AIPS:  2004 Quarter 3

Key Developments

1.   Two new tasks to allow automatic editing were released in
relatively complete form.  FINDR applies various data averaging
algorithms to determine normal values and uncertainties in
baseline-based and antenna-based data values.  FLAGR uses similar
algorithms with user-supplied cutoff values to flag the data.
FLAGR also flags on out-of-range data weights.

2.   CLCOR was supplied with code to correct VLBA data for the
difference between gravitational bending of a source at infinity and
sources within the Solar System.  The new ephemeris routines used
provide accurate locations for the Sun and planets and were shown to
correct existing observations of NASA satellites to give extremely
accurate position information.

3.   The VLB astrometric task ATMCA that allows multiple calibration
sources to provide a more accurate calibration, fitting atmospheric
corrections, was enhanced with new modes.  It now handles observations
with only two calibration sources when the target source lies along
the line between them.  An AIPS Memo on the other atmospheric modeling
task DELZN was released.  It describes the choices which must be made
when planning high-accuracy experiments that will use DELZN.

4.   The master data sets used to test functioning and performance of
standard AIPS tasks were updated.  Changes in those tasks made the
previous master data sets inaccurate.  A HUGE test was added to handle
new, faster computers.

5.   The new calibration source models provided with AIPS pointed out
limitations in the modeling software which were corrected.  The faster
gridded modeling method is not accurate enough when very small images
are involved and so is suppressed in such cases.  Data weighted
inversely by the square of the uncertainty can lead to failures in
solutions for antenna gains.  User control over the weighting was
added to the calibration tasks.

6.   Miscellaneous changes included correcting the WENSS source
catalog lists to eliminate "sources" which are the sum of separate
components also appearing in the list, adding data computation display
options to the interactive editing tasks TVFLG and SPFLG, and changing
the method by which IMAGR chooses when to use the SDI method of
Cleaning.

7.   In the first three quarters of 2004, 175 sites downloaded the
31DEC03 (frozen) version of AIPS and 623 downloaded the 31DEC04
(development) version.  A total of 606 different sites (separate IP
addresses) made some use of the AIPS cvs facility, either during
installation of 31DEC04 or running the "midnight job" to update their
copy of 31DEC04.  Overall, 997 different IP addresses appear in these
three lists.


Goals for the Fourth Quarter 2004

1.   Continue user support and bug fixes, as the major portion of AIPS 
effort.  Prepare and start the new release and AIPSLetter in December.

2.   Test and implement binary distributions using the IBM Fortran
compiler for Mac OS/X computers.

3.   Provide support for pipeline data reduction, especially new
automatic editing algorithms.

4.   Begin investigations of new/improved imaging algorithms,
including those dealing with spectral index and multiple pointings.

5.   Begin to produce more source models to include with AIPS
distributions.