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Maps to Power Spectra Breakout Report

Cynthia Trendafilova (she/her, they/them)�On behalf of the Working Group

CMB-S4 Summer Collaboration Meeting, August 2022

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  • Science topics for the Second Edition of the CMB-S4 Science Book

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  • DRAFT tool�
  • Science task list�
  • Current projects�
  • Power spectrum pipelines�
  • Instrument model and survey needs

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Summary

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  • Broad science case, not only key science drivers�
  • N_eff + Y_p forecasts:
    • Snowmass White Paper - “The Physics of Light Relics”�https://arxiv.org/abs/2203.07943
    • Snowmass White Paper - “Synergy between cosmological and laboratory searches in neutrino physics: a white paper”�https://arxiv.org/abs/2203.07377�
  • Nonthermal neutrinos�
  • Neutrino science:�m_nu, N_eff, L_nu, self-interactions, fraction of ~eV sterile neutrinos that have thermalized��

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Second Edition of Science Book

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  • Dark matter science:
    • Snowmass White Paper - “Dark Matter Physics from the CMB-S4 Experiment”�https://arxiv.org/abs/2203.07064
    • Snowmass White Paper - “The Physics of Light Relics”�https://arxiv.org/abs/2203.07943

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Second Edition of Science Book

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  • “Tensions” - early dark energy, self-interacting neutrinos, primordial magnetic fields�
  • Other high-ell BB science:�Non-inflationary gravitational waves, birefringence, vector modes�
  • Other new physics with secondaries�
  • Model independent forecasts�
  • …Other ideas?

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Second Edition of Science Book

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DRAFT Tool

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Science Task List

  • Continue to give feedback on this list

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Current Projects

  • Beam systematics - instrumentation checks (e.g. beam ellipticity)
  • Official forecasts for N_eff - project comment period until August 26th
  • Foreground systematics - project comment period until August 26th�

Power Spectrum Pipeline

  • People with pipeline experience are encouraged to get involved - join our mailing list & attend our telecons

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Reminders

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  • Used in current forecasts:
    • Noise model from PBDR
    • Footprint from hit maps
    • Extragalactic foreground model from SPT
    • Galactic foreground spectrum from pySM�
  • Looking ahead:
    • Data Challenge 1 will provide [for CHLAT] a more realistic idea of noise for wide survey maps.

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Instrument Model and Survey Needs