CDT instrument baseline

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CMB INSTRUMENT BASELINE


--- Two sky surveys ------------

  • Small patch of the sky (<10% of the sky) + deep high-resolution observations of the same patch of the sky (for primordial gravitational waves and delensing, respectively);
  • Surve large patch of the sky (>> 10%), for light relic search.


PRIMORDIAL GRAVITATIONAL WAVES (4yrs surtvey) 1.jpg

LIGHT RELIC (7yrs survey) 2.jpg



Essential:

  • Fsky=0.4
  • Spatial resolution: 1’ at 150GHz;
  • Depth: 1 microK-arcmin at 150GHz;
  • Frequency coverage up to 270GHz;
  • Four/seven years of observations.


--- Telescopes ----------------

  • 0.5m aperture cameras, could be refracting (BICEP/Keck) or reflecting (ABS);
  • for 1.5’ at 150GHz -> at least 6m aperture telescope (6m Crossed-Dragone for CCAT), mature camera is refracting (AdvACT, POLARBEAR2, SPT-3G).


--- Detectors and Readout ----------------

Potentially viable:

  • feedhorns, lenslets, planar antenna arrays;
  • TDM, DfMUX, uMUX.

--- Cryogenics ----------------

  • 0.1K dilution refrigerator assumed;
  • measurements from Stage-III experiments will inform if the polarization modulator will be used.


--- Project risks ---------------- 3.jpg

TIMELINE

  • CDO (2019): start of the project
  • CD3 (2022): construction
  • CD4 (2016): start of operations
  • 4 years survey GW and inflation
  • 7 years survey