Redshifts are crucial for studying distant galaxies. They provide an estimate of distance, allowing one to relate observed to intrinsic properties and to cut through the projection on the sky to map the cosmic web and large-scale structure. Wide-field low-redshift surveys such as the SDSS have given us a detailed understanding of the multivariate properties of galaxies, including joint distributions of luminosity, color, morphology, and environment. The question now is how these galaxy properties evolve with time. Deep imaging surveys have covered as much volume at z=1 as the SDSS has at z=0.1, and much of this imaging is panchromatic, with UV and mid-IR data providing critical information about star-formation and stellar mass. For example, the Spitzer SWIRE and GTO surveys and GALEX Deep Imaging Survey have imaged ~60 square degrees to depths appropriate for z=1 galaxies. However, these imaging surveys lack redshifts.
PRIMUS is the largest faint galaxy spectroscopic redshift survey taken to date. It is a spectroscopic survey to z=1 with ~120,000 robust galaxy redshifts covering >9 sq. deg. of the sky, focusing on regions with deep Spitzer, optical, GALEX and X-ray data. Using a custom-built low-resolution prism on the IMACS instrument on the 6.5m Magellan/Baade telescope, we are able to obtain redshifts of faint galaxies ~10x faster than comparable spectroscopic redshift surveys with a precision of dz/(1+z)<0.005. This technique is faster than photometric redshift surveys and provides more precise redshifts.
PRIMUS is done taking data. We have released our redshift catalog and are writing science papers (arXiv Publications). Funding for PRIMUS is provided by NSF (AST-0607701, AST-0908246, AST-0908442, AST-0908354) and NASA (Spitzer-1356708, 08-ADP08-0019, NNX09AC95G).
Any questions regarding PRIMUS or DR1 should be directed to Alexander Mendez (firstname.lastname@example.org).
For any publication making use of PRIMUS data, the following acknowledgment should be included:
Funding for PRIMUS is provided by NSF (AST-0607701, AST-0908246, AST-0908442, AST-0908354) and NASA (Spitzer-1356708, 08-ADP08-0019, NNX09AC95G).
The two PRIMUS survey papers are given below.