This page contains reports about data issues, and links to SRDP JIRA tickets describing oddities in VLA datasets that DAs and AoDs should look for repeats of to report to Ops meetings.
For reporting, please include information about band, configuration, whether it persists, and name of data set or sets.
Data to be held for discussion and inspection can be copied to:
/lustre/aoc/projects/srdp/problem_data/
Amy Kimball (Nov 9, 2022) : we can start shifting over to reporting and tracking issues in https://bugs.nrao.edu/projects/VLASTS If you do not have access, send CIS HelpDesk ticket to request access.
Data sets to annotate in the archive (once that functionality is available):
22A-216 and 20A-160: pipeline hacks to ignore requantizer table
New Reports
ea28 R polzn seen in SysPower Pdiff started noticing in 4/2023
ea27 in SysPower Pdiff, variable Pdiff values in time 4/2023
ea03 R polzn, mostly on B0D0 L band gain amps and phases in some data
Ongoing
- ea16 L polzn. (https://bugs.nrao.edu/projects/VLASTS/issues/VLASTS-5) gain amps/phases in some data stiill present. Action: Paul Demorest to follow-up with team (looks like loose cable) (1/4/23)
- Tracking purposes: 22B-174, RSRO solar project, longer SBs don't produce MS (slicer error), discuss. CAS-14007 - Getting issue details... STATUS
Resolved
- C band compression ← Pedro Beaklini looked into this and going forward we will offer 3-bit/8-bit hybrid correlator setups for each configuration, with users encouraged to make use of them.
- S-band, A0C0, LL correlation issue. (AL) <--- this was seen only once. Moved to "resolved" as of 1/25/23
- T304-C replaced 12/21: ea14 dropouts (https://bugs.nrao.edu/browse/VLASTS-4)
- ea26 DTS(?) A1C1 - fixed 7/28? - operator log says parked for ongoing issues 8/02 (DM: last seen 2022.10.19 so far, seems fixed late Oct.)
- ea01 C band AC - https://bugs.nrao.edu/browse/WO-14498
- ea10 or ea11 often have one spw with high delays - BlB restart fixed July 6
- ea04 3-bit/A1C1 - BlB restart fixed July 6
- ea21 B0D0 gain amps low/vary in time L band - resolved? (1/4/23)
- ea04 A0C0 ~42ns delays one polzn. - resolved? (1/4/23)
- MODEL ISSUE:
SRDP-549
-
Getting issue details...
STATUS
Also in X band: 22A-384_2022_03_29_T23_25_28.051
/lustre/aoc/projects/srdp/problem_data/west_arm_ramps/ ← not intrinsic data issue
- 2022-06-17: ea03 bandswitch issue (stuck in X band), reported fixed July 13
- ea14 ANOS flags > uses 0.3s threshold, other antennas use 1s. ACUs possibly being updated to 0.3s in future
- ea17 "switch"
- Weather station down
- ea10 AC phase
- ea17 BP amp
- ea28 L band polarizer Feb 26 - Mar 17, 2022
Probably resolved by magic
- ea16 L pol
A band issues approximately 2021.10.01 - 2021.10.16: ea12 (B1D1,B2D2), ea22 (B2D2), ea28 (B1D1,B2D2). Last good example is 21B-266.sb40061479.eb40729137.59503.1225524537.
- ea10 Q band (switch?)
- scatter at 2 GHz intervals SRDP-548 - Getting issue details... STATUS
- ea06 shows amplitude fluctuations in K-band SRDP-550 - Getting issue details... STATUS
- A config outer antenna amplitude ramps in C-band: esp: ea15, ea26 - if a resolved flux calibrator starts the observation, the amplitude correction is a strong function of frequency and changes when the observation moves to an unresolved calibrator. SRDP-549 - Getting issue details... STATUS
No calibration issues, so no plan to fix
- ea11 16 ns delay offsets in some basebands, does not cause calibration problems
- ea14, ea16 X-band delay 16ns split between polarizations
- ea23 BP ← not a problem; this calibrates out
- 22A-111_2022_04_01_T12_37_31.953: C-band, 3-bit, 3C286 Flux/BP cal. Pipeline flagged a time range at the beginning of the Flux/BP scan, but mysteriously left in a random spw during this time for some antennas in the lower baseband (A1C1). This created an odd looking feature/spike in the initial Amp vs Freq plots in the first hifv_checkflag stage. Spw 17 was affected for the initial pipeline run for this SB and was manually flagged in full. This occurred again in a subsequent run, specifically spw 24, after a flag was added for an unrelated issue on antenna ea02 - spw='28:44~60.' The solution was to flag the time range in full for all spws. The flagging for spw 17 was removed and the data looks okay. The cause remains unknown.