The Project Commissioning team welcomes input from the Rubin science community regarding considerations for the on-sky observing strategy during commissioning that would enhance opportunities for science validation studies. As discussed at the PCW 2020, this is a “shared risk” or “best effort” situation in which input from the community will be taken into consideration alongside Project needs to perform technical and scientific verification of the formal system requirements to demonstrate construction completeness. The detailed schedule of on-sky observing periods during commissioning is still to be determined, and the Project cannot ensure that any particular observations will be taken during commissioning. The Project Commissioning Team has already been planning to acquire on-sky observations that would enable science validation studies for the four main science drivers of the LSST. Additional input from the community will be valuable to further develop these plans. The Project Commissioning team will also be in regular contact with the Survey Cadence Optimization Committee and Operations Team.
The Project is particularly interested in collecting observations that would help to (1) demonstrate the scientific capability of the as-built system and (2) inform early operations of the LSST.
We anticipate at least two phases of collecting community input.
To provide guidance for the on-sky observing strategy during commissioning, the community are encouraged to produce summary documents, “commissioning notes”, that are placed into the public domain and can be considered by the Commissioning Team. The structure of these commissioning notes is flexible; there is no specific template required. A brief informal document (e.g., 2-3 pages) could be sufficient. More information is welcome. There is no length restriction for the notes. Supplemental digital resources are welcome.
Potential topics to be addressed in the commissioning notes:
- What observations would be most helpful for science validation studies during the early integration and test periods with ComCam and the full LSSTCam? Note that during these periods, the configuration of the system might not be fully optimal for science performance. What studies would be possible with, for example, an hour or a few hours of on-sky observations?
- Are there specific target fields and/or objects that would be most valuable for science validation studies? It is most helpful to have a prioritized list of targets that span a range of RA coordinates.
- What external reference datasets are most valuable for science validation studies? Are specific observations needed to fully utilize these external reference datasets?
- The Project has been planning to conduct one or more multi-night science verification surveys. There is a trade-space of depth, area coverage, and band coverage for a given amount of observing time. What factors should be taken into consideration when designing these science verification surveys?
- What observing cadences are needed to support science validation studies?
- What dither patterns should be tested?
- Are there other specific observations that should be considered not in the categories above?
Any materials posted by 4 December 2020 could be taken into consideration as part of the re-plan exercise currently being undertaken by the Project. These commissioning notes can be updated at any time. Anyone may submit a commissioning note. Commissions liaisons designated by their respective Science Collaborations are encouraged to curate the guidance from their Science Collaborations.
Based on the commissioning notes received in Phase 1, the Project will iterate with the community to refine proposals. The details of this second phase will be determined closer to the time of first light.
- Parallel session on community input to the commissioning observing strategy at the PCW 2020, including many contributed presentations
- Commissioning Plan (LSE-79; note that current version does not reflect the de-scope options exercised over the past year in LCR-1966 and LCR-2045; namely the reduction of sustained observing periods with both ComCam and LSSTCam)
- LSST System Requirements (LSR: LSE-29)
- Observatory System Specifications (OSS: LSE-30)
Many thanks in advance for sharing your expertise and ideas.
Keith Bechtol and Chuck Claver