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Foregrounds and simulations

Post talks here:

  • r -- Lloyd Knox slides
  • TT/TE/EE -- Erminia Calabrese slides
  • Lensing -- Blake Sherwin slides
  • Clusters -- Colin Hill slides

Notes from session

Take notes here.

r: Lloyd Knox

  • From Science Book, expect two distinct surveys for r: one at low resolution with many frequencies (for tensors), one with high resolution but fewer frequencies (for delensing)
  • Defined a staged series of data challenges. Simulated maps exist at NERSC, analysis of first data challenge is underway. Start simple, update survey and signals in later rounds.
  • Science Book used Fisher forecast to allocate sensitivity between eight frequency bands for low-res survey plus high-res survey.
  • Important question: Do we need additional frequencies below 30 GHz?
  • Survey definitions:
    • X=1: Science Book case with fsky=3% (check codes to confirm that we can reproduce Science Book results)
    • X=2: Updated set of bandpasses, multiple values of fsky.
    • X=3: Include both low-res and high-res surveys
  • Signal definitions:
    • Y=0: Lensed and partially-delensed CMB, Gaussian dust and synchrotron, no extragalactic foregrounds
    • Y=1: PySM 'standard' model = Galactic foregrounds (non-Gaussian, spatially varying indices for sync/dust), no extragalactic foregrounds
    • Y=2: PySM 'alternate' model
    • Y>2: Ben Thorne and Brandon Hensley working to add Hensley / Drain dust model, add extragalactic foregrounds consistent with CMB lensing (Alvarez/Battaglia/Bond)

TT/TE/EE: Erminia Calabrese

Lensing: Blake Sherwin

Clusters: Colin Hill

Action items/Next steps

Summarize action items here