Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Execution Block ID uid://A001/X15a0/Xd2 Sgr_A_st_i_03_7M #37

Closed
6 of 15 tasks
keflavich opened this issue Jan 10, 2022 · 9 comments
Closed
6 of 15 tasks

Execution Block ID uid://A001/X15a0/Xd2 Sgr_A_st_i_03_7M #37

keflavich opened this issue Jan 10, 2022 · 9 comments
Assignees
Labels
7m Delivered EB Execution Block

Comments

@keflavich
Copy link
Contributor

keflavich commented Jan 10, 2022

Sgr_A_st_i_03_7M
uid://A001/X15a0/Xd2

Product Links:

Reprocessed Product Links:

@keflavich keflavich added 7m EB Execution Block labels Jan 10, 2022
@xinglunju xinglunju self-assigned this May 18, 2022
@xinglunju
Copy link
Contributor

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

@xinglunju
Copy link
Contributor

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
uid___A001_X15a0_Xd2 s31_0 Sgr_A_star_sci spw22 mfs I findcont residual amendedMask meanSpectrum amendedJointMask min min 2 50sigma narrow4 trimauto_max=20 overwriteTrue

@keflavich
Copy link
Contributor Author

keflavich commented Jun 3, 2022

@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:

image

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
Copy link
Contributor

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
Copy link
Contributor

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
Copy link
Contributor

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
Copy link
Contributor

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

@keflavich
Copy link
Contributor Author

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

@keflavich
Copy link
Contributor Author

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 (#247, for example, is Xb2).

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
7m Delivered EB Execution Block
Projects
None yet
Development

No branches or pull requests

3 participants