122,065 research outputs found
HFF-DeepSpace photometric catalogs of the 12 Hubble frontier fields, clusters, and parallels : photometry, photometric redshifts, and stellar masses
We present Hubble multi-wavelength photometric catalogs, including (up to) 17 filters with the Advanced Camera for Surveys and Wide Field Camera 3 from the ultra-violet to near-infrared for the Hubble Frontier Fields and associated parallels. We have constructed homogeneous photometric catalogs for all six clusters and their parallels. To further expand these data catalogs, we have added ultra-deep KS-band imaging at 2.2. mu m from the Very Large Telescope HAWK-I and Keck-I MOSFIRE instruments. We also add post-cryogenic Spitzer imaging at 3.6 and 4.5. mu m with the Infrared Array Camera (IRAC), as well as archival IRAC 5.8 and 8.0. mu m imaging when available. We introduce the public release of the multi-wavelength (0.2-8 mu m) photometric catalogs, and we describe the unique steps applied for the construction of these catalogs. Particular emphasis is given to the source detection band, the contamination of light from the bright cluster galaxies (bCGs), and intra-cluster light (ICL). In addition to the photometric catalogs, we provide catalogs of photometric redshifts and stellar population properties. Furthermore, this includes all the images used in the construction of the catalogs, including the combined models of bCGs and ICL, the residual images, segmentation maps, and more. These catalogs are a robust data set of the Hubble Frontier Fields and will be an important aid in designing future surveys, as well as planning follow-up programs with current and future observatories to answer key questions remaining about first light, reionization, the assembly of galaxies, and many more topics, most notably by identifying high-redshift sources to target
The WISE AGN Catalog
We present two large catalogs of AGN candidates identified across ~75% of the
sky from the Wide-field Infrared Survey Explorer's AllWISE Data Release. Both
catalogs, some of the largest such catalogs published to date, are selected
purely on the basis of mid-IR photometry in the WISE W1 and W2 bands. The
catalogs are designed to be appropriate for a broad range of scientific
investigations, with one catalog emphasizing reliability while the other
emphasizes completeness. Specifically, the R90 catalog consists of 4,543,530
AGN candidates with 90% reliability, while the C75 catalog consists of
20,907,127 AGN candidates with 75% completeness. We provide a detailed
discussion of potential artifacts, and excise portions of the sky close to the
Galactic Center, Galactic Plane, nearby galaxies, and other expected
contaminating sources. Our final catalogs cover 30,093 deg^2 of extragalactic
sky. These catalogs are expected to enable a broad range of science, and we
present a few simple illustrative cases. From the R90 sample we identify 45
highly variable AGN lacking radio counterparts in the FIRST survey, implying
they are unlikely to be blazars. One of these sources, WISEA
J142846.71+172353.1, is a mid-IR-identified changing-look quasar at z=0.104. We
characterize our catalogs by comparing them to large, wide-area AGN catalogs in
the literature, specifically UV-to-near-IR quasar selections from SDSS and
XDQSOz, mid-IR selection from Secrest et al. (2015) and X-ray selection from
ROSAT. From the latter work, we identify four ROSAT X-ray sources that each are
matched to three WISE-selected AGN in the R90 sample within 30". Palomar
spectroscopy reveals one of these systems, 2RXS J150158.6+691029, to consist of
a triplet of quasars at z=1.133 +/- 0.004, suggestive of a rich group or
forming galaxy cluster.(Abridged)Comment: Accepted for publication in the Astrophysical Journal Supplements.
Updated with comments from the referee. 20 pages, 15 figures, 8 tables. The
WISE AGN Catalogs can be made available upon request by writing to
[email protected]
Re-calibration of SDF/SXDS Photometric Catalogs of Suprime-Cam with SDSS Data Release 8
We present photometric recalibration of the Subaru Deep Field (SDF) and
Subaru/XMM-Newton Deep Survey (SXDS). Recently, Yamanoi et al. (2012) suggested
the existence of a discrepancy between the SDF and SXDS catalogs. We have used
the Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8) catalog and compared
stars in common between SDF/SXDS and SDSS. We confirmed that there exists a
0.12 mag offset in B-band between the SDF and SXDS catalogs. Moreover, we found
that significant zero point offsets in i-band (~ 0.10 mag) and z-band (~ 0.14
mag) need to be introduced to the SDF/SXDS catalogs to make it consistent with
the SDSS catalog. We report the measured zero point offsets of five filter
bands of SDF/SXDS catalogs. We studied the potential cause of these offsets,
but the origins are yet to be understood.Comment: 36 pages, 19 figures(128 EPS files), PASJ accepte
K2: A new method for the detection of galaxy clusters based on CFHTLS multicolor images
We have developed a new method, K2, optimized for the detection of galaxy
clusters in multicolor images. Based on the Red Sequence approach, K2 detects
clusters using simultaneous enhancements in both colors and position. The
detection significance is robustly determined through extensive Monte-Carlo
simulations and through comparison with available cluster catalogs based on two
different optical methods, and also on X-ray data. K2 also provides
quantitative estimates of the candidate clusters' richness and photometric
redshifts. Initially K2 was applied to 161 sq deg of two color gri images of
the CFHTLS-Wide data. Our simulations show that the false detection rate, at
our selected threshold, is only ~1%, and that the cluster catalogs are ~80%
complete up to a redshift of 0.6 for Fornax-like and richer clusters and to z
~0.3 for poorer clusters. Based on Terapix T05 release gri photometric
catalogs, 35 clusters/sq deg are detected, with 1-2 Fornax-like or richer
clusters every two square degrees. Catalogs containing data for 6144 galaxy
clusters have been prepared, of which 239 are rich clusters. These clusters,
especially the latter, are being searched for gravitational lenses -- one of
our chief motivations for cluster detection in CFHTLS. The K2 method can be
easily extended to use additional color information and thus improve overall
cluster detection to higher redshifts. The complete set of K2 cluster catalogs,
along with the supplementary catalogs for the member galaxies, are available on
request from the authors.Comment: Accepted in ApJ. 25 pages, including 10 figures. Latex with
emulateapj v03/07/0
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