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Laureijs R.,European Space Agency | Racca G.,European Space Agency | Stagnaro L.,European Space Agency | Salvignol J.-C.,European Space Agency | And 29 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

In June 2012, Euclid, ESA's Cosmology mission was approved for implementation. Afterwards the industrial contracts were signed for the payload module and the spacecraft prime, and the mission requirements consolidated. We present the status of the mission in the light of the design solutions adopted by the contractors. The performances of the spacecraft in its operation, the telescope assembly, the scientific instruments as well as the data-processing have been carefully budgeted to meet the demanding scientific requirements. We give an overview of the system and where necessary the key items for the interfaces between the subsystems. © 2014 SPIE. Source


Laureijs R.,European Space Agency | Gondoin P.,European Space Agency | Duvet L.,European Space Agency | Saavedra Criado G.,European Space Agency | And 17 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2012

Euclid is a space-borne survey mission developed and operated by ESA. It is designed to understand the origin of the Universe's accelerating expansion. Euclid will use cosmological probes to investigate the nature of dark energy, dark matter and gravity by tracking their observational signatures on the geometry of the Universe and on the history of structure formation. The mission is optimised for the measurement of two independent cosmological probes: weak gravitational lensing and galaxy clustering. The payload consists of a 1.2 m Korsch telescope designed to provide a large field of view. The light is directed to two instruments provided by the Euclid Consortium: a visual imager (VIS) and a near-infrared spectrometer-photometer (NISP). Both instruments cover a large common field of view of 0.54 deg2, to be able to survey at least 15,000 deg2 for a nominal mission of 6 years. An overview of the mission will be presented: the scientific objectives, payload, satellite, and science operations. We report on the status of the Euclid mission with a foreseen launch in 2019. © 2012 SPIE. Source


Cuillandre J.-C.,Canada France Hawaii Telescope | Withington K.,Canada France Hawaii Telescope | Hudelot P.,CNRS Paris Institute of Astrophysics | Goranova Y.,CNRS Paris Institute of Astrophysics | And 11 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2012

The Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) is a high impact scientific program which will see its final official release open to the world in 2012. That release will seal the legacy aspect of the survey which has already produced a large collection of scientific articles with topics ranging from cosmology to the Solar system. The survey core science was focused on dark energy and dark matter: the full realization of the scientific potential of the data set gathered between 2003 and 2009 with the MegaCam wide-field imager mounted at the CFHT prime focus is almost complete with the Supernovae Legacy Survey (SNLS) team preparing its third and last release (SNLS5), and the CFHTLenS team planning the release based around the cosmic shear survey later this year. While the data processing center TERAPIX offered to the CFHTLS scientific community regular releases over the course of the survey in its data acquisition phase (T0001-T0006), the final release took three years to refine in order to produce a pristine data collection photometrically calibrated at better than the percent both internally and externally over the total survey surface of 155 square degrees in all five photometric bands (u*, g', r', i', z'). This final release, called T0007, benefits from the various advances in photometric calibration MegaCam has benefited through the joint effort between SNLS and CFHT to calibrate MegaCam at levels unexplored for an optical wide-field imager. T0007 stacks and catalogs produced by TERAPIX will be made available to the world at CADC while the CDS will offer a full integration of the release in its VO tools from VizieR to Aladin. The photometric redshifts have been produced to be released in phase with the survey. This proceeding is a general introduction to the survey and aims at presenting its final release in broad terms. © 2012 SPIE. Source


Ivison R.J.,Astronomy Technology Center | Ivison R.J.,University of Edinburgh | Swinbank A.M.,Durham University | Swinyard B.,Rutherford Appleton Laboratory | And 37 more authors.
Astronomy and Astrophysics | Year: 2010

We present a detailed analysis of the far-infrared (-IR) properties of the bright, lensed, z = 2.3, submillimetre-selected galaxy (SMG), SMM J2135-0102 (hereafter SMM J2135), using new observations with Herschel, SCUBA-2 and the Very Large Array (VLA). These data allow us to constrain the galaxy's spectral energy distribution (SED) and show that it has an intrinsic rest-frame 8-1000-μm luminosity, Lbol, of (2.3±0.2) × 10 12 L⊙ and a likely star-formation rate (SFR) of ∼400 M⊙ yr-1. The galaxy sits on the far-IR/radio correlation for far-IR-selected galaxies. At ≥70 μm, the SED can be described adequately by dust components with dust temperatures, Td ∼ 30 and 60 k. Using SPIRE's Fourier- transform spectrometer (FTS) we report a detection of the [C ii] 158 μm cooling line. If the [C ii], CO and far-IR continuum arise in photo-dissociation regions (PDRs), we derive a characteristic gas density, n ∼ 103 cm-3, and a far-ultraviolet (-UV) radiation field, G0, 103× stronger than the Milky Way. L[CII]/Lbol is significantly higher than in local ultra-luminous IR galaxies (ULIRGs) but similar to the values found in local star-forming galaxies and starburst nuclei. This is consistent with SMM J2135 being powered by starburst clumps distributed across ∼2 kpc, evidence that SMGs are not simply scaled-up ULIRGs. Our results show that SPIRE's FTS has the ability to measure the redshifts of distant, obscured galaxies via the blind detection of atomic cooling lines, but it will not be competitive with ground-based CO-line searches. It will, however, allow detailed study of the integrated properties of high-redshift galaxies, as well as the chemistry of their interstellar medium (ISM), once more suitably bright candidates have been found. © ESO 2010. Source


Pieri M.M.,Ohio State University | Pieri M.M.,University of Colorado at Boulder | Frank S.,Observatoire Astronomique de Marseille Provence | Weinberg D.H.,Ohio State University | And 3 more authors.
Astrophysical Journal Letters | Year: 2010

We present a new method for probing the physical conditions and metal enrichment of the intergalactic medium: the composite spectrum of Lyα forest absorbers. We apply this technique to a sample of 9480 Lyα absorbers with redshift 2 < z < 3.5 identified in the spectra of 13,279 high-redshift quasars from the Sloan Digital Sky Survey (SDSS) Fifth Data Release (DR5). Absorbers are selected as local minima in the spectra with 2.4 < τLyα < 4.0; at SDSS resolution (≈150 km s -1 FWHM), these absorbers are blends of systems that are individually weaker. In the stacked spectra, we detect seven Lyman series lines and metal lines of O VI, N V, C IV, C III, Si IV, C II, Al II, Si II, Fe II, Mg II, and O I. Many of these lines have peak optical depths of <0.02, but they are nonetheless detected at high statistical significance. Modeling the Lyman series measurements implies that our selected systems have total Hi column densities NHI ≈ 1015.4 cm-2. Assuming typical physical conditions ρ/ρ̄= 10, T = 104-104.5 K, and [Fe/H]= -2 yields reasonable agreement with the line strengths of high-ionization species, but it underpredicts the low-ionization species by two orders of magnitude or more. This discrepancy suggests that the low-ionization lines arise in dense, cool, metal-rich clumps, present in some absorption systems. © 2010 The American Astronomical Society. All rights reserved. Source

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