ROSAT Status Report #118:

Feb 27, 1995

Contents

• WFC 2RE Catalogue of EUV sources
• Reminder of a problem with coordinate determination using IRAF
• New ROSAT FTOOLS released

ROSAT Wide Field Camera 2RE Catalogue of EUV sources

Reprocessing of the ROSAT Wide Field Camera (WFC) all-sky survey database has resulted in a new catalogue, designated `2RE', containing 479 sources (Pye et al. 1995, MNRAS, in press). 120 of them were not reported in the previous, first WFC Bright Source Catalogue (BSC, Pounds et al. 1993, MNRAS, 260, 77); of these, 97 also do not appear in the first EUVE Catalogue (Bowyer et al. 1994, ApJS, 93, 569) and hence have not previously been reported at EUV wavelengths. 387 sources are now detected in both WFC survey wavebands. 444 sources have proposed identifications; these include 75 with late-type stars and 6 with hot white-dwarf stars, amongst the 120 new, `post-BSC' sources. 31 sources are found to be variable; all are identified, most with cataclysmic-variable stars or late-type stars (McGale et al. 1995, MNRAS, submitted).

The 2RE Catalogue and a preprint version of the MNRAS paper are available on-line via ftp, WWW and the LEDAS database node. A summary of the various access methods is given below.

     Via ftp

        ftp ledas-ftp.star.le.ac.uk
        Name: anonymous
        Password: username@site
        cd rosat/2re
        mget *                  (to copy all the files)
        ...
        bye

The file README contains a brief description of each file in the directory. These include: postscript (.ps) files of the text, main catalogue table and figures, and a plain ASCII text (.txt) version of the catalogue table.

     Via telnet to the BROWSE database system

        telnet ledas.star.le.ac.uk
        login: ledas
        
        browse roswfc2re
        ...
        exit
        ...
        lo

     Via WWW

Postscript and HTML versions of the paper (including the table and figures) can be viewed from the ROSAT-WFC EUV Survey home page (http://ledas-www.star.le.ac.uk/rosat_euv). The catalogue, roswfc2re, can also be browsed from the Web using the ARNIE system, available from URL http://ledas-www.star.le.ac.uk .

John Pye / Leicester University
E-mail (Internet): pye@star.le.ac.uk
27-Feb-1995

IRAF coordinate determination problem.

REMINDER:

There is a known inconsistency in how IRAF computes the pixel coordinates of images derived from blocked QPOE files. This bug has been reported to NOAO and appears as bug#6 in the list of known IRAF/PROS bugs (type "help bugs" once the x-ray package has been loaded). Here's the summary of it:

    6) IRAF/QPOE/IMAGE
    Class:  MODERATE
    Workaround:     YES
    Symptoms:       subtle

    There is a minor inconsistency between the QPOE and IMAGE coordinate
    systems.  Therefore we recommend that QPOE world coordinates NOT be
    calculated with routines such as RIMCURSOR and SKYPIX, but rather,
    with XEXAMINE, the only task that correctly supports these
    coordinates.  (The IRAF routines will lead to an error of up to
    one-half pixel, where the pixel size is dependent on the block factor.
    At block=1, there is no error.)

There is a brief discussion of this issue in PROS Hints & Pointers #4 & #5, and some more extensive background discussion (including figures) in the HEAO Newsletter vol. 1 No. 7, Sept. 1992. The problem apparently stems from an inconsistency in the definition of pixel values for the centers of pixels. IRAF, and later FITS, adopted integers, whereas the QPOE blocking routines (developed before the FITS standards were in place) used half-integers (the old Einstein convention). The bottom line is that CRPIX values of images derived from blocked QPOE files will be in error by up to 1/2 of a blocked pixel. There is no error in the WCS info of images made from unblocked QPOE files. Also, if one uses the x-ray task XEXAMINE", there is no error, since that task was specifically modified to fix the problem.

NOAO is aware of the problem, and it will be fixed in IRAF 2.11.

New ROSAT FTOOLS released.

Versions 3.3 of FTOOLS and 1.3 of XSELECT are now available. ROSAT highlights include:

     xy2sky - Transform from pixel to sky coordinates using WCS keywords

     sky2xy - Transform from sky to pixel coordinates using WCS keywords

 hrifilt   - Creates a ROSAT HRI makefilter file which allows user-defined
	     data screening within Xselect.

 hriexpmap - Creates exposure map for given ROSAT HRI observational dataset

 abc       - Apply Barycentric Corrections to ROSAT event data.

 bct       - Produce a Barycenter Correction Table from ROSAT orbit data.

 rosbary   - script to do ROSAT barycentric correction
             This runs abc and bct together.

 src2pha   - Creates a PHA file from specified extensions in an RDF
             src file. NOTE: There is a driver script to call this
             FTOOL, EXTPHA, type 'extpha' at your UNIX or DCL prompt
             and follow the directions.

<<<<<<<<<<<<<<<<<<<< SOFTWARE  RELEASE  ANNOUNCEMENT >>>>>>>>>>>>>>>>>>>>>>
                    ---------------------------------
<<<<<<<<<<<<<<<<<<< FTOOLS  VERSION 3.3  DISTRIBUTION >>>>>>>>>>>>>>>>>>>>>
<<<<<<<<<<<<<<<<<<< XSELECT VERSION 1.3  DISTRIBUTION >>>>>>>>>>>>>>>>>>>>>

How:    Anonymous FTP from heasarc.gsfc.nasa.gov
Where:  software/ftools/release/FTools_3.3 directory
What:   ******* FTOOLS Source and Data *******
        ***(get both unless you are only building "core" FTOOLS) ***
        ftools.v3.3.tar.Z   -  Source Code Distribution for all platforms
        refdata.v3.3.tar.Z  -  Minimal subset of Calibration Database

        *** Compressed Postscript Documentation ***
        ***(in software/ftools/release/doc directory)***
        Develop.v3.3.ps.Z    -  Developer's Guide
        Install.v3.3.ps.Z    -  Installation Guide
        Users.v3.3.ps.Z      -  User's Guide
        TechRef.v3.3.ps.Z    -  Complete User's Guide and help pages

        *** HTML Documentation ***
        at http://heasarc.gsfc.nasa.gov/docs/software/ftools/ftools_menu.html

Supported Platforms: (See Installation Guide for details)
        unix         ALPHA/OSF, DEC/ULTRIX, SUN/SunOS, SGI/IRIX
        vms          ALPHA/VMS, VAX/VMS

FTOOLS Version 3.3 Summary:

The FTOOLS have now been ported to Silicon Graphics workstations running IRIX. With the release of Perl5, most FTOOLS Perl scripts can be run on VMS machines (complete porting of all non-GUI scripts is planned).

New tasks available:

        abc - Apply Barycentric Corrections to ROSAT event data.
   ascaexpo - Generate an exposure map for an ASCA observation.
        bct - Produce a Barycenter Correction Table from ROSAT orbit data
        bkg - Subtract a background from a binned light curve
    col2img - Converts a collimator response dataset to an image
   fvec2img - Create an image from a column of vectors
  hriexpmap - Creates exposure map for given ROSAT HRI observational dataset
    hrifilt - Creates a ROSAT HRI makefilter file
    modalid - Print the space craft modal configuration (ASCA)
    perdgrm - Adds a sine curve and/or pulse-profile to a light curve. (XTE)
     sky2xy - Transform from sky to pixel coordinates using WCS keywords
    src2pha - Creates a PHA file from specified extensions in a ROSAT src file
     xy2sky - Transform from pixel to sky coordinates using WCS keywords

XSELECT version 1.3 summary:

 hrifilt   - Creates a ROSAT HRI makefilter file.
             The resultant makefilter file can be used to screen data
             using Xselect.

 hriexpmap - Creates exposure map for given ROSAT HRI observational dataset

 abc       - Apply Barycentric Corrections to ROSAT event data.

 bct       - Produce a Barycenter Correction Table from ROSAT orbit data.

 rosbary   - script to do ROSAT barycentric correction
             This runs abc and bct together.

 src2pha   - Creates a PHA file from specified extensions in an RDF
             src file. NOTE: There is a driver script to call this
             FTOOL, EXTPHA, type 'extpha' at your UNIX or DCL prompt
             and follow the directions.
 hiback    - Script to create a qsrc file from an src file.  It runs
             MKQSRC and adds a BKG_SUSP keyword to the output file as
             well.