JCMT Software Newsletter Issue 2

The World-Wide-Web

The world-wide-web pages have not changed much since the last newsletter but remember that the JCMT software page and the unix support pages are there. An emacs1 help page is currently under construction and will eventually give information on some powerful features which you may find useful.

New JCMT software

Specx has undergone many improvements since the last newsletter to aid in raster mapping:

— INDEX-FILE and LIST-MAP now support ranges.

— DAS-MERGE is now a FORTRAN routine rather than a specx script.

— The READ-GSD-RASTER command has been added. This command will read in all the spectra in a multi-scan GSD file and copy them to a specx data file (with an optional DAS-MERGE).

— The MERGE-FILES command can merge two specx data files into one and will average spectra which are at the same offset.

It is hoped that these commands will make raster maps easier to deal with. (contact: RPT or TJ).

Standard is a new tool for searching the spectral line standards database. This program will show you how the strength of a given line has varied in the past. A WWW version has been created and is available2. (contact: LWA for standard and TJ for the WWW implementation).

Coadd has been ported to the unix systems and is now available (contact: TJ).

GSD access from perl is now possible. For small software tasks it is much easier to write in an interpreted language than a compiled one. For this reason a GSD module has now been developed so that perl scripts can access GSD data directly. For more information on this and an example please see the WWW documentation3 (contact: TJ).

Telescope control software

Just a reminder to Users about some recent on-line upgrades: the new catalog format, improved handling of source velocities and the ability to perform spectral line fivepoints.

Details about the new catalog format are available in the header of the standard catalog (JCMTDATA_DIR:POINT.DAT). It is now possible for the on-line system to read a source velocity from the catalog, and use this when configuring the frontend. Options are available to always apply the source velocity when slewing to a new source or to only apply the new value on demand (manual entry of velocities is available as before).

It is now also possible to perform five-points with the heterodyne receivers in spectral-line mode. The standard catalog contains a list of sources which have sufficiently strong lines that they are detectable in this mode; the fivepoint routine operates by using channels within the specified velocity range centred around the source velocity.

Tim Jenness, JCMT Software group

18th January 1996

1 = /user/emacs/

2 = /cgi-bin/standard.csh

3 = /software/utils/gsdmod.html