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Institut für Astronomie und AstrophysikAbteilung AstronomieSand 1, D-72076 Tübingen, Germany |
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writelc
Write an OGIP-compliant FITS lightcurve, conforming
(hopefully) to
http://heasarc.gsfc.nasa.gov/docs/heasarc/ofwg/docs/rates/ogip_93_003/ogip_93_003.html
with later extensions
High-energy astrophysics
writelc,time,rate,error,lcfile
or
writelc,time,rate,lcfile
time : Time (LEADING EDGE OF BIN!!!!)
rate : Countrate (cps) or number of counts (counts/bin)
(depending on /counts keyword)
measured from time[i]..time[i+1]
error : if given, uncertainty of rate (same units as rate)
lcfile : name of the lightcurve to be written
barytime : Write a bary center corrected time column. Also the
TIMEREF keyword is set at 'LOCAL', i.e. the
time column remains untouched.
No BSTART/BSTOP/BZERO parameters are added.
The column type is set at BARYCENTER (not
following the OGIP recomendation but the result
of fxbary).
telescope : ID of telescope (default: unknown)
instrument: ID of instrument
object : name of observed object
pos_ra,pos_dec: position of observed object (degrees!), implies:
equinox : equinox os coordinate
radecsys : coordinate-frame used
date_obs : start-time string (dd/mm/yy), UTC, implies
time_obs : start-time (hh:mm:ss), UTC
date_end : end-time (dd/mm/yy), UTC
time_end : end-time (hh:mm:ss), UTC
jdobs : Julian Date of start of observation, implies
jdend : JD of end of observation
filter : filter used (default: none)
counts : if set, "rate" contains number of events per time bin
(default: rate is counting rate (events/s))
second : if set, all times are in seconds
(time col, tstart, tstop)
day : if set, all times are in days (time col, tstart, tstop)
mjdrefi/mjdreff: integer and real part of base MJD of lightcurve
mjdref0 : base MJD of lightcurve
tstarti,tstartf,tstart0: start time of lc
(either integer/real, or total)
tstopi,tstopf,tstop0: stop time of lc (either integer/real, or
total)
sysjd,sysmjd,systjd: set ONE of these to define the timesystem
utc : if set, time system is UTC
ontime : total time the source was observed, IN SECONDS
backsub : lightcurve is background-subtracted
deadcorr : rates are deadtime-corrected
a file gets written
Compared to the OGIP memo, the following restrictions apply:
note: we always write the time into the file, even for equally
spaced lcs
Information on barycentric correction (TIMEREF keyword and
associated info), who assigned the time (TASSIGN), and timing
uncertainty is not yet written.
lightcurves for multiple energy bands in the same lc cannot be
written.
information on vignetting is not written.
background values are not written (BACKV columns)
deadtime information is not written in extra column (DEADC column)
event list info is not written (EVENT extension)
additionally possible extensions (barycentric correction, gti,...)
is not written
Version 1.1: 2001/03/22 Joern Wilms
... Version 1.3: 2001/03/22 JW: further improvements and
bugfixes
... Version 1.4: 2002/01/14 JW: renamed ra and dec keywords
into pos_ra and pos_dec to avoid IDL keyword clash with
radecsys keyword
$Log: writelc.pro,v $
Revision 1.5 2003/04/03 16:14:40 goehler
added optional bary input for bary center corrected time columns.
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