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1151. CCD UBVRI photometry of 7 open star clusters
ID:
ivo://CDS.VizieR/J/MNRAS/327/23
Title:
CCD UBVRI photometry of 7 open star clusters
Short Name:
J/MNRAS/327/23
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive cluster parameters and mass functions from new UBVRI CCD photometric observations of ~3500 stars reaching down to V~20mag for the distant southern open star clusters NGC 3105, NGC 3603, Melotte 105, Hogg 15, NGC 4815, Pismis 20 and NGC 6253. For NGC 3105 and Hogg 15, CCD data are presented for the first time. The observations were carried out in 1992 between February 28 and March 8, June 5 and 9, and July 9 and 12 in the Cousins U, B, V, R and I photometric bands using CCD detector at the 1.0-m Elizabeth Telescope at the South African Astronomical Observatory (SAAO), Sutherland.
1152. CCD VIc Photometry of M30 Stars
ID:
ivo://CDS.VizieR/J/ApJ/518/262
Title:
CCD VIc Photometry of M30 Stars
Short Name:
J/ApJ/518/262
Date:
21 Oct 2021
Publisher:
CDS
Description:
The file contains VIc data of the globular cluster M30. All frames were taken using a 2048x2048 pixel CCD with pixels covering 0.44 arcseconds on a side, for a total field of approximately 15 arcminutes on a side. Data were taken on 1994 July 78 at the Cerro Tololo Inter-American Observatory (CTIO) 4m telescope. The data were calibrated against Landolt (1983, Cat. <II/118>) standard stars.
1153. CCD Vilnius photometry of M56
ID:
ivo://CDS.VizieR/J/A+A/388/149
Title:
CCD Vilnius photometry of M56
Short Name:
J/A+A/388/149
Date:
21 Oct 2021
Publisher:
CDS
Description:
CCD observations of field stars in an area north-east of the globular cluster M 56 were obtained in six bands of the Vilnius photometric system. The data sets cover a field of 9'x9.5'. An outline of the data pathway from observations to reduction via IRAF is outlined in this text. Photometry of 366 stars brighter than 18th V magnitude has been obtained and the analysis of the observational errors is discussed.
1154. CCD Washington CT1T2 photometry of stars in LMC
ID:
ivo://CDS.VizieR/J/AJ/144/100
Title:
CCD Washington CT1T2 photometry of stars in LMC
Short Name:
J/AJ/144/100
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present photometry for an unprecedented database of some 5.5million stars distributed throughout the Large Magellanic Cloud main body, from 21 fields covering a total area of 7.6deg^2^, obtained from Washington CT_1_T_2_ CTIO 4m MOSAIC data. Extensive artificial star tests over the whole mosaic image data set and the observed behavior of the photometric errors with magnitude demonstrate the accuracy of the morphology and clearly delineate the position of the main features in the color-magnitude diagrams (CMDs). The representative T_1_(MS TO) mags are on average ~0.5mag brighter than the T_1_ mags for the 100% completeness level of the respective field, allowing us to derive an accurate age estimate. We have analyzed the CMD Hess diagrams and used the peaks in star counts at the main sequence turnoff and red clump (RC) locations to age date the most dominant sub-population (or "representative" population) in the stellar population mix. The metallicity of this representative population is estimated from the locus of the most populous red giant branch track. We use these results to derive age and metallicity estimates for all of our fields. The analyzed fields span age and metallicity ranges covering most of the galaxy's lifetime and chemical enrichment, i.e., ages and metallicities between ~1 and 13Gyr and ~-0.2 and -1.2dex, respectively. We show that the dispersions associated with the mean ages and metallicities represent in general a satisfactory estimate of the age/metallicity spread (~1-3 Gyr/0.2-0.3 dex), although a few subfields have a slightly larger age/metallicity spread. Finally, we revisit the study of the vertical structure (VS) phenomenon, a striking feature composed of stars that extend from the bottom, bluest end of the RC to ~0.45mag fainter. We confirm that the VS phenomenon is not clearly seen in most of the studied fields and suggest that its occurrence is linked to some other condition(s) in addition to the appropriate age, metallicity, and the necessary red giant star density.
1155. CCD Washington photometry of Antlia cluster
ID:
ivo://CDS.VizieR/J/MNRAS/497/1791
Title:
CCD Washington photometry of Antlia cluster
Short Name:
J/MNRAS/497/1791
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an extension of our previous research on the early-type galaxy population of the Antlia cluster (d~35Mpc), achieving a total coverage of ~2.6deg^2^ and performing surface photometry for ~300 galaxies, 130 of which are new uncatalogued ones. Such new galaxies mainly fall in the low surface brightness (LSB) regime, but there are also some lenticulars (S0) which support the existence of unique functions that connect bright and dwarf galaxies in the scaling relations. We analyse the projected spatial distribution of galaxies up to a distance of ~800kpc from NGC 3268, the adopted centre, as well as the radial velocity distribution and the correlation between galaxy colour and effective radius with the projected spatial distribution. We also obtain the luminosity function of the early-type galaxies and the distribution of stellar masses using the T1-band magnitudes and adopted mass-luminosity ratios. Additionally, we correlate the central galaxy distribution with an X-ray emission map from the literature. Based on the analysis of the radial velocities and galaxy colour distributions, we find that galaxies redder than the colour-magnitude relation (CMR) have a velocity distribution strongly concentrated towards the values of the dominant galaxies and are homogeneously distributed throughout the cluster. Those bluer than the CMR, in turn, have a much more extended radial velocity distribution and are concentrated towards the centre of the cluster. We also identify 12 candidates to ultra diffuse galaxies (UDG), that seem to be split into two families, and speculate about their origins in the context of the cluster structure.
1156. Ccompact group galaxies UV and IR SFR
ID:
ivo://CDS.VizieR/J/MNRAS/459/2948
Title:
Ccompact group galaxies UV and IR SFR
Short Name:
J/MNRAS/459/2948
Date:
21 Oct 2021
Publisher:
CDS
Description:
Compact groups of galaxies provide insight into the role of low-mass, dense environments in galaxy evolution because the low velocity dispersions and close proximity of galaxy members result in frequent interactions that take place over extended time-scales. We expand the census of star formation in compact group galaxies by Tzanavaris et al. (2010, Cat. J/ApJS/212/9) and collaborators with Swift UVOT, Spitzer IRAC and MIPS 24{mu}m photometry of a sample of 183 galaxies in 46 compact groups. After correcting luminosities for the contribution from old stellar populations, we estimate the dust-unobscured star formation rate (SFR_UV_) using the UVOT uvw2 photometry. Similarly, we use the MIPS 24 {mu}m photometry to estimate the component of the SFR that is obscured by dust (SFR_IR_). We find that galaxies which are MIR-active (MIR-'red'), also have bluer UV colours, higher specific SFRs, and tend to lie in HI-rich groups, while galaxies that are MIR-inactive (MIR-'blue') have redder UV colours, lower specific SFRs, and tend to lie in HI-poor groups. We find the SFRs to be continuously distributed with a peak at about 1M_{sun}_/yr, indicating this might be the most common value in compact groups. In contrast, the specific SFR distribution is bimodal, and there is a clear distinction between star-forming and quiescent galaxies. Overall, our results suggest that the specific SFR is the best tracer of gas depletion and galaxy evolution in compact groups.
1157. C-COSMOS Legacy sources multiwavelength catalog
ID:
ivo://CDS.VizieR/J/ApJ/817/34
Title:
C-COSMOS Legacy sources multiwavelength catalog
Short Name:
J/ApJ/817/34
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the catalog of optical and infrared counterparts of the Chandra COSMOS-Legacy Survey, a 4.6Ms Chandra program on the 2.2deg^2^ of the COSMOS field, combination of 56 new overlapping observations obtained in Cycle 14 with the previous C-COSMOS survey. In this Paper we report the i, K, and 3.6{mu}m identifications of the 2273 X-ray point sources detected in the new Cycle 14 observations. We use the likelihood ratio technique to derive the association of optical/infrared (IR) counterparts for 97% of the X-ray sources. We also update the information for the 1743 sources detected in C-COSMOS, using new K and 3.6{mu}m information not available when the C-COSMOS analysis was performed. The final catalog contains 4016 X-ray sources, 97% of which have an optical/IR counterpart and a photometric redshift, while ~54% of the sources have a spectroscopic redshift. The full catalog, including spectroscopic and photometric redshifts and optical and X-ray properties described here in detail, is available online. We study several X-ray to optical (X/O) properties: with our large statistics we put better constraints on the X/O flux ratio locus, finding a shift toward faint optical magnitudes in both soft and hard X-ray band. We confirm the existence of a correlation between X/O and the the 2-10keV luminosity for Type 2 sources. We extend to low luminosities the analysis of the correlation between the fraction of obscured AGNs and the hard band luminosity, finding a different behavior between the optically and X-ray classified obscured fraction.
1158. CDD V photometry of B2 radio galaxies
ID:
ivo://CDS.VizieR/J/A+AS/142/353
Title:
CDD V photometry of B2 radio galaxies
Short Name:
J/A+AS/142/353
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results of V-band CCD photometry for 72 low-luminosity radio galaxies from the B2 sample is presented. Most of these galaxies are of early type and their photometric and morphological properties are studied in the paper. We present the resulting surface brightness profiles and isophote parameters' profiles, including ellipticity, position angle, and B4, for 59 galaxies.
1159. CDFS survey: 2 Ms source catalogs
ID:
ivo://CDS.VizieR/J/ApJS/179/19
Title:
CDFS survey: 2 Ms source catalogs
Short Name:
J/ApJS/179/19
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present point-source catalogs for the ~2Ms exposure of the Chandra Deep Field-South (CDF-S) this is one of the two most sensitive X-ray surveys ever performed. The survey covers an area of ~436arcmin^2^ and reaches on-axis sensitivity limits of ~1.9x10^-17^ and ~1.3x10^-16^ergs/cm^2^/s for the 0.5-2.0 and 2-8keV bands, respectively. Four hundred and sixty-two X-ray point sources are detected in at least one of three X-ray bands that were searched; 135 of these sources are new compared to the previous ~1Ms CDF-S detections. Source positions are determined using centroid and matched-filter techniques; the median positional uncertainty is ~0.36". The X-ray-to-optical flux ratios of the newly detected sources indicate a variety of source types; ~55% of them appear to be active galactic nuclei, while ~45% appear to be starburst and normal galaxies. In addition to the main Chandra catalog, we provide a supplementary catalog of 86 X-ray sources in the ~2Ms CDF-S footprint that was created by merging the ~250ks Extended Chandra Deep Field-South with the CDF-S this approach provides additional sensitivity in the outer portions of the CDF-S. A second supplementary catalog that contains 30 X-ray sources was constructed by matching lower significance X-ray sources to bright optical counterparts (R<23.8) the majority of these sources appear to be starburst and normal galaxies. The total number of sources in the main and supplementary catalogs is 578. Optical R-band counterparts and basic optical and infrared photometry are provided for the X-ray sources in the main and supplementary catalogs. We also include existing spectroscopic redshifts for 224 of the X-ray sources.
1160. CDIPS. I. LCs from TESS sectors 6 and 7
ID:
ivo://CDS.VizieR/J/ApJS/245/13
Title:
CDIPS. I. LCs from TESS sectors 6 and 7
Short Name:
J/ApJS/245/13
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Transiting Exoplanet Survey Satellite (TESS) is providing precise time-series photometry for most star clusters in the solar neighborhood. Using the TESS images, we have begun a Cluster Difference Imaging Photometric Survey, in which we are focusing both on stars that are candidate cluster members and on stars that show indications of youth. Our aims are to discover giant transiting planets with known ages, and to provide light curves suitable for studies in stellar astrophysics. For this work, we made 159343 light curves of candidate young stars, across 596 distinct clusters. Each light curve represents between 20 and 25 days of observations of a star brighter than G_Rp_=16, with 30-minute sampling. We describe the image-subtraction and time-series analysis techniques we used to create the light curves, which have noise properties that agree with theoretical expectations. We also comment on the possible utility of the light-curve sample for studies of stellar rotation evolution and binary eccentricity damping.