Foreground: Polarized Synchrotron Spectral Index
HEALPix, nested, res 4 (Nside=16)
Original Data Source:
Weiland et al. (2022)
Weiland et al. (2022) performed a combined analysis of observational data at 1.4, 2.3, 23, and 33 GHz to quantify the spatial variation of the polarized synchrotron spectral index on 3.5° scales. Data quality masking leaves 44% sky coverage (73% for Galactic latitudes |b| > 45°).
The FITS binary table formatted file contains three fields:
(1) the derived map of the polarized synchrotron spectral index, (2) its uncertainty, and (3) a numerically coded mask indicating which frequencies were used to compute the spectral index for each pixel. The numerical coding values are documented in the FITS header.
More details can be found in: