- ID:
- ivo://CDS.VizieR/J/A+A/570/A11
- Title:
- The Hawk-I UDS and GOODS Survey (HUGS)
- Short Name:
- J/A+A/570/A11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a new, ultra-deep, near-infrared imaging survey executed with the Hawk-I imager at the ESO VLT, of which we make all the data (images and catalog) public. This survey, named HUGS (Hawk-I UDS and GOODS Survey), provides deep, high-quality imaging in the K and Y bands over the portions of the UKIDSS UDS and GOODS-South fields covered by the CANDELS HST WFC3/IR survey. In this paper we describe the survey strategy, the observational campaign, the data reduction process, and the data quality. We show that, thanks to exquisite image quality and extremely long exposure times, HUGS delivers the deepest K-band images ever collected over areas of cosmological interest, and in general ideally complements the CANDELS data set in terms of image quality and depth. In the GOODS-S field, the K-band observations cover the whole CANDELS area with a complex geometry made of 6 different, partly overlapping pointings, in order to best match the deep and wide areas of CANDELS imaging. In the deepest region (which includes most of the Hubble Ultra Deep Field) exposure times exceed 80 hours of integration, yielding a 1-{sigma} magnitude limit per square arcsec of ~=28.0ABmag. The seeing is exceptional and homogeneous across the various pointings, confined to the range 0.38-0.43arcsec. In the UDS field the survey is about one magnitude shallower (to match the correspondingly shallower depth of the CANDELS images) but includes also Y-band band imaging (which, in the UDS, was not provided by the CANDELS WFC3/IR imaging). In the K-band, with an average exposure time of 13 hours, and seeing in the range 0.37-0.43arcsec, the 1-{sigma} limit per square arcsec in the UDS imaging is ~=27.3ABmag. In the Y-band, with an average exposure time ~=8h, and seeing in the range 0.45-0.5arcsec, the imaging yields a 1-{sigma} limit per square arcsec of ~=28.3ABmag. We show that the HUGS observations are well matched to the depth of the CANDELS WFC3/IR data, since the majority of even the faintest galaxies detected in the CANDELS H-band images are also detected in HUGS. Finally we present the K-band galaxy number counts produced by combining the HUGS data from the two fields. We show that the slope of the number counts depends sensitively on the assumed distribution of galaxy sizes, with potential impact on the estimated extra-galactic background light.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/891/129
- Title:
- The HeCS-omnibus catalog: SDSS & MMT sp. obs.
- Short Name:
- J/ApJ/891/129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore connections between brightest cluster galaxies (BCGs) and their host clusters. We first construct a HeCS-omnibus cluster sample including 227 galaxy clusters within 0.02<z<0.30; the total number of spectroscopic members from MMT/Hectospec and SDSS observations is 52325. Taking advantage of the large spectroscopic sample, we compute physical properties of the clusters including the dynamical mass and cluster velocity dispersion ({sigma}_cl_). We also measure the central stellar velocity dispersion of the BCGs ({sigma}_*,BCGs_) to examine the relation between BCG velocity dispersion and cluster velocity dispersion for the first time. The observed relation between BCG velocity dispersion and the cluster velocity dispersion is remarkably tight. Interestingly, the {sigma}_*,BCG_/{sigma}_cl_ ratio decreases as a function of {sigma}_cl_ unlike the prediction from the numerical simulation of Dolag+ (2010MNRAS.405.1544D). The trend in {sigma}_*,BCG_/{sigma}_cl_ suggests that BCG formation is more efficient in lower mass halos.
- ID:
- ivo://CDS.VizieR/J/ApJ/855/100
- Title:
- The HectoMAP cluster survey. II. X-ray clusters
- Short Name:
- J/ApJ/855/100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We apply a friends-of-friends algorithm to the HectoMAP redshift survey and cross-identify associated X-ray emission in the ROSAT All-Sky Survey data (RASS). The resulting flux-limited catalog of X-ray cluster surveys is complete to a limiting flux of ~3x10^-13^erg/s/cm^2^ and includes 15 clusters (7 newly discovered) with redshifts z<=0.4. HectoMAP is a dense survey (~1200 galaxies deg^-2^) that provides ~50 members (median) in each X-ray cluster. We provide redshifts for the 1036 cluster members. Subaru/Hyper Suprime-Cam imaging covers three of the X-ray systems and confirms that they are impressive clusters. The HectoMAP X-ray clusters have an LX-{sigma}cl scaling relation similar to that of known massive X-ray clusters. The HectoMAP X-ray cluster sample predicts ~12000+/-3000 detectable X-ray clusters in RASS to the limiting flux, comparable with previous estimates.
- ID:
- ivo://CDS.VizieR/J/ApJS/224/5
- Title:
- The Herschel Orion Protostar Survey (HOPS): SEDs
- Short Name:
- J/ApJS/224/5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present key results from the Herschel Orion Protostar Survey (HOPS): spectral energy distributions (SEDs) and model fits of 330 young stellar objects, predominantly protostars, in the Orion molecular clouds. This is the largest sample of protostars studied in a single, nearby star formation complex. With near-infrared photometry from 2MASS, mid- and far-infrared data from Spitzer and Herschel, and submillimeter photometry from APEX, our SEDs cover 1.2-870{mu}m and sample the peak of the protostellar envelope emission at ~100{mu}m. Using mid-IR spectral indices and bolometric temperatures, we classify our sample into 92 Class 0 protostars, 125 Class I protostars, 102 flat-spectrum sources, and 11 Class II pre-main-sequence stars. We implement a simple protostellar model (including a disk in an infalling envelope with outflow cavities) to generate a grid of 30400 model SEDs and use it to determine the best-fit model parameters for each protostar. We argue that far-IR data are essential for accurate constraints on protostellar envelope properties. We find that most protostars, and in particular the flat-spectrum sources, are well fit. The median envelope density and median inclination angle decrease from Class 0 to Class I to flat-spectrum protostars, despite the broad range in best-fit parameters in each of the three categories. We also discuss degeneracies in our model parameters. Our results confirm that the different protostellar classes generally correspond to an evolutionary sequence with a decreasing envelope infall rate, but the inclination angle also plays a role in the appearance, and thus interpretation, of the SEDs.
- ID:
- ivo://CDS.VizieR/J/AJ/156/186
- Title:
- The High Cadence Transit Survey (HiTS)
- Short Name:
- J/AJ/156/186
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The High Cadence Transient Survey (HiTS) aims to discover and study transient objects with characteristic timescales between hours and days, such as pulsating, eclipsing, and exploding stars. This survey represents a unique laboratory to explore large etendue observations from cadences of about 0.1 days and test new computational tools for the analysis of large data. This work follows a fully data science approach, from the raw data to the analysis and classification of variable sources. We compile a catalog of ~15 million object detections and a catalog of ~2.5 million light curves classified by variability. The typical depth of the survey is 24.2, 24.3, 24.1, and 23.8 in the u, g, r, and i bands, respectively. We classified all point-like nonmoving sources by first extracting features from their light curves and then applying a random forest classifier. For the classification, we used a training set constructed using a combination of cross-matched catalogs, visual inspection, transfer/active learning, and data augmentation. The classification model consists of several random forest classifiers organized in a hierarchical scheme. The classifier accuracy estimated on a test set is approximately 97%. In the unlabeled data, 3485 sources were classified as variables, of which 1321 were classified as periodic. Among the periodic classes, we discovered with high confidence one {delta} Scuti, 39 eclipsing binaries, 48 rotational variables, and 90 RR Lyrae, and for the nonperiodic classes, we discovered one cataclysmic variable, 630 QSOs, and one supernova candidate.
- ID:
- ivo://CDS.VizieR/J/ApJS/194/32
- Title:
- The HII Region Discovery Survey (HRDS). II.
- Short Name:
- J/ApJS/194/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Green Bank Telescope (GBT) HII Region Discovery Survey has doubled the number of known HII regions in the Galactic zone 343{deg}<=l<=67{deg} with |b|<=1{deg}. We detected 603 discrete hydrogen radio recombination line (RRL) components at 9GHz (3cm) from 448 targets. Our targets were selected based on spatially coincident mid-infrared and 20cm radio continuum emission. Such sources are almost invariably HII regions; we detected hydrogen RRL emission from 95% of our target sample. The sensitivity of the GBT and the power of its spectrometer together made this survey possible. Here, we provide a catalog of the measured properties of the RRL and continuum emission from the survey nebulae. The derived survey completeness limit, 180mJy at 9GHz, is sufficient to detect all HII regions ionized by single O-stars to a distance of 12kpc. We discovered 34 first quadrant negative-velocity HII regions, which lie at extreme distances from the Sun and appear to be part of the Outer Arm. We found RRL emission from 208 Spitzer GLIMPSE 8.0um "bubble" sources, 65 of which have been cataloged previously. It thus appears that nearly all GLIMPSE bubbles are HII regions and that ~50% of all Galactic HII regions have a bubble morphology at 8.0um.
1837. The HIZOA-S survey
- ID:
- ivo://CDS.VizieR/J/AJ/151/52
- Title:
- The HIZOA-S survey
- Short Name:
- J/AJ/151/52
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A blind HI survey of the extragalactic sky behind the southern Milky Way has been conducted with the multibeam receiver on the 64m Parkes radio telescope. The survey covers the Galactic longitude range 212{deg}<l<36{deg} and Galactic latitudes |b|<5{deg} to an rms sensitivity of 6mJy per beam per 27km/s channel and yields 883 galaxies to a recessional velocity of 12000km/s. The survey covers the sky within the HI Parkes All-Sky Survey (HIPASS) area to greater sensitivity, finding lower HI mass galaxies at all distances, and probing more completely the large-scale structures at and beyond the distance of the Great Attractor. Fifty-one percent of the HI detections have an optical/near-infrared (NIR) counterpart in the literature. A further 27% have new counterparts found in existing, or newly obtained, optical/NIR images. The counterpart rate drops in regions of high foreground stellar crowding and extinction, and for low HI mass objects. Only 8% of all counterparts have a previous optical redshift measurement. The HI sources are found independently of Galactic extinction, although the detection rate drops in regions of high Galactic continuum. The survey is incomplete below a flux integral of approximately 3.1Jy/km/s and mean flux density of approximately 21mJy, with 75% and 81% of galaxies being above these limits, respectively. Taking into account dependence on both flux and velocity width, and constructing a scaled dependence on the flux integral limit with velocity width (w^0.74^), completeness limits of 2.8Jy/km/s and 17mJy are determined, with 92% of sources above these limits. A notable new galaxy is HIZOA J1353-58, a possible companion to the Circinus galaxy. Merging this catalog with the similarly conducted northern extension, large-scale structures are delineated, including those within the Puppis and Great Attractor regions and the Local Void. Several newly identified structures are revealed here for the first time. Three new galaxy concentrations (NW1, NW2, and NW3) are key in confirming the diagonal crossing of the Great Attractor Wall between the Norma Cluster and the CIZA J1324.7-5736 cluster. Further contributors to the general mass overdensity in that area are two new clusters (CW1 and CW2) in the nearer Centaurus Wall, one of which forms part of the striking 180{deg} (100h^-1^Mpc) long filament that dominates the southern sky at velocities of ~3000 km/s, and the suggestion of a further wall at the Great Attractor distance at slightly higher longitudes.
- ID:
- ivo://CDS.VizieR/I/220
- Title:
- The HST Guide Star Catalog, Version 1.1
- Short Name:
- I/220
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Guide Star Catalog (GSC), which has been constructed to support the operational need of the Hubble Space Telescope contains nearly 19 million objects brighter than sixteenth magnitude, of which more than 15 million are classified as stars. This catalog provides positions and magnitudes for these stars.
- ID:
- ivo://CDS.VizieR/I/254
- Title:
- The HST Guide Star Catalog, Version 1.2
- Short Name:
- I/254
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Guide Star Catalog (GSC), which has been constructed to support the operational need of the Hubble Space Telescope contains nearly 19 million objects brighter than sixteenth magnitude, of which more than 15 million are classified as stars. This catalog provides positions and magnitudes for these stars. The original version of this catalog, GSC 1.0, is described in a series of papers: Lasker et al. (1990AJ.....99.2019L); Russell et al. (1990AJ.....99.2059R); and Jenkner et al. (1990AJ.....99.2082J) The reference material for the GSC 1.2 reduction is the "Positions and Proper Motions Catalogue": PPM-North, Roeser S. and Bastian U., 1988, Cat. <I/146> PPM-South, Bastian U. and Roeser S., 1993, Cat. <I/193> PPM-Suppl, Roeser S., Bastian U. and Kuzmin A., 1994, Cat. <I/208> and the Astrographic Catalogue (AC) which was used to remove the mean systematics common to all the plates. The overall rms error of the GSC 1.2 is estimated better than 0.3arcsec The STScI provides the details of the GSC versions ("See also" section below) A binary version of the GSC1.2, with C code for querying, is available in the subdirectory GSC.
- ID:
- ivo://CDS.VizieR/I/255
- Title:
- The HST Guide Star Catalog, Version GSC-ACT
- Short Name:
- I/255
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Guide Star Catalog (GSC), which has been constructed to support the operational need of the Hubble Space Telescope contains nearly 19 million objects brighter than sixteenth magnitude, of which more than 15 million are classified as stars. This catalog provides positions and magnitudes for these stars. The original version of this catalog, GSC 1.0, is described in a series of papers: Lasker et al. (1990AJ.....99.2019L); Russell et al. (1990AJ.....99.2059R); and Jenkner et al. (1990AJ.....99.2082J) The reference material for the GSC 1.2 reduction is the "Positions and Proper Motions Catalogue": PPM-North, Roeser S. and Bastian U., 1988, Cat. <I/146> PPM-South, Bastian U. and Roeser S., 1993, Cat. <I/193> PPM-Suppl, Roeser S., Bastian U. and Kuzmin A., 1994, Cat. <I/208> and the Astrographic Catalogue (AC) which was used to remove the mean systematics common to all the plates. The GSC GSC-ACT is a recalibration of GSC1.1 using the ACT (Astrographic Catalog/Tycho, catalog <I/246>) performed by the Project Pluto ("See also" section below). The "plate RMS" values are given at http://www.projectpluto.com/results.txt, with most plates coming in at under .3 arcseconds