Mapping the Cosmic Web with the largest all-sky surveys
Abstract
Our view of the low-redshift Cosmic Web has been revolutionized by galaxy redshift surveys such as 6dFGS, SDSS and 2MRS. However, the trade-off between depth and angular coverage limits a systematic three-dimensional account of the entire sky beyond the Local Volume (z<0.05). In order to reliably map the Universe to cosmologically significant depths over the full celestial sphere, one must draw on multiwavelength datasets and state-of-the-art photometric redshift techniques. We have undertaken a dedicated program of cross-matching the largest photometric all-sky surveys -- 2MASS, WISE and SuperCOSMOS -- to obtain accurate redshift estimates of millions of galaxies. The first outcome of these efforts -- the 2MASS Photometric Redshift catalog (2MPZ, Bilicki et al. 2014a) -- has been publicly released and includes almost 1 million galaxies with a mean redshift of z=0.08. Here we summarize how this catalog was constructed and how using the WISE mid-infrared sample together with SuperCOSMOS optical data allows us to push to redshift shells of z~0.2--0.3 on unprecedented angular scales. Our catalogs, with ~20 million sources in total, provide access to cosmological volumes crucial for studies of local galaxy flows (clustering dipole, bulk flow) and cross-correlations with the cosmic microwave background such as the integrated Sachs-Wolfe effect or lensing studies.
Keywords
Cite
@article{arxiv.1408.0799,
title = {Mapping the Cosmic Web with the largest all-sky surveys},
author = {Maciej Bilicki and John A. Peacock and Thomas H. Jarrett and Michelle E. Cluver and Louise Steward},
journal= {arXiv preprint arXiv:1408.0799},
year = {2016}
}
Comments
Proceedings of IAU Symposium 308 "The Zeldovich Universe: Genesis and Growth of the Cosmic Web", 23-28 June 2014, Tallinn, Estonia