J-PAS: The Javalambre-Physics of the Accelerated Universe Astrophysical\n Survey

The Javalambre-Physics of the Accelerated Universe Astrophysical Survey\n(J-PAS) is a narrow band, very wide field Cosmological Survey to be carried out\nfrom the Javalambre Observatory in Spain with a purpose-built, dedicated 2.5m\ntelescope and a 4.7 sq.deg. camera with 1.2Gpix. Starting in late 2015, J-PAS\nwill observe 8500sq.deg. of Northern Sky and measure $0.003(1+z)$ photo-z for\n$9\\times10^7$ LRG and ELG galaxies plus several million QSOs, sampling an\neffective volume of $\\sim 14$ Gpc$^3$ up to $z=1.3$ and becoming the first\nradial BAO experiment to reach Stage IV. J-PAS will detect $7\\times 10^5$\ngalaxy clusters and groups, setting constrains on Dark Energy which rival those\nobtained from its BAO measurements. Thanks to the superb characteristics of the\nsite (seeing ~0.7 arcsec), J-PAS is expected to obtain a deep, sub-arcsec image\nof the Northern sky, which combined with its unique photo-z precision will\nproduce one of the most powerful cosmological lensing surveys before the\narrival of Euclid. J-PAS unprecedented spectral time domain information will\nenable a self-contained SN survey that, without the need for external\nspectroscopic follow-up, will detect, classify and measure $\\sigma_z\\sim 0.5\\%$\nredshifts for $\\sim 4000$ SNeIa and $\\sim 900$ core-collapse SNe. The key to\nthe J-PAS potential is its innovative approach: a contiguous system of 54\nfilters with $145\\AA$ width, placed $100\\AA$ apart over a multi-degree FoV is a\npowerful "redshift machine", with the survey speed of a 4000 multiplexing low\nresolution spectrograph, but many times cheaper and much faster to build. The\nJ-PAS camera is equivalent to a 4.7 sq.deg. "IFU" and it will produce a\ntime-resolved, 3D image of the Northern Sky with a very wide range of\nAstrophysical applications in Galaxy Evolution, the nearby Universe and the\nstudy of resolved stellar populations.\n