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1401. Photometric catalogs for ECDF-S and CDF-N
ID:
ivo://CDS.VizieR/J/ApJ/742/3
Title:
Photometric catalogs for ECDF-S and CDF-N
Short Name:
J/ApJ/742/3
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of deep multiwavelength data for z~0.3-3 starburst galaxies selected by their 70um emission in the Extended-Chandra Deep Field-South and Extended Groth Strip. We identify active galactic nuclei (AGNs) in these infrared sources through their X-ray emission and quantify the fraction that host an AGN. Lastly, we investigate the ratio between the supermassive black hole accretion rate (inferred from the AGN X-ray luminosity) and the bulge growth rate of the host galaxy (approximated as the SFR) and find that, for sources with detected AGNs and star formation (and neglecting systems with low star formation rates to which our data are insensitive), this ratio in distant starbursts agrees well with that expected from the local scaling relation assuming the black holes and bulges grew at the same epoch. These results imply that black holes and bulges grow together during periods of vigorous star formation and AGN activity.
1402. Photometric Classification Catalogue of SDSS DR7
ID:
ivo://CDS.VizieR/J/MNRAS/419/80
Title:
Photometric Classification Catalogue of SDSS DR7
Short Name:
J/MNRAS/419/80
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of about six million unresolved photometric detections in the Sloan Digital Sky Survey (SDSS) Seventh Data Release, classifying them into stars, galaxies and quasars. We use a machine learning classifier trained on a subset of spectroscopically confirmed objects from 14th to 22nd magnitude in the SDSS i band. Our catalogue consists of 2430625 quasars, 3544036 stars and 63586 unresolved galaxies from 14th to 24th magnitude in the SDSS i-band. Our algorithm recovers 99.96 per cent of spectroscopically confirmed quasars and 99.51 per cent of stars to i~21.3 in the colour window that we study. The level of contamination due to data artefacts for objects beyond i=21.3 is highly uncertain and all mention of completeness and contamination in the paper are valid only for objects brighter than this magnitude. However, a comparison of the predicted number of quasars with the theoretical number counts shows reasonable agreement.
1403. Photometric metallicities of stars in SkyMapper DR2
ID:
ivo://CDS.VizieR/J/ApJS/254/31
Title:
Photometric metallicities of stars in SkyMapper DR2
Short Name:
J/ApJS/254/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Milky Way's metal-poor stars are nearby ancient objects that are used to study early chemical evolution and the assembly and structure of the Milky Way. Here we present reliable metallicities of ~280000 stars with -3.75<~[Fe/H]<~-0.75 down to g=17 derived using metallicity-sensitive photometry from the second data release of the SkyMapper Southern Survey. We use the dependency of the flux through the SkyMapper v filter on the strength of the CaII K absorption features, in tandem with SkyMapper u, g, i photometry, to derive photometric metallicities for these stars. We find that metallicities derived in this way compare well to metallicities derived in large-scale spectroscopic surveys, and we use such comparisons to calibrate and quantify systematics as a function of location, reddening, and color. We find good agreement with metallicities from the APOGEE, LAMOST, and GALAH surveys, based on a standard deviation of {sigma}~0.25dex of the residuals of our photometric metallicities with respect to metallicities from those surveys. We also compare our derived photometric metallicities to metallicities presented in a number of high-resolution spectroscopic studies to validate the low-metallicity end ([Fe/H]{<}-2.5) of our photometric metallicity determinations. In such comparisons, we find the metallicities of stars with photometric [Fe/H]{<}-2.5 in our catalog show no significant offset and a scatter of {sigma}~0.31dex level relative to those in high-resolution work when considering the cooler stars (g-i>0.65) in our sample. We also present an expanded catalog containing photometric metallicities of ~720000 stars as a data table for further exploration of the metal-poor Milky Way.
1404. Photometric Redshift Catalog (SCUSS, SDSS, WISE)
ID:
ivo://CDS.VizieR/J/ApJ/862/12
Title:
Photometric Redshift Catalog (SCUSS, SDSS, WISE)
Short Name:
J/ApJ/862/12
Date:
21 Oct 2021
Publisher:
CDS
Description:
We publish a photometric redshift catalog based on imaging data of the South Galactic Cap u-band Sky Survey, Sloan Digital Sky Survey (SDSS), and Wide-field Infrared Survey Explorer (WISE). A total of 7 photometric bands are used, ranging from near ultraviolet to near infrared. A local linear regression method is adopted to estimate the photometric redshift with a dedicated spectroscopic training set. The photometric redshift catalog contains about 23.1 million galaxies classified by SDSS. Using the training set with redshift up to 0.8 and r-band magnitude down to 22mag, we achieve an average bias of {Delta}z_norm_=0.000228, standard deviation of {sigma}({Delta}z_norm_)=0.019, and 3{sigma} outlier rate of about 4.2%. The bias is less than 0.01 at z<0.6 and goes up to about 0.05 at z~0.8. Compared with SDSS photometric redshifts, our redshift estimations are more accurate and have less bias.
1405. Photometric redshift of AGNs from XMM- and C-COSMOS
ID:
ivo://CDS.VizieR/J/ApJ/742/61
Title:
Photometric redshift of AGNs from XMM- and C-COSMOS
Short Name:
J/ApJ/742/61
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper, we release accurate photometric redshifts for 1692 counterparts to Chandra sources in the central square degree of the Cosmic Evolution Survey (COSMOS) field. The availability of a large training set of spectroscopic redshifts that extends to faint magnitudes enabled photometric redshifts comparable to the highest quality results presently available for normal galaxies. We demonstrate that morphologically extended, faint X-ray sources without optical variability are more accurately described by a library of normal galaxies (corrected for emission lines) than by active galactic nucleus (AGN) dominated templates, even if these sources have AGN-like X-ray luminosities. Preselecting the library on the bases of the source properties allowed us to reach an accuracy {sigma}_{Delta}z_/(1+z_spec_)~0.015 with a fraction of outliers of 5.8% for the entire Chandra-COSMOS sample. In addition, we release revised photometric redshifts for the 1735 optical counterparts of the XMM-detected sources over the entire 2deg^2^ of COSMOS. For 248 sources, our updated photometric redshift differs from the previous release by {Delta}z>0.2. These changes are predominantly due to the inclusion of newly available deep H-band photometry (H_AB_=24mag).
1406. Photometric redshifts in the Hawaii-HDF-N
ID:
ivo://CDS.VizieR/J/ApJS/215/27
Title:
Photometric redshifts in the Hawaii-HDF-N
Short Name:
J/ApJS/215/27
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive photometric redshifts (z_phot_) for sources in the entire (~0.4deg^2^) Hawaii-Hubble Deep Field-North (H-HDF-N) field with the EAzY code, based on point-spread-function-matched photometry of 15 broad bands from the ultraviolet (U band) to mid-infrared (IRAC 4.5{mu}m). Our catalog consists of a total of 131678 sources. We evaluate the z_phot_ quality by comparing z_phot_with spectroscopic redshifts (z_spec_) when available, and find a value of normalized median absolute deviation {sigma}_NMAD_=0.029 and an outlier fraction of 5.5% (outliers are defined as sources having |z_phot_-z_spec_|/(1+z_spec_)>0.15) for non-X-ray sources. More specifically, we obtain {sigma}_NMAD_=0.024 with 2.7% outliers for sources brighter than R=23mag, {sigma}_NMAD_=0.035 with 7.4% outliers for sources fainter than R=23mag, {sigma}_NMAD_=0.026 with 3.9% outliers for sources having z<1, and {sigma}_NMAD_=0.034 with 9.0% outliers for sources having z>1. Our z_phot_ quality shows an overall improvement over an earlier z_phot_ work that focused only on the central H-HDF-N area. We also classify each object as a star or galaxy through template spectral energy distribution fitting and complementary morphological parameterization, resulting in 4959 stars and 126719 galaxies. Furthermore, we match our catalog with the 2Ms Chandra Deep Field-North main X-ray catalog. For the 462 matched non-stellar X-ray sources (281 having z_spec_), we improve their z_phot_ quality by adding three additional active galactic nucleus templates, achieving {sigma}_NMAD_=0.035 and an outlier fraction of 12.5%.
1407. Photometric survey of MS 1054-03 field
ID:
ivo://CDS.VizieR/J/AJ/131/1891
Title:
Photometric survey of MS 1054-03 field
Short Name:
J/AJ/131/1891
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep near-infrared Js-, H-, and Ks-band imaging of a field around MS 1054-03, a massive cluster at z=0.83. The observations were carried out with the ISAAC instrument at the ESO Very Large Telescope (VLT) as part of the Faint Infrared Extragalactic Survey (FIRES). The total integration time amounts to 25.9hr in Js, 24.4hr in H, and 26.5hr in Ks, divided nearly equally between four pointings covering 5.5'x5.3'. The 3 total limiting AB magnitudes for point sources from the shallowest to the deepest pointing are J^tot^_s,AB_=26.0-26.2, H^tot^_AB_=25.5-25.8, and K^tot^_s,AB_=25.3-25.7mag. The effective spatial resolution of the co-added images has FWHM=0.48", 0.46", and 0.52" in Js, H, and Ks, respectively. We complemented the ISAAC data with deep optical imaging using existing Hubble Space Telescope WFPC2 mosaics through the F606W and F814W filters and additional U-, B-, and V-band observations we obtained with the VLT FORS1 instrument. We constructed a Ks-band-limited multicolor source catalog down to K^tot^_s,AB_~25mag (~5{sigma} for point sources). The catalog contains 1858 objects, of which 1663 have eight-band photometry. We describe the observations, data reduction, source detection, and photometric measurements method. We also present the number counts, color distributions, and photometric redshifts zph of the catalog sources. We find that our Ks-band counts at the faint end 22<~K_s,AB_<~25, with slope dlogN/dm=0.20, lie at the flatter end of published counts in other deep fields and are consistent with those we derived previously in the Hubble Deep Field-South (HDF-S), the other FIRES field. Spectroscopic redshifts zsp are available for ~330 sources in the MS 1054-03 field; comparison between zph and zsp shows very good agreement, with <|zsp-zph|/(1+zsp)>=0.078. The MS 1054-03 field observations complement our HDF-S data set with a nearly 5 times larger area at ~0.7mag brighter limits, providing more robust statistics for the slightly brighter source populations.
1408. Photometry catalogs for the Lockman Hole
ID:
ivo://CDS.VizieR/J/ApJS/198/1
Title:
Photometry catalogs for the Lockman Hole
Short Name:
J/ApJS/198/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present broadband photometry and photometric redshifts for 187611 sources located in ~0.5deg^2^ in the Lockman Hole area. The catalog includes 388 X-ray-detected sources identified with the very deep XMM-Newton observations available for an area of 0.2deg^2^. The source detection was performed on the Rc-, z'-, and B-band images and the available photometry is spanning from the far-ultraviolet to the mid-infrared, reaching in the best-case scenario 21 bands. Astrometry corrections and photometric cross-calibrations over the entire data set allowed the computation of accurate photometric redshifts. Special treatment is undertaken for the X-ray sources, the majority of which are active galactic nuclei (AGNs). For normal galaxies, comparing the photometric redshifts to the 253 available spectroscopic redshifts, we achieve an accuracy of {sigma}_{Delta}z/(1+z)_=0.036, with 12.6% outliers. For the X-ray-detected sources, compared to 115 spectroscopic redshifts, the accuracy is {sigma}_{Delta}z/(1+z)_=0.069, with 18.3% outliers, where the outliers are defined as sources with |z_phot_-z_spec_|>0.15x(1+z_spec_).
1409. Photometry monitoring of the SN PTF10vdl
ID:
ivo://CDS.VizieR/J/ApJ/736/159
Title:
Photometry monitoring of the SN PTF10vdl
Short Name:
J/ApJ/736/159
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Palomar Transient Factory (PTF) is an optical wide-field variability survey carried out using a camera with a 7.8deg^2^ field of view mounted on the 48 inch Oschin Schmidt telescope at Palomar Observatory. One of the key goals of this survey is to conduct high-cadence monitoring of the sky in order to detect optical transient sources shortly after they occur. Here, we describe the real-time capabilities of the PTF and our related rapid multiwavelength follow-up programs, extending from the radio to the {gamma}-ray bands. We present as a case study observations of the optical transient PTF10vdl (SN 2010id), revealed to be a very young core-collapse (Type II-P) supernova having a remarkably low luminosity. Our results demonstrate that the PTF now provides for optical transients the real-time discovery and rapid-response follow-up capabilities previously reserved only for high-energy transients like gamma-ray bursts.
1410. Photometry of RR Lyrae candidates in Virgo stream
ID:
ivo://CDS.VizieR/J/ApJ/691/306
Title:
Photometry of RR Lyrae candidates in Virgo stream
Short Name:
J/ApJ/691/306
Date:
21 Oct 2021
Publisher:
CDS
Description:
A subset of the RR Lyrae (RRL) candidates identified from the Southern Edgeworth-Kuiper Belt Object (SEKBO) survey data have been followed up photometrically (n=106) and spectroscopically (n=51). Period and light curve fitting reveals a 24+/-7% contamination of SEKBO survey data by non-RRLs. This paper focuses on the region of the Virgo Stellar Stream (VSS), particularly on its extension to the south of the declination limits of the Sloan Digital Sky Survey and of the Quasar Equatorial Survey Team (QUEST) RRL survey.

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