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621. COSMOS/UltraVISTA Ks-selected catalogs v4.1
ID:
ivo://CDS.VizieR/J/ApJS/206/8
Title:
COSMOS/UltraVISTA Ks-selected catalogs v4.1
Short Name:
J/ApJS/206/8
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog covering 1.62deg^2^ of the COSMOS/UltraVISTA field with point-spread function (PSF) matched photometry in 30 photometric bands. The catalog covers the wavelength range 0.15-24{mu}m including the available GALEX, Subaru, Canada-France-Hawaii Telescope, VISTA, and Spitzer data. Catalog sources have been selected from the DR1 UltraVISTA K_s_ band imaging that reaches a depth of K_s,tot_=23.4 AB (90% completeness). The PSF-matched catalog is generated using position-dependent PSFs ensuring accurate colors across the entire field. Also included is a catalog of photometric redshifts (z_phot_) for all galaxies computed with the EAZY code. Comparison with spectroscopy from the zCOSMOS 10k bright sample shows that up to z~1.5 the z_phot_ are accurate to {Delta}z/(1+z)=0.013, with a catastrophic outlier fraction of only 1.6%. The z_phot_ also show good agreement with the z_phot_ from the NEWFIRM Medium Band Survey out to z~3. A catalog of stellar masses and stellar population parameters for galaxies determined using the FAST spectral energy distribution fitting code is provided for all galaxies. Also included are rest-frame U-V and V-J colors, L_2800_ and L_IR_. The UVJ color-color diagram confirms that the galaxy bi-modality is well-established out to z~2. Star-forming galaxies also obey a star-forming "main sequence" out to z~2.5, and this sequence evolves in a manner consistent with previous measurements. The COSMOS/UltraVISTA K_s_-selected catalog covers a unique parameter space in both depth, area, and multi-wavelength coverage and promises to be a useful tool for studying the growth of the galaxy population out to z~3-4.
622. COSMOS 70um sources
ID:
ivo://CDS.VizieR/J/ApJ/709/572
Title:
COSMOS 70um sources
Short Name:
J/ApJ/709/572
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a large robust sample of 1503 reliable and unconfused 70um selected sources from the multiwavelength data set of the Cosmic Evolution Survey. Using the Spitzer IRAC and MIPS photometry, we estimate the total infrared (IR) luminosity, LIR (8-1000um), by finding the best-fit template from several different template libraries. The long-wavelength 70 and 160um data allow us to obtain a reliable estimate of LIR, accurate to within 0.2 and 0.05dex, respectively. The 70um data point enables a significant improvement over the luminosity estimates possible with only a 24um detection. The full sample spans a wide range in IR luminosity, LIR~10^8^-10^14^L_{sun}_, with a median luminosity of 10^11.4^L_{sun}_. We identify a total of 687 luminous, 303 ultraluminous, and 31 hyperluminous infrared galaxies (LIRGs, ULIRGs, and HyLIRGs) over the redshift range 0.01<z<3.5 with a median redshift of 0.5. Presented here are the full spectral energy distributions (SEDs) for each of the sources compiled from the extensive multiwavelength data set from the ultraviolet (UV) to the far-infrared. A catalog of the general properties of the sample (including the photometry, redshifts, and LIR) is included with this paper.
623. Counterparts to 1.4GHz sources in ECDF-S
ID:
ivo://CDS.VizieR/J/ApJS/203/15
Title:
Counterparts to 1.4GHz sources in ECDF-S
Short Name:
J/ApJS/203/15
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study a sample of 883 sources detected in a deep Very Large Array survey at 1.4GHz in the Extended Chandra Deep Field South. This paper focuses on the identification of their optical and infrared (IR) counterparts. We use a likelihood-ratio technique that is particularly useful when dealing with deep optical images to minimize the number of spurious associations. We find a reliable counterpart for 95% of our radio sources. Most of the counterparts (74%) are detected at optical wavelengths, but there is a significant fraction (21%) that are only detectable in the IR. Combining newly acquired optical spectra with data from the literature, we are able to assign a redshift to 81% of the identified radio sources (37% spectroscopic). We also investigate the X-ray properties of the radio sources using the Chandra 4Ms and 250ks observations. In particular, we use a stacking technique to derive the average properties of radio objects undetected in the Chandra images. The results of our analysis are collected in a new catalog containing the position of the optical/IR counterpart, the redshift information, and the X-ray fluxes. It is the deepest multi-wavelength catalog of radio sources, which will be used for future study of this galaxy population.
624. Cousins RI photometry in IC 348
ID:
ivo://CDS.VizieR/J/AJ/127/1602
Title:
Cousins RI photometry in IC 348
Short Name:
J/AJ/127/1602
Date:
21 Oct 2021
Publisher:
CDS
Description:
The extremely young cluster IC 348 has been monitored photometrically over five observing seasons from 1998 December 10 to 2003 March 26 in Cousins I with a 0.6m telescope at Van Vleck Observatory. Twenty-eight periodic variables and 16 irregular variables have been identified. The variability study is most sensitive for stars with I<14.3mag; at that brightness level, we find that 24 of the 27 known pre-main-sequence (PMS) cluster members in the monitored field are variables, illustrating the value of photometric monitoring for identifying PMS cluster members. Among this brighter sample, 14 of the 16 known K or M-type weak-line T Tauri stars (WTTS) were found to be periodic variables, while all five of the known classical T Tauri stars (CTTS) were found to be irregular variables. In the full sample, which includes 150 stars with I as faint as 18, we find that 40% of the 63 WTTS are detected as variables, nearly all of them periodic, while 55% of the 20 CTTS are also detected as variable, with none of them periodic.
625. Cousins RI photometry of NGC 2169
ID:
ivo://CDS.VizieR/J/MNRAS/376/580
Title:
Cousins RI photometry of NGC 2169
Short Name:
J/MNRAS/376/580
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have used Cousins RI CCD photometry from the Isaac Newton telescope and intermediate-resolution spectroscopy from the Gemini North telescope to identify and characterize low-mass (0.15<M/M_{sun}_<1.3) pre-main-sequence stars in the young open cluster NGC 2169. Isochrone fitting to the high- and low-mass populations yields an intrinsic distance modulus of 10.13^+0.06^_-0.09_mag and a model-dependent age of 9+/-2Myr. Compared to the nearby, kinematically defined groups of a similar age, NGC 2169 has a large low-mass population which potentially offers a more precise statistical investigation of several aspects of star formation and early stellar evolution. By modelling the distribution of low-mass stars in the IC versus RC IC diagram, we find that any age spread among cluster members has a Gaussian full width at half-maximum (FWHM) 2.5Myr. A young age and a small age spread (<10Myr) are supported by the lack of significant lithium depletion in the vast majority of cluster members. There is no clear evidence for accretion or warm circumstellar dust in the low-mass members of NGC 2169, bolstering the idea that strong accretion has ceased and inner discs have dispersed in almost all low-mass stars by ages of 10Myr.
626. Cr, Co, and Ni abundances for metal-poor red giants
ID:
ivo://CDS.VizieR/J/ApJS/237/18
Title:
Cr, Co, and Ni abundances for metal-poor red giants
Short Name:
J/ApJS/237/18
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present measurements of the abundances of chromium, cobalt, and nickel in 4113 red giants, including 2277 stars in globular clusters (GCs), 1820 stars in the Milky Way's dwarf satellite galaxies, and 16 field stars. We measured the abundances from mostly archival Keck/DEIMOS medium-resolution spectroscopy with a resolving power of R~6500 and a wavelength range of approximately 6500-9000{AA}. The abundances were determined by fitting spectral regions that contain absorption lines of the elements under consideration. We used estimates of temperature, surface gravity, and metallicity that we previously determined from the same spectra. We estimated systematic error by examining the dispersion of abundances within mono- metallic GCs. The median uncertainties for [Cr/Fe], [Co/Fe], and [Ni/Fe] are 0.20, 0.20, and 0.13, respectively. Finally, we validated our estimations of uncertainty through duplicate measurements, and we evaluated the accuracy and precision of our measurements through comparison to high-resolution spectroscopic measurements of the same stars.
627. C star population in outer disk of M31
ID:
ivo://CDS.VizieR/J/A+A/436/91
Title:
C star population in outer disk of M31
Short Name:
J/A+A/436/91
Date:
21 Oct 2021
Publisher:
CDS
Description:
We employ the CFHT Megacam camera to survey ~1{deg}^2^ of the southern outer disc of M31, a region which includes the area where Battinelli et al. (2003, Cat. <J/AJ/125/1298>) have identified nearly one thousand C stars. In the outer M31 region not previously surveyed, we identify 361 new C star candidates, having similar photometric properties to the known ones, and confirm the slight decrease in the luminosity of C stars with galactocentric distances. We show that the Sloan g', r', i' filters are a viable approach, comparable to (CN-TiO), to identify C stars. We find that the (g'-r') colours of cool C stars can be so red that prohibitively long g' exposures are needed to acquire faint extragalactic C stars. This makes the Sloan filters a less promising approach to extend a C star survey to several Mpc. Our uniform large field survey detects the edge of M31 disk at ~35kpc. The intermediate-age population, represented by C stars, extends further to ~40kpc.
628. C star population in outer disk of M31
ID:
ivo://CDS.VizieR/J/AJ/125/1298
Title:
C star population in outer disk of M31
Short Name:
J/AJ/125/1298
Date:
21 Oct 2021
Publisher:
CDS
Description:
We employ the CFH12K mosaic to identify carbon stars, using the R, I, CN, and TiO photometric technique, in a 2240 arcmin2 area, ranging from 17 to 30kpc of the southwest disk of M31, barely reaching the edge of the observed H I disk. We found 945 C stars with <I_0_>=19.94mag and {sigma}=0.47. The surface density of C stars along the major axis of M31 follows an exponential profile with a scale length of 4.85+/-0.35kpc, in agreement with adopted values for the scale length of the disk population. Our survey partially overlaps with the recently discovered G1 density enhancement by Ferguson et al. We confirm that no AGB star excess is detectable in the surveyed part of the clump. The C/M ratio, along the major axis, is derived over a distance range of 7kpc. The strong C/M gradient seen contrasts with results of previous studies of the C stars in M31.
629. C stars in IC 1613
ID:
ivo://CDS.VizieR/J/AJ/119/2780
Title:
C stars in IC 1613
Short Name:
J/AJ/119/2780
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of a multifilter survey of the whole Magellanic-type galaxy IC 1613. Narrowband CN and TiO filters are used to identify carbon stars among red giants. We have identified 195 carbon stars, extending up to 15' from the center of the galaxy. We present well-calibrated R and I magnitudes for all stars. The large field surveyed allows a reliable foreground estimate of M stars, leading to a C/M ratio of 0.64, when giants as early as M0 are counted. Analysis of the photometric properties of the C star population reveals a narrow M_I_ distribution with a mean M_I_ of -4.69mag, with a dispersion of +/-0.28. IC 1613 has, for its absolute magnitude, a normal number of C stars.
630. C stars in Pegasus, DDO 210 and Tucana
ID:
ivo://CDS.VizieR/J/AJ/120/1801
Title:
C stars in Pegasus, DDO 210 and Tucana
Short Name:
J/AJ/120/1801
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the latest results of our ongoing four-filter photometric survey of C stars in Local Group dwarf irregular galaxies. Observations of the two low-luminosity dwarf irregular galaxies, Pegasus and DDO 210, revealed 40 and three C stars, respectively, assuming that the reddening of Pegasus is negligible. No C stars were identified in Tucana. Our observations permit the estimation of the color-magnitude diagram contamination by foreground M dwarfs thus yielding reliable C/M ratios. Our R and I photometry of the C stars cannot be used to solve the extinction controversy toward Pegasus. The three C stars in DDO 210 are quite bright when compared with C star populations in other dwarf galaxies. A larger, fainter population in that galaxy seems improbable, however. The statistics of C stars currently on hand for dwarf galaxies show a well-defined trend with the absolute magnitude of dwarf galaxies.