This users guide describes how to use the High Energy Astrophysics Science
Archive Research Center, HEASARC, Online Service. This service provides
remote online access to the HEASARC database tables, data files and
data analysis software. The emphasis is on browsing of the data, such
that users can make a quick-look display or analysis before exporting
it, or part of it, to their home sites.
Rather than invent yet another online system, the HEASARC has adopted an
existing system, the one developed for the EXOSAT mission by the European Space
Agency, ESA. This system is also in use at the University of Leicester in the
UK, the European Space Information System, ESIS, in Frascati, Italy, and at the
EXOSAT Observatory in ESTEC, Holland. While there is considerable overlap in
the data available at each site, there are differences which reflect local
interests and priorities in allocating disk space.
At the heart of the HEASARC Online System is the BROWSE program. This program is
being superceeded by thw W3Browse interface http://heasarc.gsfc.nasa.gov/W3Browse/
and by the AstroBrowse interface http://heasarc.gsfc.nasa.gov/ab/ . BROWSE provides
a command driven environment that allows a user to search one or more database
tables by coordinates, name, object class, or any valid parameter combination.
The selected data can then be displayed, extracted, and/or analyzed. The
analysis software available online is the XANADU (X-ray ANAlysis and Data
Utilities) which includes the following:
XSPEC - spectral fitting
XIMAGE - image display and analysis
XRONOS - timing analysis
QDP - plotting and function fitting
as well as SAOIMAGE, FTOOLS, and other useful
packages.
This user's guide concentrates on how to use the online service, in particular
the BROWSE program. The `Available Databases' guide, issued separately,
describes the data holding. There are separate user's guides for the XANADU
analysis programs including XSPEC, XIMAGE, XRONOS, and QDP. Other HEASARC
online services include ftp, gopher, and World Wide Web (WWW), and these are
outlined briefly here.
Problems with the system should be reported to Feeedback.
Be sure to include all relevant details. Suggestions for improvements are also
welcome and will be implemented when possible.
The database is designed to provide easy access to large volumes of
astrophysical data. Every effort has been made to validate the available data;
however, it is quite likely that there will exist problems with a small
fraction of the data contents. Users should contact the HEASARC, at the above
address if there are doubts regarding the correctness of the data.
