SLAC-2017:Foregrounds

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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)

Action items/Next steps

Summarize action items here