AIPS: 4th Quarter 2002

Distribution and Versions

              The 31DEC02 version of AIPS was frozen in late December, and the frozen version now is available for download. The new test version, 31DEC03, was started and now is available via the standard midnight job. Unfortunately, the lack of systems support for AIPS has prevented the re-institution of monitoring of ftp downloads of the frozen version, though it is known that over 50 different sites are running the midnight job.

Key Developments

1.           A major multi-task development has been the institution of full color-plotting capabilities in AIPS. The standard contouring tasks such as KNTR, GREYS, and PCNTR can produce grey-scale images that can be converted to pseudo-color or to standard true-color (rgb) images with a color table (OFM, or “output-function-memory”). The standard plotting task, LWPLA, has various levels of control enabling the specification of the conversion from grey-scale to color scales. Based on user specifications, contouring, labeling, and polarization vectors can change “automatically” between light and dark colors based on the brightness of the underlying background. In addition to the rgb (red-green-blue) color representation, a cmyk (cyan-magenta-yellow-black) capability also exists, which enables the direct production of color postscript files that can be used directly by many of the standard research journals.

2.           The VLBA data reduction pipeline, previously called as a stand-alone script, now has been incorporated into the standard AIPS release, and is included both in the frozen version of 31DEC02 and the updated version 31DEC03.

3.           The UVCON task used to simulate (u,v) data has been given additional capabilities in order to support configuration studies for the VLA Expansion Project. The simulation of random phases added by RFI sources in antenna sidelobes now is possible, and large-angle data shifts can be made.

4.           For a number of years, definition of a new “World Coordinate System” (WCS) standard has been sought under the auspices of both international and national FITS working groups, with major participation and leadership from within the AIPS group. This standard is critical for the ultimate goal of full data specification and interchange under the auspices of the planned National Virtual Observatory. We are pleased to report that the WCS standard has been approved by a vote of the appropriate FITS working groups, and the two papers defining the basic WCS specifications now have been published in Astronomy & Astrophysics.

5.           A number of changes were made to the installation procedures for AIPS, to make it more robust for the many users and maintainers of AIPS at remote installations.

6.           A new task, LOCIT, was added to enable the data analysts to fit for antenna positions after VLA reconfigurations.

7.           The planned guide to low-frequency imaging depends on postdoctoral fellows, one of whom has finished the postdoctoral appointment. This item is still on the target /“hope” list.

Goals for First Quarter 2003

1.           Continue user support and bug fixes, as the major portion of AIPS effort.

2.           Add monitoring of ftp downloads of frozen AIPS version (delayed from previous reports due to lack of systems support).

3.           Port AIPS to McIntosh OSX operating system

4.           Upgrade smoothing and blanking methods in SNSMO, CLCAL, and related tasks.

5.           Complete low-frequency/wide-field cookbook appendix.