PAU

Characterizing galaxies

The PAU Survey (PAUS) will provide completed fluxed limited accurate redshift and spectral energy distribution information for millions of galaxies (and stars) to a depth and area never explored before. This is done without the need of target selection which provides a valuable tool to understand sample selection and completeness.

Surveying spectral energy for millions of galaxies

The PAU Survey is an international collaboration between Spain, Holland, Switzerland, Germany, UK to collect a fluxed limited accurate redshift and spectral energy distribution information for millions of galaxies (and stars) to a depth and area never explored before. This is done without the need of target selection which provides a valuable tool to understand sample selection and completeness. To do this, a spanish group had built PAUcam, a large imager (1 degree square FoV, with18 CCD of 4094x2048 pixels each) capable of doing imaging with 40 narrow-band filters (~130A wide in steps of 100A) and 6 wide-band filtres (u,g,r,i,z,Y), which results in high resolution spectra energy distributions for all galaxies in a given field of view. A number of large surveys (e.g. KiDS, DES, SDSS, LSST, DESI) seeks to map the 3D structure of the Universe to understand the nature of dark matter and dark energy. Surveying large contiguous areas while simultaneously achieving a high number density of galaxies with sub-percent redshift accuracy is possible thanks to PAUCam. This exquisite wavelength sampling results in photometric redshifts with a precision that approaches that of spectroscopic measurements, while being able to cover large areas of sky.

ICE's participation

PAUCam has been designed and built entirely by a Consortium of Spanish Institutions (in alphabetical order: CIEMAT, Institute of Space Sciences (ICE-CSIC), IFAE, IFT/UAM, and PIC). The project was funded by the Consolider Ingenio 2010 programme of the Spanish Government. The PAUcam construction and integration was done in Barcelona UAB Campus at IFAE labs with the help of CIEMAT and Institute of Space Sciences' engineers and support from their own lab facilities. This was a join effort and the Institute of Space Sciences is leading the project (F.Castander is the PAUcam Project Scientist). Other main technical contributions from IEEC-CSIC were the procurement and characterization of CCD and filters, as well as other parts, built and operate the optical, cryogenic and electronic test bench, design and build camera guiding and alignment system, design and implement camera optical system and characterization. The Institute of Space Sciences is also leading the PAU Survey Collaboration (E.Gaztanaga is the Survey Director) and the data reduction, community pipeline, automated analysis pipelines and the data distribution in collaboration with PIC (Santi Serrano is the PAUdm Project Manager). Institute of Space Sciences is also leading the scientific exploitation of the PAUS data, including simulations, photometric redshift and clustering forecast and analysis.