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FTOOLS v3.5 released
Version 3.5 of FTOOLS (including XSELECT) is now available on
legacy.gsfc.nasa.gov anonymous ftp account in directory
software/ftools/release --- please check the files README and
Release_notes_3.5 for such details as a list of supported platforms;
installation instructions; and a list of new and updated ftools
that are not ASCA-specific. The rest of this message contains details
of ASCA-specific changes.
Highlights: (1) New access method for calibration files have
been incorporated into several ASCA FTOOLS; (2) Substantial
changes have been made to FAST mode related ftools, but sisrmg
does not work properly for fast mode pha files yet; (3) Sisrmg
now generates time-dependent response matrices, including the
effects of non-uniform CTI; (4) A completely re-written version
of faintdfe reduces the ill effects of RDD.
I. REFDATA vs CALDB
We are planning to phase out refdata area and migrate to the calibration
database (caldb) structure. The indexing system in caldb will enable
users to automatically pick up the latest calibration file that is applicable
to the data file in question. Large X-ray astronomy groups, which support
many users who analyze multiple datasets on a regular bases, are encouraged
to install caldb now. Many ASCA Ftools will accept "CALDB" in
lieu of the full pathname of the calibration file they require; however,
this requires the user's site to have installed caldb and the user to have
initialized caldb (see caldb/docs/manuals/user/users_guide.tex in
legacy.gsfc.nasa.gov anonymous ftp account).
We recognize that a transition period is required during which only some
of the users can take advantage of the caldb. This is a special concern
for use of these ftools within XSELECT or in distributed script. See the
note on sispi below for an example of how we have provided for this transition
New calibration files: most noteworty is sisph2pi_290296.fits,
which is (more or less) simultaneously released in the refdata area
and in CALDB. This extends the SIS gain history calibration, and
also incorporates the updated calibration of relative gain of 8 CCD
chips on the SIS instruments.
II. FAST MODE DATA ANALYSIS
As of this writing, sisrmg does not work correctly for fast mode spectral
files. A patch will be announced as soon as the bug is fixed.
We have made a substantial revisions in the FTOOLS/XSELECT for fast mode
data. With this new version, all essential information will be passed
from raw science fits files to the extracted spectra, to be read by
sisrmg and ascaarf to generate the appropriate response. (Previously,
generating the correct arf involved the use of a dummy spectral file
in bright mode.)
Please note that it is best to start from the raw science files if
you wish to use the new sisrmg/ascaarf on fast mode data, using ascascreen.
In particular, fast mode event files that were created & saved after a
"select fast" command in XSELECT will not have correct header keywords
for this to work. Also the WMAP image as well as header keywords in
any old fast mode spectral files are defficient.
III. UPDATED OR NEW FTOOLS:
This version, v1.0, includes two major changes:
* A completely new interface, which relies heavily on information in the
spectral (*.pha) file itself. When the raw science files are combined
using the latest version of FTOOLS to (eventually) produce the SIS spectral
file, all necessary keywords except one can be found in the FITS header
of the pha file. The exception is the history of grade selection --- although
the selection is written into a human-readable history keyword, we do not
have the capability yet to produce a machine-friendly version. Thus sisrmg
will assume the standard grade selection (grades 0, 2, 3 and 4 for imaging
modes; fast mode grade 0), which the user can override using a hidden
For older pha files, or new pha files produced from older event files,
sisrmg will use a set of defaults for some missing keywords. Roughly
speaking, this is equivalent to using the 'standard' matrices copied
from the legacy anonymous ftp area, and will work fine for the vast
majority of data. However, if a non-standard setting has been used,
users can either use hidden parameters or re-extract the spectrum from
For this version of sisrmg, as well as all versions of ascaarf, to work
correctly, it is essential that a region file be applied in xselect
before the spectrum is extracted. If you do not apply any region file
(e.g., to extract the spectrum from the entire chip in an 1-CCD mode
observation), or if event file for a specific region is extracted,
saved then read into a new Xselect session, the pha files produced
will not contain a correct WMAP, a low resolution detector map of where
the extracted counts were from, and sisrmg and ascaarf will therefore
not work correctly.
* Inclusion of energy resolution degradation due to non-uniform CTI:
The broadening of response features with time has been characterized
and included in sisrmg v1.0.
As mentioned above, the current release does not work for fast mode data.
This is a completely new version, from the orignial developed by Dr. Otani
at Riken. This was necessary to handle the skewed distribution of zero
levels that resulted from RDD. A new calibration file, faintdfe.tbl,
that characterizes the skewed distribution as a function of CCD clocking
mode and time of observation, is inculded in the refdata area. Moreover,
due to the skewness of the distribution, the very definition of the zero
level has become ambiguous. We now have introduced 3 definitions:
zerodef=0: the old definition, this accentuates the loss of
efficiency and apparent energy shift due to RDD.
zerodef=1: the new definition, the RDD effects are minimized.
zerodef=2: mimics the on-board processing for bright mode,
but taking out the orbital day/night difference.
The output DFE files from the new faintdfe will have a line preceded by '!'
denoting the zero level definition used. We recommend zerodef=1 for
Bright2 mode, and zerodef=2 for Bright mode.
This program takes an ASCII output file from faintdfe and inserts the values
in the appropriate columns of the mkf file. This has been updated to be
able to handle the '!' line from new faintdfe.
This version of faint includes time-dependent echo correction, and is
capable of handling the DFE file produced by the new faintdfe.
Now incorporates CALDB access; for use within Xselect, the SIS Gain History
file can be specified as 'AUTO' --- sispi will first try CALDB, and if it
fails, it will look for sisdata/sisph2pi_290296.fits under the FTOOLS refdata
area. This version of sispi also incorporates a reorganized set of subroutines
which are now shared between sispi and ascalin.
XSELECT may call faintdfe, faint, sispi and fastwmap; all these ftools have
changed, and these have to be matched by changes in XSELECT. Some
incompatibility problems experienced in FTOOLS v3.4 versions are believed
to have been solved. The new version of fastwmap is believed to create
the WMAP correctly for all fast mode data.
Substantial modifications have been made to FASTWMAP and it is now
believed to be correct and much easier to use. The only parameters
now required are the input filename, the output filename, and the
WMAP bin size. All other information is read from the input file.
CALDB access is incorporated for the calfile parameter - if this
is set to 'AUTO' then the calibration database is used and if that
is not available the FTOOLS refdata area.
(8) ASCAARF and ASCAEFFMAP:
These have both been updated to use the latest releases of the
XRT software (XRT_RSP_v1.4d) and GIS efficiency (v4.0). CALDB
access is incorporated in both FTOOLS.
There are GIS monitor counts called G2_L1 and G3_L1 in the GIS house-keeping
files. These monitor counts have a time resolution of 0.125 sec (for high
bit rate) or 1.0 sec (for medium bitrate), and do not have energy nor spatial
resolutions. The maximum counting rate is 2048 cts/s/GIS (for high bitrate),
much larger than that of the GIS PH mode data (128 cts/s/GIS). Hence these
monitor counts are useful to study time variations of bright sources.
Ghkcurve produces a FITS format light curve file using G2_L1 or G3_L1 value in
the input GIS house keeping file. Users are requested to specify the good
time interval (in the FITS file), as well as the time resolution (0.125 sec
or 1.0 sec according to the bitrate).
- Koji Mukai for the ASCA GOF