Weekly Checklist of Astronomers of Duty

This is page http://www.iram.es/IRAMES/mainWiki/AstronomerOfDutyChecklist maintained by CK.
Intended Audience: IRAM staff astronomers

Schedules: AoDs, Operators, Projects

News from 13-Jan-2012 CK

• The EMIR homepage is constantly updated to reflect the current status.

• 32GHz FTS

  1. 200kHz <-> 50kHz:Switching between 200kHz and 50kHz resolution needs some manual interaction by the operator. It is not yet automatized!

  2. Attenuators: After starting a project, retuning the receivers, or switching between 200kHz and 50kHz, the operator needs to readjust the attenuators on the ambient load in order not to saturate the FTS. The operators have a detailed guideline on their wiki. The AoDs should check at the beginning of observations that FTS data are actually produced. It happens that no data are produced and the fts process on the fts pc needs to be restarted by the operator.

  3. Restarting the FTS process will also re-calibrate the FTS-ADCs. It is a good idea to do this at least at the start of each project on a given day.

  4. HERA: When using 50kHz with HERA, switch to fine mode to place the line in the center of the band.

  5. Dump times: AoDs should keep an eye on the dumping times, especially when the observer uses on-the-fly or frequency switching. Dumping times down to 500msec-100msec work (with the fully optimized mira version installed in the last week of July), but will create huge amounts of data in a short time! Keep an eye on disk space. Check with the observers that they rsync their data to their external USB disks, if possible.

  6. Frequency shifts: After correcting for two bugs in mira and class in July-2011, we put a report (Buchbender et al.) onto the EMIR homepage.

• bbc/nbc
  1. At present, a calibration needs to be done with bbc, as odp is not yet able to show raw data.
  2. bbc can only be used for EMIR. It is not available for HERA.
  3. The use of the new wide band continuum backend bbc is encouraged for standard pointing and focussing.
  4. For accurate flux measurements, it is yet safer to use the old nbc backends.
• Known problems:
  1. The fts-process stops from time to time. There is no warning. No data are produced.

At the beginning of the AoD week

• Make yourself familiar with the present system status by reading the status page, previous reports, and by asking staff, in particular also Juan Penalver. Which backends are available ? Had there been receiver related problems lately ? When was the last pointing session ?

• Check the observing schedule. If there are any TBD intervals, please contact Nicolas Billot or Clemens Thum or the station manager to clarify their usage.

• Please check with the observers whether they will use the FTS and with which dumping times. Please inform the computer group in case of dump times of less than 500msec.

• Do test observations near the end of the Tuesday maintenance period (T00-09): Ask operator to execute ./goOnce and ./go then let the operators tune to the frequencies of the following project. Do a quick calibration and pointing. Connect some spectrometers and do a quick position switched test observation (onoff). Use a strong line calibrator (e.g. from the Mauersberger catalogue) for this. Test the band combinations used by the next project. Beware that during one hour, only a brief test of the basic functionality can be done.

• Please also check with the local staff doing the weekly maintenance
  1. any changes made to the system which may affect observations, and

  2. whether it is possible to start the T00 test observations early on. If possible, i.e. if it fits with the maintenance work, the Astronomers of Duty should start testing as early as 3:30pm, using the setup of the next observing project.

During the week

• Speak with the observers and operators to check and discuss any problems. Do not hesitate to contact other staff.

• Help the operators with the heterodyne tests while the telescope has to stay in stow position. These are described here.

• Remind the observers to check the frequency tuning by observing a line calibrator with strong and known lines (e.g. DR21, W3OH, OriIrc2, etc.).

• Get an idea of the pointing situation by speaking with the observers or checking TAPAS.
  • How large are the observed offsets ?

  • Are pointing & focus affected by anomalous refraction ?

  • In case of large pointing jumps:
    • If the jump is only in elevation, check that the relative humidity is read from the weather station. This is used to calculate the refraction correction. In case the humidity sensor is covered by ice and stuck at 100% humidity, the operators can use a handheld hygrometer and enter the value by hand in manual mode.

    • Check that the pointing constants p4/p5 do not show jumps here. These may indicate problems of the inclinometers.

  • Summarize the pointing situation in your AoD report. Do not only include only plots, but say whether or not there are problems. Remember that pointing offsets are not important, but their scatter. Attach a small selection of plots showing the pointing and focus corrections observed during the week by using TAPAS and the script developed by CB.

• Update the status page.

• Take a look at the cable spiral, telescope tower, and receiver cabin at least once during the AoD week.
• During the week, measure the time it takes to start a scan and to do a calibration. See the AoD report of CB of 10-Jan-2012.
  • select a source that is close to elevation 45 degrees (in the elevation range 30 to 60 degrees.)
  • in pako enter:
    • CALIBRATE /DEFAULT
    • START
    • START
    • (or more starts if you have time)
  • ignore the times from the scan after the first START, because they may include additional overheads, e.g., to move the antenna to the start position

  • read the times from the displays of the messages, e.g., in the top center panel of https://mrt-lx1.iram.es/mrt/ncs/monitor/scanInfo.html or in the antennaDataStreamViewer

  • for the time to start, record the time interval form the message "scan loaded" to the message "calSky started"
  • for the time to execute the scan, record the time from the message "calSky started" to the message "scan done"

• The weekly report to be send at the end of each AoD week, should address the following topics. Please add eps files to your report, to better explain any problematic spectra, etc.. Better start writing the report already on the first day of the AoD week, and not at the very last moment. Report what is not working, but also changes to the positive. There is no need to repeat any daily operator reports. The report shall be send to aodreportlist AT iram.es and should be structured as follows:

  1. Pointing/Focus

  2. Receiver

  3. Backend

  4. Computers

  5. Software/Documentation

  6. Scheduled projects (T00, other technical projecxts (TT), Astronomy)

  7. Other remarks

• The above list assumes that you are familiar with the system:
  • Computers, Printers
  • Basic working of pako, odp/mira, class, greg
  • Basic security rules (Operators, Juan)
  • Observatory information for the guest observers
  • Basic IRAM web pages, wikis.

  • See the AoD Training Checklist maintained by Manolo

  • See the NCS Operations Notes maintained by Hans