desi-bgs / feasibgs

desi-bgs

feasiBGS

package for planning the DESI Bright Galaxy Survey

feasibgs's Issues

spectral simulation validation notebook

In order to validate the spectral simulation, we need to compare the redshift success rates predicted by them to redshift success rates from actual observations. I already have a pipeline for doing this but it's scattered across different scripts.

Construct a single jupyter notebook that can take the observing conditions of a DESI BGS exposure (exposure time, sky brightness, etc) and

• construct spectral simulations with realistic signal-to-noise
• run redrock on the spectral simulations and calculate redshift success rates

BGS SV fields

BGS SV fields were revised back in April in order to maximize overlap with the DR9 SV footprint. At the time, SV was scheduled to happen before DR9 would be processed for the full footprint. So, DR9 imaging would be run on these SV regions, specified in the link, first. Now that this is not an issue we may want to revisit the BGS SV fields.

Here's the BGS SV fields from April --- selected using this notebook

nominal BGS TS

Omar pointed out a number of issues with the nominal BGS target selection based on the latest DR9 imaging.

• There are significant differences between the nominal BGS cuts in the north and south. The cuts remove significantly more objects in the north than in the south.

  • Do we want different cuts for the north and the south?

• The large galaxy mask and quality cuts remove a significant fraction of objects are in GAMA. For example, >70% of objects removed by FRACIN QC are GAMA objects. Meanwhile, they only contribute ~25/deg^2.

  • For SV do we want to relax the quality cuts for all target classes?
  • Do we want to relax the cuts for the nominal TS?

Based on Omar's update in 10/23/2020 BGS telecon

december collaboration meeting

DR9 imaging

DR9 imaging will be released this week. Let's use this issue to keep track of the tests that need to be run and coordinate efforts.

november SV workshop

November workshop will be from Nov 23-25. Details for the workshop an be found here. Here's the outline of the agenda:

Monday, Nov 23, 2020

1. Discussion of SV target selection for MWS, BGS, LRG, ELG, and quasars
2. Decision trees for MWS, BGS, LRG, ELG, and quasars

Tuesday, Nov 24, 2020
3. Field selection, Fiber assignment, and Operations
4. Visual inspections

Wednesday, Nov 25, 2020
5. TS paper outlines
6. Data systems/WG communication

We need to make sure that we're prepared for agenda items:

• [1] updated SV target selection talk @qmxp55
• [2] updated decision tree talk with updated numbers from DR9 @changhoonhahn
• [3] create table of BGS SV fields with details on when they are observable @michaelJwilson @changhoonhahn
• [6] @michaelJwilson @changhoonhahn

reCMX BGS fields

BGS survey planning can significantly benefit from additional observation during reCMX.

• observing additional fields during bright time will help with calibrating the spectral simulations
• extra sky fibers will help fit the exposure time fraction calculator

Here was our proposal for reCMX:

• for a single BGS field
  • 1 - 4 exps during dark time
  • 2 consecutive exps during bright time with fsky × (tnom = 170s)
  • repeat on different bright night
• sky fibers during bright time: high moon illumination, high moon
  altitude, and low moon separation

SV 1% survey preparation

We need to start preparing for the analyses we can do with the SV 1% survey. We need to identify WG members for different projects and track the progress of each project through monthly updates. Here are some potential projects and a tentative list of members who are interested:

• HOD analysis: HOD fitting of clustering (Shadab, Joe)
• Emulator RSD: RSD analysis an emulator (Joe, Risa, Jeremy, Martin)
• Galaxy-group RSD: (Ellen, Shadab, John)
• Maximum likelihood luminosity function & stellar mass function: (Sam, Shaun)
• ...

visual inspection of spectra

We need to complete the second round of visual inspection for BGS. This is particularly important for BGS because the second tile (70500) was observed during bright time.

2 slides on 2021 priorities for December 2020 meeting

We will have a short discussion at the end of the meeting next on our priorities for the coming year. Can you send 1 or 2 slides of what you view as the BGS WG priorities or issues to resolve in that timeframe?

reCMX calibration/non-science exposures

We need to use calibration and non-science exposures during reCMX for validating: the sky model, the spectral simulations, or the survey simulations.

• Can we expect bright sky fibers from calibration/non-science exposures during reCMX?
• If so, do we have anyone who can process the data?