Execution Block ID uid://A001/X15a0/Xd2 Sgr_A_st_i_03_7M

keflavich commented 2 years ago

Sgr_A_st_i_03_7M uid://A001/X15a0/Xd2

[x] Observations completed?
[x] Delivered?
[x] Downloaded? (specify where)
- [x] hipergator
- [x] hipergator pipeline run
- Pipeline Run 20230224T051037
- Pipeline Run 20230224T050312
- Pipeline Run 20220413T133858
- Pipeline Run 20220411T163036
- Pipeline Run 20220411T163903
[x] Weblog unpacked
[ ] Weblog Quality Assessment?
[ ] Imaging: Continuum
[ ] Imaging: Lines
- [ ] HCO+
- [ ] HNCO
- [ ] H13CN
- [ ] H13CO+/SiO
- [ ] Cont 1
- [ ] Cont 2

Product Links:

Reprocessed Product Links:

xinglunju commented 2 years ago

We will use this one for (offline) training at SHAO

xinglunju commented 2 years ago

Quick comments: spectral lines in spw 20 & 22 are found on (or out of) the edges of the windows. See snapshots below. There is an SB named 'Sgr_A_st_i_updated_03_7M' in the queue. Does that one have the corrected Vlsr? The 12m array SB 'Sgr_A_st_i_03_TM1' has been completed. Not sure if it uses the correct Vlsr or not.

uid___A001_X15a0_Xd2 s31_0 Sgr_A_star_sci spw20 mfs I findcont residual onlyExtraMaskIntersect meanSpectrum mom0mom8jointMask min min 2 56sigma narrow4 trimauto_max=0 1 overwriteTrue

keflavich commented 2 years ago

@xinglunju could you have a look at the continuum identification in the H40a band (I think it's the broad-band window)? In the peak intensity map, this whole field shows up as too-bright, which suggests to me that the continuum is nonzero:

Alternatively, it might not be the continuum, it might be one bright / poorly behaved channel; if it were continuum, I'd expect to see a problem in the moment-0 map, but I do not see that.

xinglunju commented 2 years ago

I took a quick look at the cube of spw24. Overall, most of the spectra look good, with a baseline level at ~zero. Toward the northwestern part, around the Sgr B2 hot cores, the baseline levels are above zero, but only in a small region, not the whole field.

I guess it is because the image rms is much higher than requested. The measured rms is ~0.1 Jy/beam, while for all the other 7m SBs the rms of this spw is 0.02-0.03 Jy/beam. So this SB should have been marked as QA2 fail, but we should wait for the other SB 'Sgr_A_st_i_updated_03_7M' that has the correct Vlsr anyway...

xinglunju commented 2 years ago

Overview

This SB is used for weblog review training, and probably should not be used for science: it seems to have incorrect Vlsr, and should be replaced with another SB named 'Sgr_A_st_i_updated_03_7M'. Nonetheless, we found the following issues.

Calibration summary

Task 13. Bandpass calibration
- There is an error--QA Lowest score for phase derivative is 0.19 (uid___A002_Xf4df6f_X484c.ms CM12 spw 22 XX).
- Visual inspection suggests that XX polarization of spw22 of CM12 does show a large scatter in bandpass. However, the other spws or antennas do not seem any better.
Probably related to the previous error, the fourth epoch of phase calibration was flagged:
- Comparing tasks 12 and 15: 21.8% flagged vs. 41.5% flagged for the phase calibrator, suggesting that additional ~20% data were flagged somewhere between the two steps, very likely in task 13.
- As a result, the last epoch of observations on target cannot be calibrated, and was flagged (~1/3 of all on-source time). In total almost half of the on-source time was flagged (see next point).
Task 19. Apply calibration tables
- Warning (as expected): For uid___A002_Xf4df6f_X484c.ms, intent(s): TARGET, 25.78% of the data was newly flagged by applycal flagging agents, for a total of 47.63% flagged.

Imaging summary

Task 31. Find Continuum
- Too few channels are considered as line-free in spw 26.
- For all the spws, the continuum selection could be improved, e.g., by separating the pointings on the NW corner where sgr b2 hot cores are detected and the other pointings, and using two findcont strategies.
Continuum imaging (Task 34. Tclean/MakeImages/36. Tclean/MakeImages)
- Imaging is dynamic range limited, which is expected considering the presence of the sgr b2 hot cores. Achieved rms is ~2.5 times higher than the theoretic value.
- Aggregate bandwidth only 0.745 GHz--Better findcont strategy to get broader bandwidth is needed, especially for Sgr B2 regions.
Line imaging (38. Tclean/MakeImages) Overall the line images are good (not dynamic range limited), except that the rms is much lower than requested in the proposal--too much data flagged and only one EB in this SB. Other SBs typically have 5 EBs.

d-l-walker commented 2 years ago

Thanks for the detailed summary @xinglunju! Regarding your last point, yes this SB only had one execution and subsequent EBs were cancelled due to the incorrect spectral setup. The execution fraction is 0.2/8.0, so it makes sense that the RMS is not good enough.

xinglunju commented 2 years ago

This SB is not supposed to be used for science. Should I close this issue? @keflavich

keflavich commented 2 years ago

Yes, we can close this and ignore this SB in the future.

keflavich commented 1 year ago

The pipeline re-ran on this field last night. I am not sure why; my best guess is I made a typo and removed this one (Xd2) instead of an adjacent MOUS name (https://github.com/ACES-CMZ/reduction_ACES/issues/247, for example, is Xb2).

ACES-CMZ / reduction_ACES