This page provides the new full-sky Galactic dust reddening E(B−V) map and associated data products described in Chiang 2023 (arXiv:2306.03926).
This dust map improves upon the widely used Schlegel, Finkbeiner, & Davis (1998, SFD) map by removing a tomographically reconstructed cosmic infrared background (CIB) component that contaminates the original SFD. This new dust map enables more accurate Galactic extinction corrections for extragalactic photometry.
The CSFD dust map in full-sky Galactic mollweide projection.
Comparison with SFD:
Zoomed-in views in a 20 deg field (at l = −50°, b = −80°) for the original SFD, the new CSFD, and the reconstructed CIB. The CSFD map is made to be free of extragalactic contamination: CSFD = SFD − CIB. Stacked images of the Galactic reddening estimates in SFD and CSFD around 4 samples of extragalactic objects. CIB contamination (dominated by 2-halo clustering) is seen in SFD, and is mostly gone in CSFD. The lower last panel reveals a true selection effect against high-dust-column sky for faint cosmology targets, which can now be removed by re-thresholding using CSFD.
Reconstruction of the CIB map:
The reconstructed CIB map is made by finding the optimal combination of 180 template maps to reproduce the redshift and angular tomographic cross-correlation statistics of the CIB in SFD. These templates are constructed from the density fields of over 600 million galaxies in WISE, thus carrying the true orientations (or Fourier phases) of the cosmic filaments, voids, and clusters in our Universe. An additional template is used to mask bright far-IR sources. This CIB map is subtracted from SFD to get the cleaned CSFD map.
Data Products:
The following data products can be found in this link:
CSFD, the CIB-free, corrected SFD Galactic dust reddening E(B−V) map.
The original SFD recast in the HEALPix format (NSIDE=2048).
Reconstructed CIB intensity map in MJy sr−1.
Error map of the reconstructed CIB field.
Bitmask indicating the LSS correction footprint and the most reliable cosmology area.
Contact:
If you have questions regarding these products, please contact Yi-Kuan Chiang (ykchiangasiaa.sinica.edu.tw).
asiaa.sinica.edu.tw).