NEW GBI SCHEDULE FILE FORMAT
Revised 10 August 2000.
The new schedule file format is used for specifying observing schedules
for both the GBI and 85-3 telescopes.
Schedule files, or "obs" files, typically have names with a ".obs" extension,
although this is not required.
A list of schedule files to be observed sequentially or at specified dates
and times can be specified in a task file, which always must have a name
with a ".tsk" extension.
General rules for schedule files.
Files consist of ordinary ASCII text. Data fields are delimited by one or more blanks.
Lines may have up to 128 characters. There is no restriction on the number of
lines in a file.
Comment lines have one the following characters at the
beginning of the line: - * / # $
Keyword lines start with one of the keywords listed below.
In most cases the keyword is followed by a value. The remainder of the line
is ignored. Keyword values apply to the whole file, and they may appear
anywhere in the file.
Source Data lines give coordinates and stop times for the sources to be observed.
They are recognized by the first blank-delimited field NOT being any of the recognized
KEYWORDS, and not starting with any of the characters: - * / # $
Source Data lines must have at least 5 blank delimited fields: source name, RA, DEC,
Stop time, observing procedure; in that order. Additional fields are required by
some observing procedures. The default coordinate epoch is J2000.
Simple example for GBI observing.
----------------------------------------------------
EPOCH 1950.0
-- source RA DEC STOP GAIN
2030+407 20:30:37.6 40:47:12.8 21:00 g1111
1909+048 19:09:21.286 04:53:54.1 21:15 g0000
1915+105 19:12:49.97 10:51:26.8 21:30 g0000
2030+407 20:30:37.6 40:47:12.8 21:45 g1111
1915+105 19:12:49.97 10:51:26.8 22:00 g0000
----------------------------------------------------
The comment line describing the columns is optional.
If the "EPOCH" keyword line is omitted, J2000 is assumed.
Simple example for pulsar observing with telescope 85-3.
----------------------------------------------------
PULSAR
-- name RA(2000) DEC(2000) STOP(LST) PROC RCVR
0950+08 09:50:30.5 08:09:45.1 13:00:00 track
0950+08 09:50:30.5 08:09:45.1 13:30:00 track 327MHz
1937+21 19:37:28.7 21:28:01.4 15:40:00 track
1556-44 15:56:11.0 -44:30:16.9 16:00:00 track
1641-45 16:41:10.3 -45:53:38.7 16:30:00 track
1929+10 19:29:52.0 10:53:04.0 21:10:00 track
1937+21 19:37:28.7 21:28:01.4 23:10:00 track 327MHz
1937+21 19:37:28.7 21:28:01.4 00:05:00 track
-------------------------------------------------------
Here, the "PULSAR" keyword is needed so the 610MHz
receiver is the default.
Source Data Lines
Source data lines must have at least 5 blank delimited fields:
- Source name: up to 12 characters. If the name is a planet name (or Sun or Moon)
spelled with initial capital letter, the named planet will be tracked.
The RA and DEC fields will be ignored, but they must be present.
- Source right ascension (or HA if the hadec procedure is used): HH:MM:SS.SS
- Source declination: +/-DD:MM:SS.SS
- Stop time or duration: HH:MM:SS or HH:MM or HMMSS (duration).
The stop time is assumed to be LST, unless the keyword "TIME UT" appears,
in which case the stop time is taken to be UT.
- Observing procedure. The observing procedure names that may
appear are listed below. The "receiver" or "gain" parameters may appear
in this column, with the procedure name following or omitted. In this case,
if the procedure name is omitted, the "track" procedure will be used.
Some procedures (point, systempN, delaycal) require additional parameters
that immediately follow the procedure name.
Observing Procedures
These procedure keywords may appear as the 5th or later fields:
- track --Track specified RA/DEC position until stop time or for duration.
- tracal --Move to source position, do a system temperature calibration, then
track specified RA/DEC position.
- systemp --Do system temperature calibration.
- systempN A B C D --Set noise cal values for antenna N, then do system temperature calibration.
A=Tcal(SL), B=Tcal(SR), C=Tcal(XL), D=Tcal(XR)
- hadec --Move to specified HA and DEC. Use field 2 as the HA instead of RA.
- stow --Move all antennas to stow position.
- halt --Stop all antennas.
- quit --Stop all antennas, and quit running the schedule. When a 'quit' is encountered,
the schedule stops until restarted by an operator.
- delaycal corr step nsteps start --Do a delay calibration (search in delay for the maximum
correlation). corr=correlator name (1RS, 2RS, 1RX, 2RX, 1LS, 2LS, 1RX, 2RX).
step=step size in delay (units of 0.89ns); nsteps=number of steps in delay;
start=starting delay offset.
- point mode ant offset num Sband Xband --Do a pointing procedure.
- mode='S', 'F', or 'I'
- I : use interferometer mode, hold one antenna fixed while moving the other.
NOTE: "I" mode is not yet implemented.
- S : do pointing in single-dish mode, using total power detectors in the receiver.
- F : do on-off performance measurements only.
- ant = antenna number: 1, 2, 3 (or 0 for all)
- offset = position offset in each axis, in arcminutes.
- num = number of steps ('I' mode), or number of integrations ('S' mode)
- Sband, Xband = flux densities of this calibrator. If these are present,
system temperatures and efficiencies will be calculated.
- scan dRA dDEC vRA vDEC -- Scan source starting at specified offset (dRA,dDEC)
at specified velocity (vRA,vDEC). Single-dish total power data are stored
to a disk file. Units of (dRA, dDEC) are degrees of arc.
Units of (vRA, vDEC) are arcminutes per minute of time.
The following parameters may appear instead of, or in addition to, any of the procedures listed above:
- gABCD --Gain codes. A: SR, B: SL, C: XR, D: XL. Values of A, B, C, and D are 0, 1, or 2.
These mean: 0(max gain), 1(-10db), 2(-20db).
- receiver --Specify the receiver. Values are '327MHz', '610MHz', or 'SX'.
For GBI and VLBI modes, the default is 'SX'. For PULSAR and NOPULSAR, the default is '610MHz'.
Schedule file keywords
Lines starting with a keyword or keyword/value pair may appear anywhere in the file.
The order does not matter. These keywords will apply to the whole file.
Its probably best to put them all at the beginning of the file. If a keyword has a
value, that value follows the keyword after one or more blanks, for example:
EPOCH 1950.0
or
TIME UT
-mode- The mode keyword just appears by itself, with no value. It is one of the following words:
- GBI -- (default) GBI interferometer mode observing.
- VLBI -- VLBI mode observing -- (just in case we ever do this again).
- PULSAR -- pulsar observing with telescope 85-3.
- NOPULSAR -- using the 610/327 system on 85-3, but not for pulsar observing.
TIME -- The TIME keyword is followed by one of the two values: UT or LST:
- LST -- (default) The stop times in the schedule file are LST times.
- UT -- The stop times in the schedule file are UT times.
Note that the schedule file (at least so far) has no mention of the date. If a schedule file is to
run on a particular date, it must be specified in a task file.
EPOCH -- The EPOCH keyword is followed by the catalog epoch, such as 2000.0 or 1950.0
A2D -- The A2D keyword is followed by 6 numbers which are used to set up the data acquisiton
system for the GBI running in interferometric mode.
- sample rate -- (default=50 Hz) Samples per second -- Allowed values: 1 to 1000.
- integration -- (default=30 seconds) Length of integration over which fringes are fit, in seconds.
Allowed values: 1 to 100.
- gains -- (default= 1 1 1 1) List of 4 numbers of values 1, 2, 4, or 8;
being gain factors for SRR/SLL SRL/SLR, XRR/XLL, XRL/XLR respectively.
The A/D applies these gains after the usual GBI gain factors specified by the 'gABCD' parameter.
An example of the A2D keyword is:
A2D 100 20 1 2 1 2
Which means: sample rate is 100 Hz, integration period is 20 seconds, gain(SRR/SLL)=1,
gain(SRL/SLR)=2, gain(XRR/XLL)=1, gain(XRL/XLR)=2.
Task Files
The task file is a list of schedule files, and optionally start and stop date/times.
A task file must have a name ending in ".tsk"
Each line in a task file has three fields -- only the first is required.
You can put in comment lines that are ignored. Comment lines start with one of the characters:
- * # / $
The fields in a task file are:
- schedule file name -- Any valid file name (does not have to end in ".obs")
- starting date/time (optional) -- form: YYYYMonDD/HH:MM:SS or YYYYMonDD
- ending date/time (optional) -- form: YYYYMonDD/HH:MM:SS or YYYYMonDD
If the time (HH:MM:SS) is omitted from the date/time parameter, it will be assumed
to be 00:00:00 on the starting date, and 23:59:59 on the ending date.
If the ending date is omitted, it is assumed to be past any other ending dates.
The starting date/time will pre-empt whatever is running.
Any schedules that have no dates will just be run in the order they appear in the list,
after the schedules with dates have been completed.
When a task file is completed, and if there are schedules without dates, the non-dated
schedules will be repeated.
Example of a task file:
----------------------------------------------------------
NASA.SKD.A
NASA.SKD.B
NASA.SKD.C 2000Jun23/18:00:00
NASA.SKD.D 2000Jun24/02:00:00 2000Jun24/20:05:00
----------------------------------------------------------
In this case, if the task file is started on June 22nd, it will start with
schedule "NASA.SKD.A", then go on the NASA.SKD.B.
When 18UT on June 23 comes around, NASA.SKD.C will start.
If it is still running at 02UT on June 24, then NASA.SKD.D will
interrupt and run until its stop time of 20:05 UT.
Then the task file will be repeated starting at the first line,
NASA.SKD.A, and going on to NASA.SKD.B.
NASA.SKD.C and NASA.SKD.D will not be repeated.
fghigo@nrao.edu last changed this page 10 August 2000.