Starlink SPLAT-VO released

[Peter W. Draper]

                         Announcing Starlink SPLAT-VO
                         ============================

The Starlink Spectral Analysis Tool (SPLAT) has been upgraded to include a
demonstration toolbox for querying, downloading and displaying spectra
from simple SSAP servers.

It is available as a download for installing onto your desktop or as a
Java webstart application for Linux (RH9+), Windows (XP), Mac OS X (10.3)  
and Solaris (8+) at:

   http://star-www.dur.ac.uk/~pdraper/splat/splat-vo

SPLAT-VO is part of the Starlink STARJAVA package and is available under the
GPL.

Highlights of this release, besides being able to make SSAP queries, are
the matching of spectral coordinates and fluxes between spectra. Spectral
coordinates include the full range described in FITS WCS Paper III, that
is wavelength, frequency, energy and velocity etc. These can be described
in various rest frames -- topocentric, heliocentric, dynamic and kinematic
local -- and can be transformed between them all.

Differences between data value units can be automatically taken account of
when overlaying spectra as long as the units strings conform to the system
described in FITS WCS paper I. Also, automatic identification and
conversion between flux per unit wavelength and flux per unit frequency is
provided and does not require any "dimensional analysis" information to be
present

These two systems will be extended to include others such as magnitude and
antenna temperature that require additional meta-data to fully describe
the inter-system transformations. All coordinate and flux transformations
are handled by the Starlink AST package, developed by Rodney Warren-Smith
and David Berry (dsb at ast.man.ac.uk). AST also provides the plotting
facilities used for drawing spectra in SPLAT-VO.

Naturally such an early implementation has many limitations -- the server
list is currently fixed (not for long), the queries only use the basic set
of parameters (position and radius) and the returned spectra may only be
simple FITS or VOTables, but it is hoped to be of some use.

Cheers,

Peter.

--
Dr. Peter W. Draper, Starlink Programmer,    http://star-www.dur.ac.uk/~pdraper