputs a file list of filenames, one for each detector, as input for
 'osorat'.  

 Only lightcurves for one detector (A, B or C) can be extracted during 
 each run of 'osorat'. For a given detector multiple lightcurves are output 
 if a source position was observed several times during the OSO8 mission at
 intervals greater than a week. The output lightcurve excludes data
 detected below a default detector collimator response. These limits
 are set in the parameters  'arlima', 'arlimb' and 'arlimc' for the A,
 B and C detectors respectively in unit of cm**2.  Data are also
 excluded if an overflow is detected in the telemetry stream.  
 The default setting excludes telemetry records (~66 points of 160 ms
 each ) if an overflow occurs in any of the detectors. Less restrictive
 data filtering is allowed by changing the parameter 'filter'.  The
 background levels (and errors) are set to fixed values, different for
 each of the detectors, corresponding to the nominal detectors plus sky
 as best known. These values can be altered using the appropriate
 parameters relative to each of the detectors. 
 The time resolution of the output lightcurves is 0.16 seconds. For
 the detector A the program currently does not account for confusing
 sources included in the A detector FOV during a spin revolution (~10
 seconds), therefore it should be used with caution. 

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PARAMETERS
.ls equinox [real]
 Equinox of the input sky position (default value 1950)
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.ls ra [string]
 The Right Ascension given in hh mm ss.s or degrees.
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.ls dec [string]
 The Declination given in dd mm ss.s or degrees.
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.ls detector [integer]
 Detector number. The program extracts lightcurves for only the 
 one detector specified in this parameter. The parameter values are 
 1, 2 and 3 for the detector A, B and C respectively.
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.ls filelist [string]
 The name of the file containing the list of raw rates files 
 (listed as one filename per line). The file list can be created
 using the script 'osofindfast'. 
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.ls outfile [string]
 The root name for the output lightcurves. The program will output multiple 
 lightcurves if there is an interval greater than a week between
 observations of the source position. The lightcurves are named by
 adding a sequential number to the 'outfile' parameter starting from 1. 
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.ls (binspin) [boolean]
 Logical flag to indicate whether the user wishes the data to be
 binned once per spin revolution. By default this parameter is 'no'
 and the data are binned at 0.16 seconds. By setting this parameter to
 'yes' the data are binned at once per spin revolution, which
 corresponds to about 10 seconds.   
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.ls (arlima=10.0) [real]
 Only data above the detector area limit set by this parameter are included 
 in the output lightcurves. The area of the A detector is 263 cm**2
 and the area limit is currently set to 10 cm**2.
 
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.ls (arlimb=5.0) [real]
 Only data above the detector area limit set by this parameter are included 
 in the output lightcurves. The area of the B detector is 76 cm**2
 and the area limit is currently set to 5 cm**2.
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.ls (arlimc=50.0) [real]
 Only data above the detector area limit set by this parameter are included 
 in the output lightcurves. The area of the C detector is 237 cm**2
 and the area limit is currently set to 50 cm**2.
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.ls (abkg=3.4) [real]
   Background value for the A detector given as count per 0.160 seconds.
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.ls (bbkg=0.16) [real]
   Background value for the B detector given as count per 0.160 seconds.
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.ls (cbkg=1.6) [real]
   Background value for the C detector given as count per 0.160 seconds.
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.ls (abkgerr=0.12) [real]
   Background error for the A detector for 0.160 seconds integration time.
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.ls (bbkgerr=0.008) [real]
   Background error for the B detector for 0.160 seconds integration time.
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.ls (cbkgerr=0.08) [real]
   Background error for the C detector for 0.160 seconds integration time.
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.ls (filter=1) [integer]
   Set filtering due to data overflows. The values range between 1-4 with the 
   following meaning. Filter value=1 (default), skip an entire record
   of data if an overflow is detected for that record in any of the
   detectors. Filter value=2, skip only one data point if overflow is
   for that data point in any of the detectors. 
   Filter values 3 and 4 skip either a record or a point if overflow
   occurs in the detector for which the lightcurve is extracted. 
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. endhelp
