- ID:
- ivo://CDS.VizieR/J/ApJS/179/1
- Title:
- The OPTX project: CLANS, CLASXS and CDF-N
- Short Name:
- J/ApJS/179/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the redshift catalogs for the X-ray sources detected in the Chandra Deep Field-North (CDF-N), the Chandra Large Area Synoptic X-ray Survey (CLASXS), and the Chandra Lockman Area North Survey (CLANS). The catalogs for the CDF-N and CLASXS fields include redshifts from previous work, while the redshifts for the CLANS field are all new. For fluxes above 10^-14^ergs/cm^2^/s (2-8keV) we have redshifts for 76% of the sources. We extend the redshift information for the full sample using photometric redshifts. The goal of the OPTX Project is to use these three surveys, which are among the most spectroscopically complete surveys to date, to analyze the effect of spectral type on the shape and evolution of the X-ray luminosity functions and to compare the optical spectral types with the X-ray spectral properties. We also present the CLANS X-ray catalog. The nine ACIS-I fields cover a solid angle of ~0.6deg^2^ and reach fluxes of 7x10^-16^ergs/cm^2^/s (0.5-2keV) and 3.5x10^-15^ergs/cm^2^/s (2-8keV). We find a total of 761 X-ray point sources. In addition, we present the optical and infrared photometric catalog for the CLANS X-ray sources, as well as updated optical and infrared photometric catalogs for the X-ray sources in the CLASXS and CDF-N fields.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/245/6
- Title:
- The 2RMS catalog in the Zone of Avoidance
- Short Name:
- J/ApJS/245/6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Two Micron All-Sky Survey (2MASS) Redshift Survey was started two decades ago with the goal of mapping the three-dimensional distribution of an all-sky flux-limited (Ks<11.75mag) sample of ~45000 galaxies. Our first data release presented an unprecedented uniform coverage for most of the celestial sphere, with redshifts for ~98% of our sample. However, we were missing redshifts for ~18% of the catalog entries that were located within the "Zone of Avoidance" (|b|<10{deg})-an important region of the sky for studies of the large-scale structure and cosmic flows. In this second and final data release, we present redshifts for all 1041 2MRS galaxies that previously lacked this information, as well as updated measurements for 27 others.
- ID:
- ivo://CDS.VizieR/J/ApJS/241/34
- Title:
- The SDSS Reverberation Mapping (SDSS-RM) project
- Short Name:
- J/ApJS/241/34
- Date:
- 07 Mar 2022 07:38:42
- Publisher:
- CDS
- Description:
- We present a detailed characterization of the 849 broad-line quasars from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project. Our quasar sample covers a redshift range of 0.1<z<4.5 and is flux-limited to i_PSF_<21.7 without any other cuts on quasar properties. The main sample characterization includes: (1) spectral measurements of the continuum and broad emission lines for individual objects from the coadded first-season spectroscopy in 2014, (2) identification of broad and narrow absorption lines in the spectra, and (3) optical variability properties for continuum and broad lines from multi-epoch spectroscopy. We provide improved systemic redshift estimates for all quasars and demonstrate the effects of the signal-to-noise ratio on the spectral measurements. We compile measured properties for all 849 quasars along with supplemental multi-wavelength data for subsets of our sample from other surveys. The SDSS-RM sample probes a diverse range in quasar properties and shows well-detected continuum and broad-line variability for many objects from first-season monitoring data. The compiled properties serve as the benchmark for follow-up work based on SDSS-RM data.
- ID:
- ivo://CDS.VizieR/J/ApJ/716/348
- Title:
- The XMM-Newton survey of the COSMOS field
- Short Name:
- J/ApJ/716/348
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the final optical identifications of the medium-depth (~60ks), contiguous (2deg^2^) XMM-Newton survey of the COSMOS field. XMM-Newton has detected ~1800 X-ray sources down to limiting fluxes of ~5x10^-16^, ~3x10^-15^, and ~7x10^-15^erg/cm^2^/s in the 0.5-2keV, 2-10keV, and 5-10keV bands, respectively (~1x10^-15^, ~6x10^-15^, and ~1x10^-14^erg/cm^2^/s, in the three bands, respectively, over 50% of the area). The work is complemented by an extensive collection of multiwavelength data from 24um to UV, available from the COSMOS survey, for each of the X-ray sources, including spectroscopic redshifts for >~50% of the sample, and high-quality photometric redshifts for the rest. The XMM and multiwavelength flux limits are well matched: 1760 (98%) of the X-ray sources have optical counterparts, 1711 (~95%) have IRAC counterparts, and 1394 (~78%) have MIPS 24um detections. Spectroscopically identified obscured and unobscured AGNs, as well as normal and star-forming galaxies, present well-defined optical and infrared properties. We devised a robust method to identify a sample of ~150 high-redshift (z>1), obscured AGN candidates for which optical spectroscopy is not available.
- ID:
- ivo://CDS.VizieR/J/ApJ/799/208
- Title:
- Type IIP supernovae from Pan-STARRS1
- Short Name:
- J/ApJ/799/208
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In recent years, wide-field sky surveys providing deep multiband imaging have presented a new path for indirectly characterizing the progenitor populations of core-collapse supernovae (SNe): systematic light-curve studies. We assemble a set of 76 grizy-band Type IIP SN light curves from Pan-STARRS1, obtained over a constant survey program of 4yr and classified using both spectroscopy and machine-learning-based photometric techniques. We develop and apply a new Bayesian model for the full multiband evolution of each light curve in the sample. We find no evidence of a subpopulation of fast-declining explosions (historically referred to as "Type IIL" SNe). However, we identify a highly significant relation between the plateau phase decay rate and peak luminosity among our SNe IIP. These results argue in favor of a single parameter, likely determined by initial stellar mass, predominantly controlling the explosions of red supergiants. This relation could also be applied for SN cosmology, offering a standardizable candle good to an intrinsic scatter of <~0.2mag. We compare each light curve to physical models from hydrodynamic simulations to estimate progenitor initial masses and other properties of the Pan-STARRS1 Type IIP SN sample. We show that correction of systematic discrepancies between modeled and observed SN IIP light-curve properties and an expanded grid of progenitor properties are needed to enable robust progenitor inferences from multiband light-curve samples of this kind. This work will serve as a pathfinder for photometric studies of core-collapse SNe to be conducted through future wide-field transient searches.
- ID:
- ivo://CDS.VizieR/J/AJ/128/544
- Title:
- UBRI Photometry of Quasars
- Short Name:
- J/AJ/128/544
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present UBRI photometry and spectra for 60 quasars found within 1{deg}^2^ centered on the J0053+1234 region, which has been the subject of the Caltech Faint Galaxy Redshift Survey. Candidate quasars were selected by their ultraviolet excess with respect to the stellar locus and confirmed spectroscopically. The quasars span a wide range in brightness (17.5<B<21.6) and redshift (0.43<z<2.38).
- ID:
- ivo://CDS.VizieR/J/AJ/121/2381
- Title:
- UBRI photometry of radio galaxies
- Short Name:
- J/AJ/121/2381
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a new estimate of the radio galaxy 1.4 GHz luminosity function and its evolution at intermediate redshifts (z~0.4). Photometric redshifts and color selection have been used to select B_J_<23.5 early-type galaxies from the Panoramic Deep Fields, a multicolor survey of two 25deg^2^ fields. Approximately 230 radio galaxies have then been selected by matching early-type galaxies with NVSS radio sources brighter than 5mJy. Estimates of the 1.4GHz luminosity function of radio galaxies measure significant evolution over the observed redshift range. For an {Omega}_M_=1 cosmology the evolution of the radio power is consistent with luminosity evolution where P(z)~P(0)(1+z)^K_L_^ and 3<K_L_<5. The observed evolution is similar to that observed for UVX and X-ray selected active galactic nuclei and is consistent with the same physical process being responsible for the optical and radio luminosity evolution of active galactic nuclei.
- ID:
- ivo://CDS.VizieR/J/AJ/126/632
- Title:
- UBVRIz'HK' photometry of 2Ms CDFN X-ray sources
- Short Name:
- J/AJ/126/632
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an optical and near-infrared catalog for the X-ray sources in the 2Ms Chandra observation of the Hubble Deep Field North region. We have high-quality multicolor imaging data for all 503 X-ray point sources in the X-ray-selected catalog and reliable spectroscopic redshifts for 284. We spectroscopically identify six high-redshift (z>1) type II quasars (L_2-8keV_>10^44^ergs/s) in our sample. Our spectroscopic completeness for the R<=24 sources is 87%. The spectroscopic redshift distribution shows two broad redshift spikes that have clearly grown over those originally seen in the 1Ms exposure. The spectroscopically identified extragalactic sources already comprise 75% of the measured 2-8keV light. Redshift slices versus 2-8keV flux show that an impressive 54% of the measured 2-8keV light arises from sources at z<1 and 68% from sources at z<2.
- ID:
- ivo://CDS.VizieR/J/AJ/151/33
- Title:
- UBVRIz light curves of 51 Type II supernovae
- Short Name:
- J/AJ/151/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a compilation of UBVRIz light curves of 51 type II supernovae discovered during the course of four different surveys during 1986-2003: the Cerro Tololo Supernova Survey, the Calan/Tololo Supernova Program (C&T), the Supernova Optical and Infrared Survey (SOIRS), and the Carnegie Type II Supernova Survey (CATS). The photometry is based on template-subtracted images to eliminate any potential host galaxy light contamination, and calibrated from foreground stars. This work presents these photometric data, studies the color evolution using different bands, and explores the relation between the magnitude at maximum brightness and the brightness decline parameter (s) from maximum light through the end of the recombination phase. This parameter is found to be shallower for redder bands and appears to have the best correlation in the B band. In addition, it also correlates with the plateau duration, being shorter (longer) for larger (smaller) s values.
- ID:
- ivo://CDS.VizieR/J/ApJ/778/127
- Title:
- UKIDSS+FIRST+SDSS red QSOs candidates
- Short Name:
- J/ApJ/778/127
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a pilot survey to find dust-reddened quasars by matching the Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) radio catalog to the UKIDSS near-infrared survey and using optical data from Sloan Digital Sky Survey to select objects with very red colors. The deep K-band limit provided by UKIDSS allows for finding more heavily reddened quasars at higher redshifts as compared with previous work using FIRST and Two Micron All Sky Survey (2MASS). We selected 87 candidates with K<=17.0 from the UKIDSS Large Area Survey (LAS) First Data Release (DR1), which covers 190deg^2^. These candidates reach up to ~1.5mag below the 2MASS limit and obey the color criteria developed to identify dust-reddened quasars. We have obtained 61 spectroscopic observations in the optical and/or near-infrared, as well as classifications in the literature, and have identified 14 reddened quasars with E(B-V)>0.1, including 3 at z>2. We study the infrared properties of the sample using photometry from the Wide-Field Infrared Survey Explorer and find that infrared colors improve the efficiency of red quasar selection, removing many contaminants in an infrared-to-optical color-selected sample alone. The highest-redshift quasars (z>~2) are only moderately reddened, with E(B-V)~0.2-0.3. We find that the surface density of red quasars rises sharply with faintness, comprising up to 17% of blue quasars at the same apparent K-band flux limit. We estimate that to reach more heavily reddened quasars (i.e., E(B-V)>~0.5) at z>2 and a depth of K=17, we would need to survey at least ~2.5 times more area.