LOG & CALIBRATION FILES

Regardless of the recording format used, the following machine-readable files record events and conditions during a VLBI program:

1. An ASCII VLA operator's log, usually called ``bbbbblog.y'', where ``bbbbb'' is the project code (e.g., bq001).

2. An ASCII VLA calibration file. The VLA's Modcomp computers log information about events under their control and enter both weather and calibration data into a calibration file. The VLA calibration file is called ``bbbbbcal.y'', where ``bbbbb'' is the program code (e.g., bq001). Section 10 discusses the content of a VLA calibration file.

3. A binary VME file. The VLA's VME computer logs information about events under its control into a binary file, the contents of which are entered into a database read directly by the VLBA correlator. An ASCII file, usually called ``bbbbbcal.vlba'', where ``bbbbb'' is the program code (e.g., bq001), can also be formed from this database.

Upon completion of a VLBI program, VLA Operations will send the recorded VLBI tapes to the designated processor. VLA Operations will also e-mail the VLA operator's log to the observer. The VLA operator's log plus the VLA and VLBA calibration files will be deposited in subdirectory /home/aspen6/astronomy/mmmyy/bbbbb on the Sun workstation called aspen at the AOC. Here, ``mmmyy'' is a code for the month and year (e.g., apr02) of program with code ``bbbbb'' (e.g., bq001). Instructions on how to access AOC workstation aspen are available from the VLBA astronomer's page.