CLASS 40 GHz 2016 - 2022 Observations (DR1)

Polarization Maps

Coordinate System:
Projection Type:
HEALPix, ring, Nside=128
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The CLASS 2016 - 2022 40 GHz survey covers roughly 75% of the sky, with declination coverage -76° ≤ δ ≤ +30°. Polarization maps are provided in three FITS files: one file contains the V, Q and U maps constructed using the full 2016 - 2022 survey period, and the other two files contain V, Q and U maps for two data splits (base splits m1 and m2). Each base split consists of approximately half of the full mapped data and includes each distinct observational condition in nearly the same proportion as in the full survey map. Hits maps, as described in Li et al. (2023), are provided in fields QQ, QU, QV, UU, UV and VV. Hits are proportional to the inverse-variance assuming constant white noise in the raw data around the VPM modulation frequencies.

The CLASS mapmaking pipeline applied filtering to the 40 GHz time-domain data to remove systematic signals encountered in the data. The data release includes a mapping transfer function in the form of a matrix with VV, EE and BB blocks applicable in the harmonic domain. Noise simulations are also provided for the purpose of evaluating the significance of results. These products are documented in more detail on separate pages.

Additional Information:

CLASS Data Pipeline and Maps for 40 GHz Observations through 2022, Li et al. (2023)

CLASS Angular Power Spectra and Map-Component Analysis for 40 GHz Observations through 2022, Eimer et al. (2023)

A service of the HEASARC and of the Astrophysics Science Division at NASA/GSFC
Goddard Space Flight Center, National Aeronautics and Space Administration
HEASARC Director: Dr. Andrew F. Ptak
LAMBDA Director: Dr. Thomas M. Essinger-Hileman
NASA Official: Dr. Thomas M. Essinger-Hileman
Web Curator: Mr. Michael R. Greason