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FTOOLS v4.0 released



FTOOLS V4.0 RELEASED

We are pleased to announce the release of FTOOLS v4.0.  In this message,
we summarize:

	1. How to obtain FTOOLS v4.0
	2. Impact on ASCA users
		2a. New/updated tasks in v4.0
		2b. A note for users of XTE update v3.6.1
	3. Known bugs/deficiencies of FTOOLS v4.0

---------------------------------------------------------------
1. How to obtain FTOOLS v4.0
---------------------------------------------------------------
   FTOOLS v4.0 has been released, and can be obtained from the
FTOOLS web-page at:

   http://heasarc.gsfc.nasa.gov/docs/software/ftools/ftools_menu.html

This is where the most up to date FTOOLS information is available,
including notices of the FTOOLS Releases, online HTML versions of FTOOLS
documentation, and the continually updated FAQ.  Users should always check
here first for answers to questions.

Any problems installing FTOOLS should be reported to:

                ftoolshelp@athena.gsfc.nasa.gov

Any problems using FTOOLS for ASCA data analysis should be reported
to the ftoolsheelp address above or to:

		ascahelp@athena.gsfc.nasa.gov

If the problem relates to the scientific contents of the FTOOLS,
the latter address is more appropriate.
---------------------------------------------------------------

---------------------------------------------------------------
2. Impact on ASCA users
---------------------------------------------------------------

                -----------------------------
                2a. New/updated tasks in v4.0
                -----------------------------

* Rbnpha

This tool now follows the channel numbering convention of the input file.

Both SIS and GIS event files are numbered from channel 0, and therefore
the extactor originally creates the spectral files that also start with
channel 0.  However, old versions of rbnpha (which is run by default when
extracting SIS spectra in xselect) used numbers starting with channel 1
in the output files.  With this new version, rbnpha will respect the channel
numbering convention of the input file, which solves several problems such
as encountered in adding GIS-2 and GIS-3 spectra taken while GIS-3 was
suffering the bit problem.

IMPORTANT: You need xspec 9.02 or later, or else there will be a suprious
1-channel shift in the SIS spectral analysis.  If you use your own spectral
analysis package, please contact ascahelp to make sure your software interprets
the latest SIS response matrices correctly.

* Ascascreen

Ascascreen now uses *.unf files as default input; to use raw *.fits files,
specify 'ascascreen -e fits'.  Ascascreen now uses a more sensible threshold
(4 times readout cycle) for SIS t_dy_nt and t_saa screening (time after
day/night transitions and time after SAA passages), and new region files to
remove the outer ring and the calibration source for the GIS.  It also has
a more advanced GIS screening criteria for background removal (rather than
the current scheme of relying heavily on COR); it will also have different
region files for removing the background ring for spread discriminator off
data.

The problem in previous versions, where the standard region selection
for GIS 64x64 spatial resolution mode failed, has been fixed.

* Xselect / extractor

The program that is run by the xselect "extract" or "bin" command
has been extensively overhauled and is available as an ftool called
extractor. See "fhelp extractor" for details. A number of bugs have
been fixed in the region filtering. All regions with the exception
of circles were one pixel off in both dimensions. In addition, the
circle region did not always work correctly. Region filtering should
now work for all sizes of regions. Note that a good way to check
that the region filtering is correct is to extract a filtered image,
read it and the region file into SAOimage or SAOtng, and check that
all pixels with any part in the region were selected. Extractor now
uses dynamic memory so there is no (theoretical) limit to the size
of images that can be extracted. In particular, the problems extracting
ROSAT images at binning factors less than 15 have been fixed.

Xselect now supports SAX LECS and MECS.

* Sisrmg

The new version contains:
    + New FITS keywords that allow xspec to handle matrices that begin
	with channel 0
    + Correct treatment of the event threshold for PI spectra.
	*** IMPORTANT NOTE *** If you previously fudged FITS keywords of
	your spectral file(s) to 'fool' sisrmg into creating the correct
	response files, you should delete these spectral files.  The new
	version will only work correctly with unfudged spectra.
    + Gains=0 is now the default (previously -1) for constructing the
	energy-channel mapping; this will result in slight shifts for
	various spectral features (some better, some worse).  However,
	fitting results are independent of the gains parameter.
    + A primitive support for data processed with 'correctrdd' (see below).
	
* Addascaspec

This script combines the source and the background spectra and the
response files from different instruments or observations, and
takes care of the complex background normalization automatically.

* Ghkcurve

Ghkcurve now intersects the user's input Good Time Interval list with
the input housekeeping file's ALLGTI extension, if there is one.  The
merged GTI list is written in the output file, instead of just copying
the gtifile one.  The user can now specify which monitor count to read
with the new `monitor' parameter, and can say to not use an input GTI
with `gtifile=none' (the ALLGTI is still applied).  Ghkcurve now
writes checksum keywords, applies TIMEZERO keywords, uses the actual
first and last times for TSTART and TSTOP, can handle larger GTI
arrays, and resets the integration when an SF_LOST HK entry is
encountered.

* Ascaarf

Arf calculation for the GIS has been sped up by using an FFT to convolve
the telescope and detector point response functions. A new parameter
bkgfile can be used to specify an image to be subtracted from the WMAP
before calculating the arf.

* Ascaeffmap

Now uses an FFT to convolve the telescope and detector point response functions.

* Mekal and Raysmith

These are new ftools that can be used to run the Mewe-Kaastra-Liedahl
and Raymond-Smith equilibrium collisional plasma models and build an 
XSPEC table file. This file can be used to replace the one used by 
default in XSPEC if a different parameter or energy gridding is required.

* Genrsp

This ftool can be used to build test instrument response matrices. The
response is assumed to be gaussian with no escape features. A variety
of different dependences of resolution with energy or wavelength are
available.

* Fregcon

This ftool now works.

* Ffilecat

No longer requires filenames to be < 100 characters.

* Correctrdd

This new program allows Faint mode data to be corrected for the RDD
(residual dark distribution) effects.   Please regard this as a beta-test
version, in that the calibration of spectral response for RDD-corrected
data is still in an early stage.  Correctrdd should be run on Faint mode
files; although it can also be run on Bright mode files, the effects of
doing so are poorly understood; it is expected to be much less effective
than running it on Faint mode files.  Correctrdd requires RDD map files ---
these will be generated on request by the SIS team, although in future we
may be able to provide them in CALDB, for example.

* Ascaray

This is a beta-test FTOOLS version of the Nagoya University code
(ray2areav6_0cal) to ray trace the ASCA mirrors, with enhancements to the gold
atomic constants as implemented by GSFC's Keith Gendreau.  Since this is
the first release, users interested in using this code should make sure that
they contact both the ASCA GOF and the ray trace experts of Nagoya University
for information on valid parameter values for use with the code and
limitations on its use. Users should restrain their enthusiasm to use the
code to create non-standard calibrations that slighty improve spectral fits
until they have familiarized themselves with the large body of work already
performed by Nagoya and the GSFC staff.

                ----------------------------------------
                2b. Notes for users of XTE update v3.6.1
                ----------------------------------------

As noted earlier, the new version of rbnpha was included in v3.6.1, however
the corresponding update to sisrmg was incomplete, causing a spurious 1 channel
shift when analyzed using xspec.  If you have gotten around this problem by
inserting the 'TLMIN4' keyword in the response matrix, you need not take any
further action.

----------------------------------------------
3. Known bugs and defficiencies of FTOOLS v4.0
----------------------------------------------

* The current scheme used for spectral extractions in sky coordinates have
  limitations.  See
	http://heasarc.gsfc.nasa.gov/docs/asca/soft_skycoord.html
  for details.
* Note also that you need to specify a region file when extracting spectra,
  for sisrmg and ascaarf to generate correct responses.  If you extract
  an event file around the source first, then extract a spectrum from it
  without reapplying the region file, sisrmg and ascaarf will not work
  correctly.  Similarly, it will cause problems if you use a region file
  that extends beyond where the events are.