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Last modified: 22 Dec 2014

URL: http://cxc.harvard.edu/ciao/threads/spectra_multi_acis/

Grating Spectra for Multiple Sources - ACIS

CIAO 4.9 Science Threads


Overview

Synopsis:

Generate a PHA2 spectrum file for an ACIS-S grating observation with multiple sources in the field of view.

Run this thread if:

you are working with an ACIS HETG or LETG dataset and wish to create spectra for each of the sources in the field of view. Since multiple-source analysis is not done in standard processing, all users interested in more than one source in the field need to complete this thread.

Related Links:

Last Update: 22 Dec 2014 - Reviewed fro CIAO 4.7; minor edits only.


Contents


Data Preparation

This analysis thread starts with the level 1 event file. Before beginning, users may wish to reprocess the data with chandra_repro to create a new event file with the most recent calibration applied.

It is also suggested that users set the observation-specific bad pixel file, as described in the Setting the Observation-specific Bad Pixel Files thread.


Get Started

Download the sample data: 3 (HETG/ACIS-S, Trapezium Cluster)

unix% download_chandra_obsid 3 evt1,flt,asol
[NOTE]
Early dataset

The data used in this thread was taken very early in the Chandra mission. It was not included in the bulk reprocessing metioned in the Watchout page. The keywords required for analysis with CIAO need to be added by running chandra_repro or r4_header_update.

In this thread, we assume that all relevant files are in the same working directory.


Generate a New Level=1.5 Event File

1. Get position of zero-order images (tgdetect)

To find the zero-order locations, the tool tgdetect is run. The tgdetect2 tool identifies only the single brightest source and therefore is not useful for this particular thread. When processing multiple sources, the number of sources detected is determined by the tgdetect snr_thresh and snr_ratio_limit parameters. We also use a small fixedcell value to prevent multiple sources in close proximity from being grouped together.

unix% punlearn tgdetect
unix% pset tgdetect infile=acisf00003_000N004_evt1.fits
unix% pset tgdetect outfile=acis_3_src1a.fits
unix% pset tgdetect fixedcell=6
unix% pset tgdetect snr_thresh=20
unix% pset tgdetect snr_ratio_limit=0.25
unix% tgdetect
Input L1 event file (acisf00003_000N004_evt1.fits): 
Input source position(s) file from previous OBI or NONE (NONE): 
Output source position(s) file name (acis_3_src1a.fits):

The warning may be ignored; it is due to a minor bug in the Data Model and does not affect the output of tgdetect.

The contents of the parameter file may be checked using plist tgdetect.

Values for snr_thresh and snr_ratio_limit may be modified depending on how many sources you would like to detect. snr_thresh is the minimum signal to noise ratio that will be considered as a source. snr_ratio_limit is the ratio of the signal to noise ratio of the primary source to that of any other potential source that will be accepted as a source. If unsure of the proper values to use for these keywords it may be a good idea to run tgdetect first with excessively low values (snr_thresh=5, snr_ratio_limit=0.01). Inspect the SNR column of the output file and choose a snr_thresh just under the value for the faintest source you would like detected. Choose a sufficiently low snr_ratio_limit to include this source.

dmlist shows that there are seven sources in the file (one per row):

unix% dmlist acis_3_src1a.fits blocks

--------------------------------------------------------------------------------
Dataset: acis_3_src1a.fits
--------------------------------------------------------------------------------

     Block Name                          Type         Dimensions
--------------------------------------------------------------------------------
Block    1: PRIMARY                        Null
Block    2: SRCLIST                        Table        32 cols x 7        rows

The source list may be viewed over the event file using ds9:

unix% ds9 acisf00003_000N004_evt1.fits &

Overlay the source list: Region → Load Regions → acis_3_src1a.fits. Figure 1 shows the source list on the event file.


2. Get region mask (tg_create_mask)

The location of the HEG and MEG "arms" needs to be found next, via the tool tg_create_mask. This tool creates a region file that will be used later to mask the events:

unix% punlearn tg_create_mask
unix% pset tg_create_mask infile=acisf00003_000N004_evt1.fits
unix% pset tg_create_mask outfile=acis_3_evt1_L1a.fits
unix% pset tg_create_mask input_pos_tab=acis_3_src1a.fits
unix% tg_create_mask
Input event file or stack (acisf00003_000N004_evt1.fits): 
Output region file or stack (acis_3_evt1_L1a.fits): 
Input table with zero order positions or stack (acis_3_src1a.fits): 
Observed grating type (header_value|HETG|HEG|MEG|LETG) (HETG|HEG|MEG|LETG|header_value|HEADER_VALUE) (header_value): 

The contents of the parameter file may be checked using plist tg_create_mask.

The region file, acis_3_evt1_L1a.fits, will be used to mask the event file. The regions may be viewed over the event file using ds9:

unix% ds9 acisf00003_000N004_evt1.fits &

Overlay the region file: Region → Load Regions → acis_3_evt1_L1a.fits, as shown in Figure 2.

[Thumbnail image: The region mask outlines the photons from the source and the grating arms.]

[Version: full-size]

[Print media version: The region mask outlines the photons from the source and the grating arms.]

Figure 2: Event file with region file overlaid

The regions are loaded from the L1a.fits file, which was made by tg_create_mask.

dmlist shows that there are three rows for each detected source - a zero-order region and the two diffracted arms (HEG and MEG):

unix% dmlist acis_3_evt1_L1a.fits blocks

--------------------------------------------------------------------------------
Dataset: acis_3_evt1_L1a.fits
--------------------------------------------------------------------------------

     Block Name                          Type         Dimensions
--------------------------------------------------------------------------------
Block    1: PRIMARY                        Null
Block    2: REGION                         Table         8 cols x 21       rows

tg_create_mask will only create a mask for the first ten sources. If there are more than ten sources of interest, the tool must be run multiple times with a filter on the input_pos_tab filename:

unix% pset tg_create_mask input_pos_tab=acis_3_src1a.fits"[SRCLIST][tg_srcid=11:20]"

Alternatively, user source parameters may be explicitly set. This is somewhat tedious, but gives manual control over the resulting regions (see plist tg_create_mask for detailed comments and an example). radius_factor_zero is the size of the circle around the source and width_factor_hetg is the width of the grating arms in the mask created. If the default mask is too large with respect to nearby sources, then counts could be easily associated with the wrong source. The default values are for isolated sources and are wide enough to provide source and background regions later when binning with tgextract.


3. Run tg_resolve_events

The tool tg_resolve_events is now used to assign grating events to spectral orders, using the detector energy resolution for order separation:

unix% punlearn tg_resolve_events
unix% pset tg_resolve_events infile=acisf00003_000N004_evt1.fits
unix% pset tg_resolve_events outfile=acis_3_evt1a.fits
unix% pset tg_resolve_events regionfile=acis_3_evt1_L1a.fits
unix% pset tg_resolve_events acaofffile=@pcad_asol1.lis
unix% tg_resolve_events
Input event file or stack (acisf00003_000N004_evt1.fits):
Input region file or stack (acis_3_evt1_L1a.fits):
Output event file or stack (acis_3_evt1a.fits):
Input aspect offset file (@pcad_asol1.lis):

In many cases, there will be more than one aspect solution file (pcad_asol1.fits) for an observation. All the files must be input to the acaofffile parameter in chronological order (the time is in the filename, so "ls" lists them in order), either as a comma-separated list or as a stack. Here we use:

unix% cat pcad_asol1.lis 
pcadf057736899N004_asol1.fits
pcadf057763996N004_asol1.fits

The contents of the parameter file may be checked using plist tg_resolve_events. The event file columns relevant to multiple sources are TG_SRCID and TG_SMAP. Where orders cross spatially, events may still be resolved via the PHA information (see the Chandra Grating Analysis Page).


Generate a New Level=2 Event File

1. Apply grade/status filters (dmcopy)

Filter for bad grades and for a "clean" status column (i.e. all bits set to 0):

unix% punlearn dmcopy
unix% dmcopy "acis_3_evt1a.fits[EVENTS][grade=0,2,3,4,6,status=0]" \
      acis_3_flt1_evt1a.fits opt=all

2. Apply GTI filters (dmcopy)

The Good Time Intervals (GTIs) supplied by the pipeline now need to be applied. We simultaneously eliminate an unnecessary column from the output:

unix% punlearn dmcopy
unix% dmcopy \
      "acis_3_flt1_evt1a.fits[EVENTS][@acisf00003_000N004_flt1.fits][cols -phas]" \
      acis_3_evt2.fits opt="" 

unix% dmappend \
      "acis_3_flt1_evt1a.fits[region][subspace -time]" \
      acis_3_evt2.fits

Be sure to include the @ symbol in the filter expression; the command will not be executed properly if it is omitted.

The opt="" parameter in dmcopy and the dmappend command are a workaround for the bug in time-filtering grating data.


Extract Grating Spectra (tgextract)

The CIAO tool tgextract produces a spectrum file from the level=2 event file:

unix% punlearn tgextract
unix% pset tgextract infile=acis_3_evt2.fits
unix% pset tgextract outfile=acis_3_pha2.fits
unix% tgextract
Input event file (output event file from L1.5 processing) (acis_3_dstrk_evt2.fits): 
If typeII, enter full output file name or '.'; if typeI, enter output rootname (acis_3_pha2.fits):
Input ancillary response file name (none): 
Input redistribution file name (none): 
Source ID's to process: 'all', comma list, @file (all): 
Grating parts to process: HETG, HEG, MEG, LETG, header_value (HETG|HEG|MEG|LETG|header_value) (header_value): 
Grating diffraction orders to process: 'default', comma list, range list, @file (default): 
Ouput file type: typeI (single spectrum) or typeII (multiple spectra) (pha_typeI|pha_typeII) (pha_typeII): 

To extract spectra for specific sources from the event file, use the tg_srcid_list parameter (see ahelp tgextract for more information).

The contents of the parameter file may be checked using plist tgextract.

Using dmlist, we can examine the output file:

unix% dmlist acis_3_pha2.fits blocks                                                                        
--------------------------------------------------------------------------------
Dataset: acis_3_pha2.fits
--------------------------------------------------------------------------------
 
     Block Name                          Type         Dimensions
--------------------------------------------------------------------------------
Block    1: PRIMARY                        Null        
Block    2: SPECTRUM                       Table        13 cols x 84       rows
Block    3: REGION                         Table        10 cols x 252      rows

There are 12 rows for each of the 7 identified sources, making a total of 84 rows in the file. Since there are three regions associated with each order (source, upper background, and lower background), the REGION block contains 252 rows. For more examples of viewing PHA2 files, see the Examining Grating Spectra thread.


Grouping the Spectra

In order to use Gaussian statistics to fit a model to a dataset, it is often necessary to "group" the data - i.e. combine channels until you have enough counts. Before fitting the data in Sherpa, read the Grouping a Grating Spectrum thread for more information.


Summary

This thread is complete; the grating spectrum file is named acis_3_pha2.fits. You should now proceed to the ACIS-S Grating RMFs thread.

In order to use Gaussian statistics to fit a model to a dataset, it is often necessary to "group" the data - i.e. combine channels until you have enough counts. Before fitting the data in Sherpa, read the Grouping a Grating Spectrum thread for more information.



Parameters for /home/username/cxcds_param/tgdetect.par


##
## TGDETECT -- Create filter; run celldetect; narrow down detected
##             'zero order' source list; set source id's; match 
##             sources to previous OBI source list.
##
## Note: if either "infile" or "OBI_srclist_file" are @lists, only
## the first item on the list is read in;  this tool only works on
## one set of input files;  if more than one file is listed, 
## everything but the first are ignored.
##
        infile = acisf00003_000N004_evt1.fits   Input L1 event file
OBI_srclist_file = NONE             Input source position(s) file from previous OBI or NONE
       outfile = acis_3_src1a.fits  Output source position(s) file name
#
#   output file naming
#
     (temproot = )                Path and root file name to be given to temporary files
     (keeptemp = no)              Keep temporary files?
     (keepexit = no)              Keep exit status file?
#
#
#
     (zo_pos_x = default)         Center GZO filter sky X position (default=pixel(ra_nom))
     (zo_pos_y = default)         Center GZO filter sky Y position (default=pixel(dec_nom))
 (zo_sz_filt_x = default)         Size of GZO filter in X pixels (ACIS=400; HRC=1800)
 (zo_sz_filt_y = default)         Size of GZO filter in Y pixels (ACIS=400; HRC=1800)
   (snr_thresh = 20)              SNR threshold to select the detected sources
# 
#   celldetect parameters
#
       (expstk = none)            list of exposure map files
       (thresh = )celldetect.thresh -> 3) celldetect source threshold
     (ellsigma = 3.0)             Size of output source ellipses (in sigmas)
     (expratio = 0)               cutoff ratio for source cell exposure variation
    (findpeaks = yes)             find local peaks for celldetect
(celldetect_log = )celldetect.log -> no) make a celldetect log file?
     (psftable = )celldetect.psftable -> /soft/ciao/data/psfsize20010416.fits) table of PSF size data, for celldetect
    (fixedcell = 6)               celldetect fixed cell size to use
(fixedcell_cc_mode = 15)              celldetect fixed cell size to use for CC mode ACIS data
      (bkgfile = none)            background file, for celldetect
     (bkgvalue = )celldetect.bkgvalue -> 0) background count/pixel, for celldetect
  (bkgerrvalue = )celldetect.bkgerrvalue -> 0) background error, for celldetect
        (eband = )celldetect.eband -> 1.4967) energy band, for celldetect
      (eenergy = )celldetect.eenergy -> 0.8) encircled energy of PSF, for celldetect
      (snrfile = none)            celldetect snr output file (for convolution only)
     (convolve = )celldetect.convolve -> no) use convolutions for celldetect
      (xoffset = INDEF)           celldetect offset of x axis from optical axis
      (yoffset = INDEF)           celldetect offset of y axis from optical axis
     (cellfile = none)            output cell size image file
     (centroid = yes)             compute source centroids in celldetection?
#
#   tgidselectsrc parameters
#
(snr_ratio_limit = 0.25)            Value of SNR ratio to use as lower limit
     (setsrcid = )tgidselectsrc.setsrcid -> yes) Set src ids in output file?
#
#   tgmatchsrc parameters
#
(max_separation = )tgmatchsrc.max_separation -> 3) Maximum allowed separation (arcsec) for sources to match
#
#
      (clobber = no)              OK to overwrite existing output file(s)?
      (verbose = 0)               Verbosity level (0 = no display)
         (mode = ql)              




Parameters for /home/username/cxcds_param/tg_create_mask.par


##
## TG_CREATE_MASK -- Calculates the mask regions of the grating arms
##    for AXAF flight L1 grating data files.  The output is a region
##    file(s) in sky coordinates.
##
        infile = acisf00003_000N004_evt1.fits   Input event file or stack
       outfile = acis_3_evt1_L1a.fits Output region file or stack
 input_pos_tab = acis_3_src1a.fits  Input table with zero order positions or stack
   grating_obs = header_value     Observed grating type (header_value|HETG|HEG|MEG|LETG)
     sA_zero_x = 1                Source A - x position of zero order
     sA_zero_y = 1                Source A - y position of zero order
     sB_zero_x = 1                Source B - x position of zero order
     sB_zero_y = 1                Source B - y position of zero order
     sC_zero_x = 1                Source C - x position of zero order
     sC_zero_y = 1                Source C - y position of zero order
     sD_zero_x = 1                Source D - x position of zero order
     sD_zero_y = 1                Source D - y position of zero order
     sE_zero_x = 1                Source E - x position of zero order
     sE_zero_y = 1                Source E - y position of zero order
     sF_zero_x = 1                Source F - x position of zero order
     sF_zero_y = 1                Source F - y position of zero order
     sG_zero_x = 1                Source G - x position of zero order
     sG_zero_y = 1                Source G - y position of zero order
     sH_zero_x = 1                Source H - x position of zero order
     sH_zero_y = 1                Source H - y position of zero order
     sI_zero_x = 1                Source I - x position of zero order
     sI_zero_y = 1                Source I - y position of zero order
     sJ_zero_x = 1                Source J - x position of zero order
     sJ_zero_y = 1                Source J - y position of zero order
(input_psf_tab = CALDB)           Calibration file with mirror psf vs off-axis angle
     (detector = header_value)    Detector type: ACIS | HRC-I | HRC-S | header_value
(radius_factor_zero = 50)              A scale factor which multiplies the app. calculation of the one-sigma
(width_factor_hetg = 35)              A scale factor which multiplies the one-sigma width of the heg/meg mask
(width_factor_letg = 40)              A scale factor which multiplies the one-sigma width of the letg mask in
(r_astig_max_hetg = 0.5600000000000001) Max grating r coord (deg, along the dispersion) for HETG astigmatism
(r_astig_max_letg = 1.1)             Max grating r coord (deg, along the dispersion) for LETG astigmatism calc
(r_mask_max_hetg = 0.992)           Max grating r coord (deg) for HETG mask (to support offset pointing)
(r_mask_max_letg = 2.1)             Max grating r coordinate (deg) for LETG mask (to support offset pointing)
# --------------------------------------------------------------------------
# The parameters below are to be set ONLY if the user wants to use their
# own grating mask sizes instead of having the masks automatically generated.
# Only ONE input file, with up to 10 soures, can be processed using the user 
# params.  @ lists of multiple files can only be done with automated mask
# processing, or by running each file individually with hand set mask sizes.
# To start, you MUST set the following parameters:
#
# > pset tg_create_mask use_user_pars=yes last_source_toread=[letter A -> J]
#
# The parameter last_source_toread should be set to the last source letter
# for which you will enter parameters.  If you want to input 2 sources 
# (regardless of their source id's), the last_source_toread=B. Sections
# A -> J are for (upto) 10 user specified sources.  In each sections, 
# each source must have an ID, a zero order center position specified, 
# as well as the grating mask width(s).  An example with 2 HETG sources, 
# with src_id's 6 and 3:
#
# > pset tg_create_mask use_user_pars=yes last_source_toread=B
# > pset tg_create_mask sA_id=6 sA_zero_x=4762.34 sA_zero_y=2344.29 
# > pset tg_create_mask sA_zero_rad=35 sA_width_heg=25 sA_width_meg=28
# > pset tg_create_mask sB_id=3 sB_zero_x=4063.54 sB_zero_y=6346.62 
# > pset tg_create_mask sB_zero_rad=45 sB_width_heg=50 sB_width_meg=75
#              (units are all in sky pixels)
#
# NOTE: for Continuous Clocking data (CC mode), the HETG mask does not
# require the s#_width_heg, since the meg mask will encompase the entire
# data set.  HEG event processing in CC mode is done using the next 
# tool tg_resolve_events.
# --------------------------------------------------------------------------
(use_user_pars = no)              Use the user defined mask parameters below: yes or no?
(last_source_toread = A)               Last source name to be read; character A->J.
# --------------------------------------------------------------------------
# 			Source A parameters
# --------------------------------------------------------------------------
        (sA_id = 1)               Source A - source id number
  (sA_zero_rad = )                Source A - radius of zero order mask
 (sA_width_heg = )                Source A - width of heg mask in sky pixels
 (sA_width_meg = )                Source A - width of meg mask in sky pixels
 (sA_width_leg = )                Source A - width of leg mask in sky pixels
..(through Source J)..
      (geompar = geom)            Parameter file for Pixlib Geometry files
      (verbose = 0)               Verbose level: 0 - no output, 5 - max verbosity
      (clobber = no)              Clobber existing outfile?
         (mode = ql)              




Parameters for /home/username/cxcds_param/tg_resolve_events.par


#--------------------------------------------------------------------------
#
#   tg_resolve_events.par: Parameter file for the tg_resolve_events program
#
#--------------------------------------------------------------------------
        infile = acisf00003_000N004_evt1.fits   Input event file or stack
       outfile = acis_3_evt1a.fits  Output event file or stack
    regionfile = acis_3_evt1_L1a.fits Input region file or stack
    acaofffile = @pcad_asol1.lis  Input aspect offset file
(alignmentfile = )acaofffile -> @pcad_asol1.lis) Input sim offset file
      (logfile = stdout)          Output log (NONE|<filename>|stdout)
# The osipfile contains position dependent energy limits based on
# the CCD resolution, used for order-sorting.
# A value of "NONE" means that the file will not be used, and
# that the parameters, osort_hi and osort_lo will be used.
     (osipfile = CALDB)           Lookup table for order resolving (for acis data only)
#sort_hi, osort_lo specify fractional deviations from the integer
#order which will be included in order-sorting via CCD ENERGY values (PHA).
#eg. osort_lo-0.3, osort_hi=0.2 means that photons with real-valued
#orders between 0.7 < order <= 1.2 will be included in first order,
#1.7 < order <= 2.2 will be second order, etc.
     (osort_lo = 0.3)             Order-sorting lower bound fraction; order > m - osort_lo
     (osort_hi = 0.3)             Order-sorting high bound fraction; order <= m + osort_hi
  (grating_obs = header_value)    Observed grating type (header_value|HETG|HEG|MEG|LETG)
     (detector = header_value)    Detector type: ACIS | HRC-I | HRC-S | header_value
(energy_lo_adj = 1.0)             Lower Energy limit factor
(energy_hi_adj = 1.0)             Upper Energy limit factor
  (time_offset = 0)               Offset to add to event time to synch w/ alignment data
    (rand_seed = 1)               Random seed (for pixlib), 0 = use time dependent seed
(rand_pix_size = 0.0)             pixel randomization width (-size..+size), 0.0 = no randomization
     (eventdef = )stdlev1_ACIS -> {d:time,i:expno,f:rd,s:chip,s:tdet,f:det,f:sky,s:ccd_id,l:pha,s:pi,
f:energy,s:grade,s:fltgrade,s:node_id,s:tg_m,f:tg_lam,f:tg_mlam,s:tg_srcid,s:tg_part,s:tg_smap,x:status})
Output format definition
      (stdlev1 = )eventdef -> {d:time,i:expno,f:rd,s:chip,s:tdet,f:det,f:sky,s:ccd_id,l:pha,s:pi,f:energy,
s:grade,s:fltgrade,s:node_id,s:tg_m,f:tg_lam,f:tg_mlam,s:tg_srcid,s:tg_part,s:tg_smap,x:status}) 
 (stdlev1_ACIS = {d:time,i:expno,f:rd,s:chip,s:tdet,f:det,f:sky,s:ccd_id,l:pha,s:pi,f:energy,s:grade,
s:fltgrade,s:node_id,s:tg_m,f:tg_lam,f:tg_mlam,s:tg_srcid,s:tg_part,s:tg_smap,x:status})
ACIS event format definition string
  (stdlev1_HRC = {d:time,f:rd,s:chip,l:tdet,f:det,f:sky,s:chip_id,s:pha,s:pi,s:tg_m,f:tg_lam,f:tg_mlam,
s:tg_srcid,s:tg_part,s:tg_smap,x:status}) HRC event format definition string
# --------------------------------------------------------------------------
      (geompar = geom)            Parameter file for Pixlib Geometry files
      (verbose = 0)               Verbosity level of detail (0=none, 5=most)
      (clobber = no)              Clobber outfile if it already exists?
         (mode = ql)              




Parameters for /home/username/cxcds_param/tgextract.par


##
## TGEXTRACT -- create 1D spectrum(a) table file(s) from the
##              L1.5 output event list
##
        infile = acis_3_evt2.fits Input event file (output event file from L1.5 processing)
       outfile = acis_3_pha2.fits   If typeII, enter full output file name or '.'; if typeI, enter output rootname
#
# tg_srcid_list parameter explanation...
#  - "all" will process all the sources id's found in the event list
#  - a comma list is a comma separated string list of all the 
#    sources to process, ie:
#       "1,2,5,7"
#  - @file is a pointer to an ascii file which contains a comma
#    separated list of the id's to process
#
 tg_srcid_list = all              Source ID's to process: 'all', comma list, @file
  tg_part_list = header_value     Grating parts to process: HETG, HEG, MEG, LETG, header_value
#
# tg_order_list parameter explanation...
#  - "default" is set to process the following:
#       if ACIS:  1, 2, 3, -1, -2, -3
#       if HRC:   -1, 1
#  - a comma list is a comma separated string list of the orders
#    the user wants to process, ie:
#       "-5, -1, 1, 3"
#  - a range list sets the min and max of the orders to process;
#    all the orders in between, will be processed, ie:
#       "-1..5"  will do orders from -1 to +5th order
#    a range list can be mixed with comma separated list
#  - @file is a pointer to an ascii file which contains a comma
#    separated list and/or range list of the orders to process
#
 tg_order_list = default          Grating diffraction orders to process: 'default', comma list, range list, @file
      ancrfile = none             Input ancillary response file name
      respfile = none             Input redistribution file name
  outfile_type = pha_typeII       Ouput file type: typeI (single spectrum) or typeII (multiple spectra)
(inregion_file = none)            Input region file.
     (backfile = none)            Input background file name
        (rowid = )                If rowid column is to be filled in, enter name here
    (bin_units = angstrom)        Bin units (for bin parameters below): angstrom, eV, keV
  (min_bin_leg = compute)         Minimum dispersion coordinate for LEG, or 'compute'
  (max_bin_leg = compute)         Maximum dispersion coordinate for LEG, or 'compute' 
 (bin_size_leg = compute)         Bin size for binning LEG spectra, or 'compute'
 (num_bins_leg = compute)         Number of bins for the output LEG spectra, 'compute'
  (min_bin_meg = compute)         Minimum dispersion coordinate for MEG, or 'compute'
  (max_bin_meg = compute)         Maximum dispersion coordinate for MEG, or 'compute'
 (bin_size_meg = compute)         Bin size for binning MEG spectra, or 'compute'
 (num_bins_meg = compute)         Number of bins for the output MEG spectra, or 'compute'
  (min_bin_heg = compute)         Minimum dispersion coordinate for HEG, or 'compute'
  (max_bin_heg = compute)         Maximum dispersion coordinate for HEG, or 'compute'
 (bin_size_heg = compute)         Bin size for binning HEG spectra, or 'compute'
 (num_bins_heg = compute)         Number of bins for the output HEG spectra, 'compute'
     (min_tg_d = default)         Minimum tg_d range to include in histogram, or use 'default'
     (max_tg_d = default)         Maximum tg_d range to include in histogram, or use 'default'
(extract_background = yes)             Extract the local background spectrum?
(min_upbkg_tg_d = default)         Minimum value of tg_d for the background up spectrum.
(max_upbkg_tg_d = default)         Maximum value of tg_d for the background up spectrum.
(min_downbkg_tg_d = default)         Minimum value of tg_d for the background down spectrum.
(max_downbkg_tg_d = default)         Maximum value of tg_d for the background down spectrum.
      (geompar = geom)            Parameter file for Pixlib Geometry files
      (clobber = no)              OK to overwrite existing output file(s)?
      (verbose = 0)               Verbosity level (0 = no display)
         (mode = ql)              



History

16 Dec 2004 updated for CIAO 3.2: minor changes to parameter files; default extraction width in tgextract has been widened to 0.002 degrees (removed manual setting of parameters in the Extract Grating Spectra section)
12 Jan 2005 remove incorrect statement about destreaking pipeline file from Overview
14 Jan 2005 created the Data Preparation section
05 Dec 2005 updated for CIAO 3.3: output filenames include ObsID; parameter file changes (kernel parameter removed from all "tg" tools; several changes to the destreak parameter file, including a new default value for the mask parameter)
05 Jan 2006 information on reprocessing included in Data Preparation section
04 Apr 2006 expanded information on special cases in the Get position of zero-order image (tgdetect) section
01 Dec 2006 updated for CIAO 3.4: change to wording of tgdetect/dmcopy warning
11 Jan 2008 updated for CIAO 4.0: ds9 now automatically looks for the "[REGION]" or "[SRCLIST]" extension in the region file, so it doesn't have to be specified; removed outdated calibration updates; filenames updated for reprocessed data (version N003 files)
12 Feb 2009 updated for CIAO 4.1: images converted to inline; tg_resolve_events no longer prints the "dsTREUNKNOWNINCOLERR -- WARNING: Not loading data from unrecognized level 1.5 input column." message, as it does not affect data analysis; input data must have a CTI_APP keyword
19 Feb 2009 added grouping information to the Summary
14 Jan 2009 updated for CIAO 4.2: ObsID 3 file versions and corresponding minor screen changes
12 Jan 2011 reviewed for CIAO 4.3: no changes
25 Mar 2011 added workaround for GTI filtering bug to the Apply GTI filter section
06 Jan 2012 reviewed for CIAO 4.4: the destreak tool is now run in the reprocessing thread
03 Dec 2012 Review for CIAO 4.5; minor edits
11 Dec 2013 Review for CIAO 4.6. Added note about why not to use tgdetect2
22 Dec 2014 Reviewed fro CIAO 4.7; minor edits only.


Last modified: 22 Dec 2014
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