UCSD-2019: Analysis/Pipeline Working Group: Maps to C ell

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Charge

Note that "Maps to Cl" is actually shorthand for "Maps to Cl to Parameters" or "Maps to Parameters from (non-low-ell-BB) Power Spectra." This is important for understanding the charge and defining the responsibilities of this group.

The charge from the meeting SOC is twofold (see https://docs.google.com/document/d/1KtRif7_BPi3gACMkIA7__AWK63iUJiljN6UlKI41MS0/edit for the exact charge). One part is a set of general instructions for all analysis working groups:

  • Identify key decisions that must be made (and justified) prior to CD-1,
  • Make progress on (or actually make) those decisions,
  • Lay out a timeline and process for making each decision, consistent with the post-decision work and internal reviews that will be needed to complete preparations for CD-1,
  • Ensure that those timelines and processes are understood and supported by the collaboration, and that we (together) believe we can follow them.

The other part is a set of specific questions to support other working groups / WBSs as we move to the next level of design. Our questions are:

  • How are we calibrating beams to meet high-ell science requirements? Can we use high S/N point sources alone?
  • How does the galaxy impact Neff inference?
  • Does this drive frequency coverage?
  • Is there a path to realistically achieve both the necessary cadence for transients and the necessary sky coverage for light relics goals?
  • What are the necessary analysis tools to answer these questions?

Agenda

Reminder: What are the science targets, and what was previously identified as important decisions / questions?

1. Light relics summary (Ben Wallisch, on behalf of Dan Green and Joel Meyers and others) slides

2. Dark matter science summary (Vera Gluscevic or Cora Dvorkin) slides

3. Isocurvature summary? (Dan Grin?)

General charge:

1. Identify key decisions that must be made (and justified) prior to CD-1

Some possible questions:

  • What level of sims to maps to Cell to parameters pipeline do we need for CD-1? Should a tool be developed to be used by the whole collaboration?
  • Should Maps to Cell and low-ell BB groups have a common set of simulations and analysis tools to be addressing “non-idealities” by CD-1?
  • What instrumental effects are important (eg time constants, ell-dependent gains, etc) and what limits need to be put on this for the science goals.
    • But also, what instrumental systematics can we put requirements on that will actually influence near-term design decisions?
    • Get a list of effects the low-ell BB group are limiting, to be able to make a statement about Neff needs for same issues?
  • Should we be setting up data challenges (e.g., make a CMB sky with beam properties varying across the field and have people analyze it and get unbiased Neff)?

2. Make progress on (or actually make) those decisions

Presumably this is done collectively by all session attendees.

3. Lay out a timeline and process for making each decision, consistent with the post-decision work and internal reviews that will be needed to complete preparations for CD-1

I imagine this will not be done in real time.

4. Ensure that those timelines and processes are understood and supported by the collaboration, and that we (together) believe we can follow them.

We can talk in the session about the best ways to ensure this.

Individual charge questions:

0. First an overview of N_eff forecasting from the Dark Universe session. (Ben Wallisch, on behalf of Dan Green and Joel Meyers and others) slides

  • Most of the individual charge questions deal with N_eff goals and requirements, so it's useful to remind ourselves what matters for N_eff and why we are pushing on the particular things we're pushing on.

Questions regarding systematics:

1. How are we calibrating beams to meet high-ell science requirements? Can we use high S/N point sources alone?

  • TC (I did an early study on this and can resurrect it for discussion) slides
  • What about T -> P leakage for Neff? (incl higher-order terms)

Questions regarding how much sky we could possibly observe without hitting some systematic or noise floor? (what is limiting fsky?)

2. How does the galaxy impact Neff inference and does this drive frequency coverage? (Colin Hill) slides

  • also think about ground pickup?

3. Is there a path to realistically achieve both the necessary cadence for transients and the necessary sky coverage for light relics goals? (Reijo Keskitalo) slides

4. What are the necessary analysis tools to answer these questions? (all, discussion)

Remote attendance

Zoom link


Notes

Early notes on planning/agenda are here: https://docs.google.com/document/d/1uxn1AedOzWAObeG59aS7WPfctV_GC6kDbDw0KgdR_Ow/edit#