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How do I make a Deep Survey Light-curve ?

Data after 18 Nov 1993 was pointed 1 arcmin from the deadspot, but one should check any data taken during or before 1994. You can over-plot the DS dead spot pixel mask ( and compare. How to make a dead spot time filter is explained in the old DS light curve notes.

 Use the XRAY.XTIMING package. 

 First thing is to make the DS QPOE PROS compatible by adding the
 time filter as a deffilt:

epar qphedit 

         qpoe = "ds.qp"         qpoe(s) to be edited
       fields = "deffilt"       fields to be edited
        value = "time=(ds_gt)"  value expression
         (add = yes)            add rather than edit fields
      (delete = no)             delete rather than edit fields
      (verify = yes)            verify each edit operation
        (show = yes)            print record of each edit operation
      (update = yes)            enable updating of the image header
        (mode = "al")           

Examine the ds.qp file with Saoimage or Ximtool and determine
appropriate source and background apertures. 

Then run timsort:

        image = "ds.qp"         input qpoe file name
     soutfile = "ds"            Output time-ordered file name
      sregion = "c 1021.75 1025.25 16.5" source region descriptor
     boutfile = "lex"           Output time-ordered bkgd file name
      bregion = "a 1021.75 1025.25 30.5 100.5" background region descriptor
         (exp = "NONE")         exposure mask
     (ethresh = 0.)             min. percent of exp time for inclusion
       (esize = "region")       QPOE event size
     (clobber = yes)            OK to delete existing output file?
     (display = 0)              0=no disp, 1=header
       (ssize = 10000000)       max number of events per sort
         (qpi = yes)            prompt for qp internals?
       (psize = 4096)           page size for qpoe file
       (bsize = 8192)           bucket length of qpoe file
       (debug = 0)              qpoe debug level
        (mode = "al")           

Running ltcurv to crate an EUVE light curve with one bin per
EUVE orbit.

  source_file = "ds_sti"       Input Source Timing File
 background_f = "lex_bti"       Input Background Timing File
  ltcurv_file = "my_ds_lc"         root name for output file []
         bins = INDEF           Number of Bins (0 for bin length)
   bin_length = 5690.            Bin Length in Secs
     (display = 1)              Display Level
     (clobber = yes)            clobber
  (get_gintvs = yes)            get good intvs from qpoe hdr
(bk_norm_fact = 1.)             Bkgd normalization factor
        (mode = "al")    

you can then plot it with ltcplot using ctrt and err as the 
column and ecolumn names, however you should correct the count 
rates for primbsching, deadtime and vignetting using the 
euv.euvred.effexp package (see below).
        table = "my_ds_lc"         Input Table File
       outplt =                 Plot output file
      (column = "corr_rate")         Plot data column name
   (plot_type = "bar")          Plot type - histo|bar
     (ecolumn = "corr_err")          Error column name
  (plot_title = "Light Curve :") Plot Title
     (x_title = "Time (seconds)") Plot Title
     (y_title = "Count Rate (cts/sec)") Plot Title
      (hdcopy = no)             Output to Printer?
      (gclose = no)             Close Graph window after plot?
   (num_plots = 1)              number of plots
     (x_units = "seconds")      X axis units - seconds | col name
      (x_tics = 6.)             num x labels
      (y_tics = 6.)             num y labels
  (label_size = 0.75)           labels format
 (tlabel_size = 0.5)            tic labels format
     (x_range = "auto")         x_range - auto|input limits
     (y_range = "auto")      y_range - auto|input limits
     (clobber = no)             Overwrite existing plot?
      (cursor = "")             Graphics cursor input
        (mode = "ql")           

 However, the new archive format data effexp looks like:

     intervals = ""    QPOE file or ST table specifying valid interval
       (stime = "stime")        Column in input table for start times
       (etime = "etime")        Column in input table for end times
      (ltcurv = "my_ds_lc_ltc") Light curve table
          (t0 = INDEF)          Start time of integration
          (t1 = INDEF)          End time of integration
        (mask = "")             Pixel list with region mask
    (primbsch = "[quadrant]") Primbsch table
    (ptimecol = "TIME")         Column in primbsch table for times
     (usedead = yes)            Include deadtime correction?
     (useprim = yes)            Include primbsch correction?
    (quadrant = 1)              Quadrant to use for all times
      (detpos = "detposds")     Detector position table
    (dtimecol = "TableTime")    Column in detpos table for times
       (dxcol = "UDX")          Column in detpos table for x position
       (dycol = "UDY")          Column in detpos table for y position
(usevignettin = yes)             Include vignetting correction?
   (undistort = yes)             Undistort before vignetting correction?
     (refdata = "reference/") Name of ST table for reference data
    (detector = "ds")           Detector name 
  (filtertype = "lex")          Type of filter [lex|alc|dag|tin]
      (sublen = 0.1)            Subinterval length
    (exposure = INDEF         ) Effective exposure
 (rawexposure = INDEF         ) Raw exposure
     (verbose = yes)            Print exposure on STDOUT?
        (mode = "al")  

and the new format for detpos (if you need it):
        input = "[orientation]" Name of input aspect ST table
       output = "detpos"        Prefix for output aspect ST tables
     (refdata = "reference/") Name of ST table for reference data
   (detectors = "ds")           Detector list [sca|scb|scc|ds]
          (ra = RA_OBJ)       Source right ascension
         (dec = DEC_OBJ)        Source declination in decimal degrees
     (raunits = "degrees")      Units of RA [degrees|hours]
        (time = "time")         Time column of input aspect table
     (aspectw = "aspectw")      Aspect W input column name
     (aspectx = "aspectx")      Aspect X input column name
     (aspecty = "aspecty")      Aspect Y input column name
     (aspectz = "aspectz")      Aspect Z input column name
        (mode = "al")