We present a catalog of galaxy clusters detected in a new ROSAT PSPC survey. The survey is optimized to sample, at high redshifts, the mass range corresponding to T>5keV clusters at z=0. Technically, our survey is the extension of the 160 square degree survey (160d, Cat. J/ApJ/502/558). We use the same detection algorithm, thus preserving high quality of the resulting sample; the main difference is a significant increase in sky coverage. The new survey covers 397deg^2^ and is based on 1610 high Galactic latitude ROSAT PSPC pointings, virtually all pointed ROSAT data suitable for the detection of distant clusters. The search volume for X-ray luminous clusters within z<1 exceeds that of the entire local universe (z<0.1). We detected 287 extended X-ray sources with fluxes f>1.4x10^-13^ergs/s/cm^2^ in the 0.5-2keV energy band, of which 266 (93%) are optically confirmed as galaxy clusters, groups or individual elliptical galaxies.
Detached eclipsing binary star systems are our primary source of measured physical properties of normal stars. I introduce DEBCat: a catalog of detached eclipsing binaries with mass and radius measurements to the 2% precision necessary to put useful constraints on theoretical models of stellar evolution. The catalog was begun in 2006, as an update of the compilation by Andersen (1991A&ARv...3...91A). It now contains over 195 systems (2017/10/10), and new results are added on appearance in the refereed literature.
The Deep Extragalactic Evolutionary Probe (DEEP) is a multi-year program which uses the twin 10m Keck Telescopes and the Hubble Space Telescope (HST) to conduct a truly large-scale survey of distant, faint, field galaxies. The broad scientific goals include: the formation and evolution of galaxies, the origin of large-scale structure, the nature of the dark matter, and the geometry of the Universe. This project is led by the Lick Observatory at University of California (UC) Santa Cruz, in collaboration with UC Berkeley, University of Hawaii (UH) Manoa, Johns Hopkins University, University of Chicago and California Institute of Technology. The photometric data were taken with the CFH12K camera on the 3.6-meter Canada-France-Hawai'i Telescope. Each DEEP2 field is covered by multiple CFHT/CFH12K pointings with each pointing numbered within its respective
We present a study of a 20cm selected sample in the Deep Spitzer Wide-area InfraRed Extragalactic Legacy Survey Very Large Array Field, reaching a 5{sigma} limiting flux density at the image center of S_1.4GHz_~13.5uJy. In a 0.6x0.6deg^2^ field, we are able to assign an optical/IR counterpart to 97% of the radio sources. Up to 11 passbands from the NUV to 4.5um are then used to sample the spectral energy distribution (SED) of these counterparts in order to investigate the nature of the host galaxies. By means of an SED template library and stellar population synthesis models, we estimate photometric redshifts, stellar masses, and stellar population properties, dividing the sample into three sub-classes of quiescent, intermediate, and star-forming galaxies. We focus on the radio sample in the redshift range 0.3<z<1.3 where we estimate to have a redshift completeness higher than 90% and study the properties and redshift evolution of these sub-populations.
This catalogue is the latest incremental release of the DENIS project. It consists of a set of 355,220,325 point sources detected by the DENIS survey in 3662 strips (covering each 30 degrees in declination and 12 arcmin in right ascension). The data in this release cover approximately 16700 square degrees of the Southern sky. Multiple detections of single point sources have been merged in image overlaps within individual strips, but sources can have multiple detections in overlaping strips. DENIS is the only astronomical survey of the Southern sky made in two near-infrared bands (J at 1.25{mu}m, and K_s_ at 2.15{mu}m) and one optical band (Gunn-i at 0.82{mu}m), with limiting magnitudes 16.5, 14 and 18.5, respectively. Saturation magnitudes are K_s_=6, J=7.5 and Gunn-i=9.8mag. It was conducted by a European consortium, using the 1m telescope at ESO, La Silla (Chile). The DENIS instrument is made up of a 3-channel camera built of commercially available detector arrays by the Observatoire de Paris and with major contributions from other European Institutes, notably: the IAS in Frascati, the Observatoire de Grenoble, the University of Innsbruck, the Observatoire de Lyon, and the IAC in Tenerife. The survey is carried out by observing strips of 30{deg} in declination and 12arcminutes in Right Ascension with an overlap of 2 arcminutes between consecutive strips. The survey started at the end of 1995 and has been completed up to 97% in 2001. The data have been reduced at the Institut d'Astrophysique de Paris and Observatoire de Paris. The position of a general extracted point source is provided with an accuracy better than 1arcsec and its magnitude to better than 0.1 mag. The Centre de Donnees Astronomiques de Strasbourg (CDS) is releasing the final databases and provides access of the processed and calibrated data to the worldwide community. The principal investigator of the DENIS project is N. Epchtein (Observatoire de la Cote d'Azur); the Co-PI in charge of data processing is G. Simon (observatoire de Paris); J. Borsenberger and B. de Batz, with the help of F. Tanguy, S. Begon and P. Texier, processed the data and implemented the working data base at PDAC; S. Derriere is in charge of the data release at CDS. Scientists and engineers from seven European countries and from Brazil are involved in the data qualification and analysis.
This paper announces the release at CDS of a substantial set of point sources detected by the DENIS project. DENIS is the first astronomical survey of the Southern sky in two near-infrared bands (J at 1.25{mu}m, and K_s_ at 2.15{mu}m) and one optical band (Gunn-i at 0.82{mu}m), conducted by a European consortium, using the 1m telescope at ESO, La Silla (Chile). The first data release, described here, consists of a preliminary set of about 17 million extracted point sources, corresponding to 102 strips (2% of the Southern sky), and resulting from observations performed in 1996.
This catalogue is an intermediate release of the DENIS project. It consists of a set of 195204157 point sources detected by the DENIS survey in 2239 strips (covering each 30 degrees in declination and 12 arcmin in right ascension). The data in this release cover approximately 11000 square degrees of the Southern sky. Multiple detections of single point sources have been merged in image overlaps within individual strips, but sources can have multiple detections in overlapping strips. The complete set of data collected by DENIS in the period 1996-2001 will be released towards the end of 2003. DENIS is the only astronomical survey of the Southern sky made in two near-infrared bands (J at 1.25{mu}m, and K_s_ at 2.15{mu}m) and one optical band (Gunn-i at 0.82{mu}m), with limiting magnitudes 14.0, 16.5 and 18.5, respectively. It was conducted by a European consortium, using the 1m telescope at ESO, La Silla (Chile). The DENIS instrument is made up of a 3-channel camera built of commercially available detector arrays by the Observatoire de Paris and with major contributions from other European Institutes, notably: the IAS in Frascati, the Observatoire de Grenoble, the University of Innsbruck, the Observatoire de Lyon, and the IAC in Tenerife. The survey is carried out by observing strips of 30{deg} in declination and 12arcminutes in Right Ascension with an overlap of 2arcminutes between consecutive strips. The survey started at the end of 1995 and has been completed up to 97% in 2001. The data have been reduced at the Institut d'Astrophysique de Paris and Observatoire de Paris. The position of a general extracted point source is provided with an accuracy better than 1arcsec and its magnitude to better than 0.1mag. The Centre de Donnees Astronomiques de Strasbourg (CDS) is releasing the final databases and provides access of the processed and calibrated data to the worldwide community. The principal investigator of the DENIS project is N. Epchtein (Observatoire de la Cote d'Azur); the Co-PI in charge of data processing is G. Simon (observatoire de Paris); J. Borsenberger and B. de Batz, with the help of F. Tanguy, S. Begon and P. Texier, processed the data and implemented the working data base at PDAC; S. Derriere is in charge of the data release at CDS. Scientists and engineers from seven European countries and from Brazil are involved in the data qualification and analysis.
The 2dF Galaxy Redshift Survey (2dFGRS) is a major spectroscopic survey taking full advantage of the unique capabilities of the 2dF facility built by the Anglo-Australian Observatory. The 2dFGRS is integrated with the 2dF QSO survey (2QZ, Cat. VII/241). The 2dFGRS obtained spectra for 245591 objects, mainly galaxies, brighter than a nominal extinction-corrected magnitude limit of b_J_=19.45. Reliable (quality>=3) redshifts were obtained for 221414 galaxies. The galaxies cover an area of approximately 1500 square degrees selected from the extended APM Galaxy Survey in three regions: a North Galactic Pole (NGP) strip, a South Galactic Pole (SGP) strip, and random fields scattered around the SGP strip. Redshifts are measured from spectra covering 3600-8000 Angstroms at a two-pixel resolution of 9.0 Angstrom and a median S/N of 13 per pixel. All redshift identifications are visually checked and assigned a quality parameter Q in the range 1-5; Q>=3 redshifts are 98.4% reliable and have an rms uncertainty of 85 km/s. The overall redshift completeness for Q>=3 redshifts is 91.8% but this varies with magnitude from 99% for the brightest galaxies to 90% for objects at the survey limit. The 2dFGRS data base is available on the World Wide Web at http://www.mso.anu.edu.au/2dFGRS/.
The 2dF Galaxy Redshift Survey (2dFGRS) is designed to measure redshifts for approximately 250000 galaxies. The 2dFGRS uses the 2dF multifibre spectrograph on the Anglo-Australian Telescope, which is capable of observing 400 objects simultaneously over a 2 degree diameter field. The source catalogue for the survey is a revised and extended version of the APM galaxy catalogue, and the targets are galaxies with extinction-corrected magnitudes brighter than bJ=19.45. The main survey regions are two declination strips, one in the southern Galactic hemisphere spanning 80x15degrees around the South Galactic Pole, and the other in the Northern Galactic hemisphere spanning 75x10degrees along the celestial equator; in addition, there are 99 fields spread over the southern Galactic cap. The survey covers 2000 square degrees and has a median depth of z=0.11. Adaptive tiling is used to give a highly uniform sampling rate of 93% over the whole survey region. The 100k release contains the 102426 objects observed up to 31 January 2001. Redshifts are measured from spectra covering 3600-8000 Angstroms at a two-pixel resolution of 9.0 Angstrom and a median S/N of 13 per pixel. All redshift identifications are visually checked and assigned a quality parameter Q in the range 1-5; Q>=3 redshifts are 98.4% reliable and have an rms uncertainty of 85 km/s. The overall redshift completeness for Q>=3 redshifts is 91.8% but this varies with magnitude from 99% for the brightest galaxies to 90% for objects at the survey limit. The 2dFGRS data base is available on the World Wide Web at http://www.mso.anu.edu.au/2dFGRS. This catalog was extracted from the 2dF Galaxy Redshift Survey 100k release CD-ROMs using the included mSQL database. This catalog comprises the basic spectroscopic information from the best spectrum of each object, that is contained in the extnum=0 rows of the mSQL database.
The final catalogue of the 2dF QSO Redshift Survey (2QZ) is based on Anglo-Australian Telescope 2dF spectroscopic observations of 44576 colour-selected (ub_J_r) objects with 18.25<b_J_< 20.85 selected from automated plate measurement scans of UK Schmidt Telescope (UKST) photographic plates. The 2QZ comprises 23338 quasi-stellar objects (QSOs), 12292 galactic stars (including 2071 white dwarfs) and 4558 compact narrow emission-line galaxies. We obtained a reliable spectroscopic identification for 86 per cent of objects observed with 2dF. We also report on the 6dF QSO Redshift Survey (6QZ), based on UKST 6dF observations of 1564 brighter (16<b_J_<18.25) sources selected from the same photographic input catalogue. In total, we identified 322 QSOs spectroscopically in the 6QZ. The completed 2QZ is, by more than a factor of 50, the largest homogeneous QSO catalogue ever constructed at these faint limits (b_J_<20.85) and high QSO surface densities (35 QSOs/deg^2^). As such, it represents an important resource in the study of the Universe at moderate-to-high redshifts.