Sky Components

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These are effectively a library of component skies which can be added up to produce models of what the total CMB+foreground sky might look like under different assumptions.

Scalar CMB: Borrill

  • consistent with Planck 2015 and low τ parameters
  • alm's for 1000 realizations of LCDM are on NERSC in directory: /project/projectdirs/cmb/data/generic/cmb/ffp10/mc/scalar with the input spectra in /project/projectdirs/cmb/data/generic/cmb/ffp10/cls
  • Both lensed and unlensed alm's are provided for each realization with names like ffp10_lensed_scl_cmb_000_alm_mc_0000.fits and ffp10_unlensed_scl_cmb_000_tebplm_mc_0000.fits
  • The lensing map appears to be in the fourth binary table of ffp10_unlensed_scl_cmb_000_tebplm_mc_0000.fits

Tensor CMB: Borrill

  • alm's for 1000 realizations of IGW tensors are on NERSC in directory: /project/projectdirs/cmb/data/generic/cmb/ffp10/mc/tensor with the input spectra in /project/projectdirs/cmb/data/generic/cmb/ffp10/cls
  • these have a tensor/scalar ratio of 0.01, so for other values need to rescale them by 10*sqrt(r)

Gaussian dust

  • Amplitude (in BB spectrum) is 4.25 μK2 at ν = 353 GHz, ℓ = 80. This is the value that was used for Science Book forecasts and is listed in Victor's 2016-05-31 posting (Section 2). It also corresponds to the best fit dust amplitude from the BK14 result.
  • Dust amplitude in EE is 2x larger than BB. Dust amplitude in TT is 10x larger than EE (20x larger than BB). There is no TE, TB, or EB correlation.
  • Dust scaling in frequency follows a greybody spectrum with βdust = 1.6 and Tdust = 19.6 K. This choice of parameters comes from PIPXXX.
  • Dust D scaling follows a power law in ell with exponent αdust = -0.4. This parameter also comes from PIPXXX.
  • These cls, alms and maps are posted on NERSC under directory: /project/projectdirs/cmbs4/input_sky_comps/gdust

Gaussian synchrotron

  • Amplitude (in BB spectrum) is 3.8 μK2 at ν = 23 GHz, ℓ = 80. This is the value that was used for Science Book forecasts and is listed in Victor's 2016-05-31 posting (Section 2). It also corresponds to the 95% upper limit from the BK14 result.
  • Sync amplitude in EE is 2x larger than BB. Sync amplitude in TT is 10x larger than EE (20x larger than BB). There is no TE, TB, or EB correlation.
  • Sync scaling in frequency follows a power-law spectrum with βsync = -3.1.
  • Sync D scaling follows a power law in ell with exponent αsync = -0.6.
  • These cls, alms and maps are posted on NERSC under directory: /project/projectdirs/cmbs4/input_sky_comps/gsync

PySM

  • Maps of the PySM model have been provided at /project/projectdirs/cmb/data/generic/galactic/pysm_X.0
  • There is a single realization at each frequency integrated over top hat bandwidths.
  • Three variants are currently provided dubbed a1d1f1s1, a2d4f1s3 and a2d7f1s3 - see the paper linked above and GitHub for some description.