sci21068 — Announcement

On GMOS-S data affected by the CCD1 CTE problem.

July 14, 2021

It was recently reported that the observed counts in spectra seemed to be lower than expected on CCD1 for some programs - also, odd emission-like features (‘spikes’) were noticed in the CCD1 portion on stellar spectra that are known to be featureless.  All this applies only to data acquired during the ‘bad-CTE’ periods of CCD1, i.e. between:

  • 2020 Oct 24 - 2021 April 05
  • 2019 dec 18 - 2020 March 14
  • 2019 april 11 - 2019 June 24
  • 2018 May 14 - 2018 May 28 
  • 2018 april 15 - 2018 April 27

PIs with GMOS-S data observed during any of these periods are encouraged to assess whether this had a negative impact. PIs can look in the archive to identify the dates for which their data was taken at https://archive.gemini.edu/searchform/cols=CTOWEQ/notengineering/GMOS-S/NotFail/not_site_monitoring/progid=GS-20XYZ-Q-XXX 
(replace XY with the year and Z with the semester and the XXX with the program ID)

Currently, CCD1 is operating OK since the issue disappeared as of April 05, 2021.

About the Announcement

Id:
ID
sci21068