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Catalogues to observation files

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rubyvanrooyen edited this page Aug 26, 2021 · 15 revisions

Observation catalogue

The minimum required information for any observation is a list of observation targets specified as one target per line, using comma separated formatting to provide the relevant target information.
Per target required information:
[name], tags, ra, dec or [name], tags, az, el
Details discussion of the per target information can be found on the Observation target specification page

The targets can be celestial or horizontal.
Specials such as TLE for satellites and near earth objects are not currently available.
Generally a catalogue is expected as part of the observation request.

Converting target catalogue to observation configuration file

If an observation catalogue file is provided, an initial configuration file can easily be generated. More extensive information on the observation configuration file can be found on the Observation file page.

The astrokat-catalogue2obsfile.py script does simple conversion of existing observation catalogues, CSV format, to configuration files, YAML format.

astrokat-catalogue2obsfile.py -h

usage: /Users/ruby/Projects/gitSDP/astrokat/venv/bin/astrokat-catalogue2obsfile.py [options] --infile <full_path/cat_file.csv>
...

The only required input parameter is the name of the catalogue file, --infile.
For convenience the YAML output will be displayed to screen if an output filename, --outfile, is not specified.
Once the user is satisfied with the output, an observation profile can be created
astrokat-catalogue2obsfile.py --infile targets.csv --outfile targets.yaml ...

For users familiar with the MeerKAT track.py or image.py observation scripts, the input to astrokat-catalogue2obsfile.py is similar to the standard options used by these to standard observation scripts.

/home/kat/katsdpscripts/observation/image.py <image.csv> --horizon=20 -t <target duration> -g <time on gain calibrator> -b <time on bandpass calibrator> -i <how often to visit bandpass calibrator> -m <total observation run time>

To create the associated YAML file from the standard observation options, the mapping of options between the two observation scripts are tabled below:

image.py astrokat-catalogue2obsfile.py
-t --target-duration
-m --max-duration
-g --secondary-cal-duration
-b --primary-cal-duration
-i --primary-cal-cadence

Adding observation source targets

Basic steps for conversion can be illustrated using some random targets, targets.csv

, radec target, 0:00:00, -90:00:00
, azel target, 10, 50
, gal target, -10, 40
Moon, special

Simple convert targets to configuration

astrokat-catalogue2obsfile.py --infile targets.csv --target-duration 10

Resulting in a basic target list

horizon: 20.0
observation_loop:
  - LST: 0:00-23:59
    target_list:
      - name=target0_radec, radec=0 -90, tags=target, duration=10.0
      - name=target1_azel, azel=10 50, tags=target, duration=10.0
      - name=target2_gal, gal=-10 40, tags=target, duration=10.0
      - name=Moon, special=special, tags=target, duration=10.0

No LST range was specified in the conversion, so a start LST for the targets have been inserted by default.
Target names were also not provided, resulting in generated names to be added.
Each target has its own tags and duration, which can be updated by the user.

The source list construction does not distinguish between targets and calibrators when converting from CSV format catalogues to observation files. When converting catalogues that contains calibrators, the user must specify the associated timings required.

astrokat-catalogue2obsfile.py --infile two_calib.csv --primary-cal-duration 180

horizon: 20
observation_loop:
  - LST: 12:30
    target_list:
      - name=1934-638, radec=19:39:25.03 -63:42:45.63, tags=bpcal, duration=180.0
      - name=0408-65, radec=04:08:20.38 -65:45:09.1, tags=bpcal, duration=180.0

In general the default application assumes gaincal as secondary calibrators, while bpcal, fluxcal and polcal targets are considered primary calibrators.

Similar XEphem targets can be represented in yaml format

astrokat-catalogue2obsfile.py --infile C_2002_Y1.csv --product c856M4k_n54M --target-duration 900 --max-duration 5400 --primary-cal-duration 300 --primary-cal-cadence 3600 --secondary-cal-duration 90 --outfile C_2002_Y1.yaml

> cat C_2002_Y1.yaml
# Observation catalogue for proposal ID None
# PI: None
# Contact details: None
instrument:
  product: c856M4k_n54M
durations:
  obs_duration: 5400.0
observation_loop:
  - LST: 20:46-16:47
    target_list:
      - name=C/2002 Y1 | C/2002 Y1 (Juels-Holvorcem), xephem=C/2002 Y1~e~103.7816~166.2194~128.8232~242.5695~0~0.9970576~0~4/13.2508/2003~1/01/2000~g6.5~4~0 , tags=solarsys target, duration=900.0
      - name=J0408-6545 | 0408-658, radec=4:08:20.38 -65:45:09.1, tags=bpcal fluxcal, duration=300.0, cadence=3600.0, model=(145.0 18000.0 -0.979 3.3662 -1.1216 0.0861)
      - name=J0906-6829 | 0906-682, radec=9:06:52.44 -68:29:39.8, tags=gaincal, duration=90.0, model=(145.0 20000.0 0.768 1.3416 -0.6601 0.0573)

Observations with targets and calibrators

Gain calibrators are generally intermingled with the source target list, with primary calibrators often need only be visited at some slower cadence.

# AR1 mosaic NGC641
# Catalogue needed for the AR1 mosaic tests
J1939-6342 | 1934-638, radec bpcal fluxcal, 19:39:25.05, -63:42:43.6, (408.0 8640.0 -30.77 26.49 -7.098 0.6053)
3C138, radec bpcal, 05:21:09.90, +16:38:22.1
J0155-4048 | 0153-410, radec gaincal, 1:55:37.06, -40:48:42.4
NGC641_02D02, radec target, 1:39:25.01, -42:14:49.2
NGC641_02D03, radec target, 1:40:36.77, -42:37:41.0
NGC641_02D04, radec target, 1:39:25.01, -43:00:32.8
NGC641_03D02, radec target, 1:37:01.49, -42:14:49.2
NGC641_03D03, radec target, 1:38:13.25, -42:37:41.0
NGC641_03D04, radec target, 1:37:01.49, -43:00:32.8
NGC641_04D03, radec target, 1:35:49.73, -42:37:41.0

Example of an imaging observation with both primary and secondary calibrators, where the bandpass calibrator is only observed every 30 minutes for 3 minutes. The targets for 5 minutes and the gain calibrators for 65 seconds.

astrokat-catalogue2obsfile.py --infile image.csv --target-duration 300 --max-duration 35400  --secondary-cal-duration 65 --primary-cal-duration 180 --primary-cal-cadence 1800 --outfile image.yaml

# AR1 mosaic NGC641
# Catalogue needed for the AR1 mosaic tests
durations:
  obs_duration: 35400.0
horizon: 20.0
observation_loop:
  - LST: 1:47-7:53
    target_list:
      - name=J1939-6342 | 1934-638, radec=19:39:25.05 -63:42:43.6, tags=bpcal fluxcal, duration=180.0, cadence=1800.0, model=(408.0 8640.0 -30.77 26.49 -7.098 0.6053)
      - name=3C138, radec=05:21:09.90 +16:38:22.1, tags=bpcal, duration=180.0, cadence=1800.0
      - name=J0155-4048 | 0153-410, radec=1:55:37.06 -40:48:42.4, tags=gaincal, duration=65.0
      - name=NGC641_02D02, radec=1:39:25.01 -42:14:49.2, tags=target, duration=300.0
      - name=NGC641_02D03, radec=1:40:36.77 -42:37:41.0, tags=target, duration=300.0
      - name=NGC641_02D04, radec=1:39:25.01 -43:00:32.8, tags=target, duration=300.0
      - name=NGC641_03D02, radec=1:37:01.49 -42:14:49.2, tags=target, duration=300.0
      - name=NGC641_03D03, radec=1:38:13.25 -42:37:41.0, tags=target, duration=300.0
      - name=NGC641_03D04, radec=1:37:01.49 -43:00:32.8, tags=target, duration=300.0
      - name=NGC641_04D03, radec=1:35:49.73 -42:37:41.0, tags=target, duration=300.0

The target and gain calibrator, without cadence values will be observed in sequence as listed in the catalogue. Thus, the YAML file must be edited to insert the gain calibrator in the observation sequence where needed.

# AR1 mosaic NGC641
# Catalogue needed for the AR1 mosaic tests
durations:
  obs_duration: 35400.0
horizon: 20.0
observation_loop:
  - LST: 1:47-7:53
    target_list:
      - name=J1939-6342 | 1934-638, radec=19:39:25.05 -63:42:43.6, tags=bpcal fluxcal, duration=180.0, cadence=1800.0, model=(408.0 8640.0 -30.77 26.49 -7.098 0.6053)
      - name=3C138, radec=05:21:09.90 +16:38:22.1, tags=bpcal, duration=180.0, cadence=1800.0
      - name=J0155-4048 | 0153-410, radec=1:55:37.06 -40:48:42.4, tags=gaincal, duration=65.0
      - name=NGC641_02D02, radec=1:39:25.01 -42:14:49.2, tags=target, duration=300.0
      - name=NGC641_02D03, radec=1:40:36.77 -42:37:41.0, tags=target, duration=300.0
      - name=J0155-4048 | 0153-410, radec=1:55:37.06 -40:48:42.4, tags=gaincal, duration=65.0
      - name=NGC641_02D04, radec=1:39:25.01 -43:00:32.8, tags=target, duration=300.0
      - name=NGC641_03D02, radec=1:37:01.49 -42:14:49.2, tags=target, duration=300.0
      - name=J0155-4048 | 0153-410, radec=1:55:37.06 -40:48:42.4, tags=gaincal, duration=65.0
      - name=NGC641_03D03, radec=1:38:13.25 -42:37:41.0, tags=target, duration=300.0
      - name=NGC641_03D04, radec=1:37:01.49 -43:00:32.8, tags=target, duration=300.0
      - name=NGC641_04D03, radec=1:35:49.73 -42:37:41.0, tags=target, duration=300.0
      - name=J0155-4048 | 0153-410, radec=1:55:37.06 -40:48:42.4, tags=gaincal, duration=65.0

Adding telescope specific requirements

Most astronomy observations will require a specific observation instrument, provided by MeerKAT as correlator products. These are generally identified from the science proposal requirements, but if known upfront, can be added in the conversion step.

astrokat-catalogue2obsfile.py --infile image.csv --product c856M4k --band l --integration-period 8 --target-duration 300 --max-duration 35400  --secondary-cal-duration 65 --primary-cal-duration 180 --primary-cal-cadence 1800 --outfile image.yaml

Which will add the following additional options to the YAML observation file

# AR1 mosaic NGC641
# Catalogue needed for the AR1 mosaic tests
instrument:
  product: c856M4k
  band: l
  integration_period: 8.0
durations:
  obs_duration: 35400.0
horizon: 20.0
observation_loop:
  - LST: 1:47-7:53
    target_list:
...

Table of Contents

Observation planning and setup

Input and planning utilities

Definitions and terminology

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