VLA Archive file 22B-193.sb42955338.eb42982659.59891.82213731481

[eacmills]

SB 42955338 JACKS region 1

• [x] Observations completed
• [x] VLA CASA Calibration pipeline run by observatory
• [x] Weblog downloaded and unpacked
• [ ] Raw data downloaded (specify where)
  • [ ] local machine
  • [ ] Globus
• [ ] Pipeline calibration assessment
• [ ] Calibrated MS generated
  • [ ] Uploaded to Globus
• [ ] Imaging: Continuum
• [ ] Imaging: Lines
  • [ ] NH3 (1,1)
  • [ ] NH3 (2,2)
  • [ ] NH3 (3,3)
  • [ ] NH3 (4,4)
  • [ ] NH3 (5,5)
  • [ ] H2O
  • [ ] H64
  • [ ] H66
  • [ ] NH3 (2,1)
  • [ ] NH3 (3,2)
  • [ ] NH3 (4,3)
  • [ ] NH3 (5,4)
  • [ ] NH3 (6,5)

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[eacmills]

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Log Name: 2022-11-08_1943_22B-193 Project: 22B-193 SBID(s): 42955338 EBID(s): 42982659 Observing Date: 08-Nov-2022 Observation Type: Science Bands Used: X K No. Subarrays: 1 Observer(PI): Prof Elisabeth Mills Source File(s): 22B-193_sb42955338_1_1 Operator(s): Kenneth Gibson and Katie Grabowski Array Configuration: C Decommissioned Antenna: 20

Adobe PDF version of this log is located at: http://www.vla.nrao.edu/operators/logs/

WEATHER INFORMATION

Time(UTC) Dew Pt Temp Wind Bar Press API RMS Phase(degs) 08Nov 19:45:02 -7.8 17.3 SW at 5.9 m/s 788.5 6.6 08Nov 22:00:13 -10.1 18.4 SW at 9.5 m/s 787.7 13.9

Operator comments for the above weather entries

08Nov 19:45:02 Sky clear.
08Nov 22:00:13 Sky clear.

COMMENTS AND OUTAGES

Outage information format: Start Time, End Time, Category, Form#, # Antennas, Down Time(minutes) Antenna ID(s) and Data Effect Description

Number of Antennas Used: 27

08Nov 19:43:51 Starting project 22B-193.

08Nov 19:43:51 The band(s) used is(are): X K.

08Nov 19:43:52 On source 3C286 with all available antennas.

08Nov 19:43:51 To access your data from the NRAO archive visit: https://science.nrao.edu/facilities/vla/archive All VLA science data are processed through the VLA calibration pipeline. Details are at: https://science.nrao.edu/facilities/vla/data-processing/pipeline For further questions please use the NRAO Helpdesk at: https://science.nrao.edu/observing/helpdesk Adobe PDF version of this log is located at: http://www.vla.nrao.edu/operators/logs/

08Nov 19:43:51 Note: To support our ongoing RFI monitoring efforts, any feedback from your program on RFI can be sent to: nrao-rfi@nrao.edu The key information to provide is:

• Observation/project code
• Frequency and Time of the observations
• The characteristics of the RFI signal, in particular if it is continuous or intermittent?
• If possible, a spectrum of the RFI should be included in the e-mail. Thanks very much for your support; this information will be continuously updated on the EVLA science pages at: https://science.nrao.edu/facilities/vla/docs/manuals/obsguide/modes/rfi/

08Nov 19:43:51 08Nov 23:13:17 LO-IF WO-15042 0.03 6.0 Antenna(s) 12 (Data: Corrupted): IFA0 weak in X-band, possible T304 issue.

08Nov 19:43:51 Antennas in the C-array may be shadowed at low elevations. If shadowing occurs, sensitivity will be affected.

08Nov 22:55:00 Your new operator(s) is(are): Hannah Brower

Project End Time Total Time % Down Time Total Down Time (minutes x 27 ants) (minutes)

08-Nov-2022 23:13:17 5654.7 0.1% 6.0

[eacmills]

• Issues noted but not flagged by staff in pipeline run:

  Wind speeds and API above limit for K band for entire observation. ea07 - hardware issue on A0C0 rignt polzn ea04 - drop in gain amplitudes on scan=35 phase jumps lower structure on the corr. amp. vs uvwave plot for the complex gain calibrator is on most scans and due to wind/phases, strongest on scan=8,10,12,16,18,20,31,33,35,39,42,46,48,50,59

[d-l-walker]

A couple of issues with this one, which are related to the points that Betsy noted above. I think these can just be flagged when reprocessing?

It's also noted that the wind speed is above the limit for the whole observation. Is this something we need to worry about? It's noted that there are phase jumps and issues with the gain calibrator as a result of the wind ...

Offsets in gain amp on ea07 -- I guess related to the hardware issue noted by the staff?

Slight drop in gain amp at ~ 21:25 on ea04

[d-l-walker]

Some more issues noted during our discussion today:

Significant phase jumps on all antennas likely due to weather conditions, e.g.

As noted by operator, signs of decorrelation, again likely due to high wind speeds

The flux of the phase calibrator is also ~ 7% lower than expected.

The next steps are to download the data, re-run the PL with additional flags, and then try to image the continuum. We'll then assess the quality/RMS of the continuum image, and determine whether we need to go back to the observatory to get this reobserved.

[d-l-walker]

Data downloaded and calibration pipeline is now running. Once completed, I'll try imaging the continuum to assess the quality.

[d-l-walker]

Here's a comparison between the continuum for field 1 (left) vs. the ACES+GBT continuum (right). Clearly tracing the same single continuum source, but the artifacts are quite prominent. The RMS of the continuum is ~ 25 uJy.