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3871. 2MASS6x survey of the Lockman Hole
ID:
ivo://CDS.VizieR/J/AJ/125/2521
Title:
2MASS6x survey of the Lockman Hole
Short Name:
J/AJ/125/2521
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have carried out a survey of the Lockman Hole covering over 24deg^2^ using the Two Micron All Sky Survey (2MASS) observing system in a special mode that reaches roughly 1mag deeper than the nominal 2MASS survey. The resultant point-source catalog reaches to approximately (J, H, Ks)<(17.8, 16.5, 16.0)mag with completeness and reliability in excess of 90%-95% at the faintest levels. These data will be useful in identifying sources in SIRTF surveys of this area. We have cataloged 69,115 objects, almost twice as many as in the nominal 2MASS survey of this region. The sample includes a large number of potential new active galaxies, as well as a T dwarf candidate.
3872. Master Catalogue towards the Magellanic Clouds (MC2)
ID:
ivo://CDS.VizieR/IV/33
Title:
Master Catalogue towards the Magellanic Clouds (MC2)
Short Name:
IV/33
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Master Catalogue of stars towards the Magellanic Clouds (MC2) is a multi-wavelength reference catalogue. The current paper presents the first results of the MC2 project. We started with a massive cross-identification of the two recently released near-infrared surveys: the DENIS Catalogue towards the Magellanic Clouds (DCMC) with more than 1.3 million sources identified in at least two of the three DENIS filters (I J Ks) and the 2nd Incremental Release of the 2MASS point source catalogue (J H Ks) covering the same region of the sky. Both point source catalogues provide an unprecedented wealth of data on the stellar populations of the Magellanic Clouds (MCs). The cross-matching procedure has been extended to optical wavelength ranges, including the UCAC1 (USNO) and GSC2.2 catalogues. New cross-matching procedures for very large catalogues have been developed and important results on the astrometric and photometric accuracy of the cross-identified catalogues were derived. The cross-matching of large surveys is an essential tool to improve our understanding of their specific contents. This study has been partly supported by the ASTROVIRTEL project that aims at improving access to astronomical archives as virtual telescopes. This work has been supported by ASTROVIRTEL, a project funded by the European Commission under FP5 Contract No. HPRI-CT-1999-00081.
3873. 2MASX/NVSS galaxies brighter than K_20fe_=12.25
ID:
ivo://CDS.VizieR/J/ApJ/872/148
Title:
2MASX/NVSS galaxies brighter than K_20fe_=12.25
Short Name:
J/ApJ/872/148
Date:
21 Oct 2021
Publisher:
CDS
Description:
We identified 15658 NRAO VLA Sky Survey (NVSS) radio sources among the 55288 2 Micron All-Sky Survey eXtended (2MASX) galaxies brighter than k_20fe_=12.25 at {lambda}=2.16{mu}m and covering the {Omega}=7.016sr of sky defined by J2000 {delta}>-40{deg} and |b|>20{deg}. The complete sample of 15043 galaxies with 1.4GHz flux densities S>=2.45mJy contains a 99.9% spectroscopically complete subsample of 9517 galaxies with k_20fe_<=11.75. We used only radio and infrared data to quantitatively distinguish radio sources powered primarily by recent star formation from those powered by active galactic nuclei. The radio sources with log[L(W/Hz)]>19.3 that we used to derive the local spectral luminosity and power-density functions account for >99% of the total 1.4GHz spectral power densities U_SF_=(1.54+/-0.20)x10^19^W/Hz/Mpc^3^ and U_AGN_=(4.23+/-0.78)x10^19^W/Hz/Mpc^3^ in the universe today, and the spectroscopic subsample is large enough that the quoted errors are dominated by cosmic variance. The recent comoving star formation rate density indicated by USF is {psi}~0.015M_{sun}_/yr/Mpc^3^.
3874. MATLAS dwarfs structure and morphology
ID:
ivo://CDS.VizieR/J/MNRAS/506/5494
Title:
MATLAS dwarfs structure and morphology
Short Name:
J/MNRAS/506/5494
Date:
22 Feb 2022
Publisher:
CDS
Description:
We present a photometric study of the dwarf galaxy population in the low to moderate density environments of the MATLAS (Mass Assembly of early-Type gaLAxies with their fine Structures) deep imaging survey. The sample consists of 2210 dwarfs, including 508 nucleated. We define a nucleus as a compact source that is close to the galaxy photocentre (within 0.5Re) which is also the brightest such source within the galaxy's effective radius. The morphological analysis is performed using a 2D surface brightness profile modelling on the g-band images of both the galaxies and nuclei. Our study reveals that, for similar luminosities, the MATLAS dwarfs show ranges in the distribution of structural properties comparable to cluster (Virgo and Fornax) dwarfs and a range of sizes comparable to the Local Group and Local Volume dwarfs. Colour measurements using the r- and i-band images indicate that the dwarfs in low and moderate density environments are as red as cluster dwarfs on average. The observed similarities between dwarf ellipticals in vastly different environments imply that dEs are not uniquely the product of morphological transformation due to ram-pressure stripping and galaxy harassment in high density environments. We measure that the dwarf nuclei are located predominantly in massive, bright and round dwarfs and observe fewer nuclei in dwarfs with a faint centre and a small size. The colour of the galaxy nucleus shows no clear relation to the colour of the dwarf, in agreement with the migration and wet migration nucleus formation scenarios. The catalogues of the MATLAS dwarfs photometric and structural properties are provided.
3875. MATLAS ultra diffuse galaxies
ID:
ivo://CDS.VizieR/J/A+A/654/A105
Title:
MATLAS ultra diffuse galaxies
Short Name:
J/A+A/654/A105
Date:
22 Feb 2022
Publisher:
CDS
Description:
Recent advances in deep dedicated imaging surveys over the past decade have uncovered a surprisingly large number of extremely faint low surface brightness galaxies with large physical sizes called ultra diffuse galaxies (UDGs) in clusters and, more recently, in lower density environments. As part of the Mass Assembly of early-Type GaLAxies with their fine Structures (MATLAS) survey, a deep imaging large program at the Canada-France-Hawaii Telescope (CFHT), our team has identified 2210 dwarf galaxies, 59 (~3%) of which qualify as UDGs. Averaging over the survey area, we find ~0.4 UDG per square degree. They are found in a range of low to moderate density environments, although 61% of the sample fall within the virial radii of groups. Based on a detailed analysis of their photometric and structural properties, we find that the MATLAS UDGs do not show significant differences from the traditional dwarfs, except from the predefined size and surface brightness cut. Their median color is as red as the one measured in galaxy clusters, albeit with a narrower color range. The majority of the UDGs are visually classified as dwarf ellipticals with log stellar masses of 6.5-8.7. The fraction of nucleated UDGs (~34%) is roughly the same as the nucleated fraction of the traditional dwarfs. Only five (~8%) UDGs show signs of tidal disruption and only two are tidal dwarf galaxy candidates. A study of globular cluster (GC) candidates selected in the CFHT images finds no evidence of a higher GC specific frequency S_N for UDGs than for classical dwarfs, contrary to what is found in most clusters. The UDG halo-to-stellar mass ratio distribution, as estimated from the GC counts, peaks at roughly the same value as for the traditional dwarfs, but spans the smaller range of ~10-2000. We interpret these results to mean that the large majority of the field-to-group UDGs do not have a different formation scenario than traditional dwarfs.
3876. MaxBCG catalog of 13823 galaxy clusters from SDSS
ID:
ivo://CDS.VizieR/J/ApJ/660/239
Title:
MaxBCG catalog of 13823 galaxy clusters from SDSS
Short Name:
J/ApJ/660/239
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of galaxy clusters selected using the maxBCG red-sequence method from Sloan Digital Sky Survey photometric data. This catalog includes 13823 clusters with velocity dispersions greater than ~400km/s and is the largest galaxy cluster catalog assembled to date. They are selected in an approximately volume-limited way from a 0.5Gpc^3^ region covering 7500deg^2^ of sky between redshifts 0.1 and 0.3. Each cluster contains between 10 and 190 E/S0 ridgeline galaxies brighter than 0.4L* within a scaled radius R_200_.
3877. M31B eclipsing binaries and Cepheids
ID:
ivo://CDS.VizieR/J/AJ/115/1016
Title:
M31B eclipsing binaries and Cepheids
Short Name:
J/AJ/115/1016
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have undertaken a long-term project, DIRECT, to obtain the direct distances to two important galaxies in the cosmological distance ladder - M31 and M33 - using detached eclipsing binaries (DEBs) and Cepheids. While rare and difficult to detect, DEBs provide us with the potential to determine these distances with an accuracy better than 5%. The extensive photometry obtained in order to detect DEBs provides us with good light curves for the Cepheid variables. These are essential to the parallel project to derive direct Baade-Wesselink distances to Cepheids in M31 and M33. For both Cepheids and eclipsing binaries, the distance estimates will be free of any intermediate steps. As a first step in the DIRECT project, between 1996 September and 1997 January we obtained 36 full nights on the Michigan-Dartmouth-MIT Observatory 1.3m telescope and 45 full/partial nights on the F.L. Whipple Observatory 1.2m telescope to search for DEBs and new Cepheids in the M31 and M33 galaxies. In this paper, first in a series, we present the catalog of variable stars, most of them newly detected, found in the field M31B [({alpha},{delta})=(11.20{deg}, 41.59{deg}), J2000.0]. We have found 85 variable stars: 12 eclipsing binaries, 38 Cepheids, and 35 other periodic, possible long-period or nonperiodic variables. The catalog of variables, as well as their photometry and finding charts, is available via anonymous ftp and the World Wide Web: http://cfa-www.harvard.edu/~kstanek/DIRECT.
3878. M 68 BVRI photometry
ID:
ivo://CDS.VizieR/J/AJ/99/1831
Title:
M 68 BVRI photometry
Short Name:
J/AJ/99/1831
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present BVRI photometry of the low metallicity globular cluster M68 (NGC 4590) observed with a CCD camera and the 2.2m telescope at ESO/La Silla, and have compared our BV color-magnitude diagrams with the observational results of a previous research. At magnitudes V<22, our BV results, obtained using the INVENTORY code, are in very close agreement with those of the other authors who used DAOPHOT in their reductions. At fainter levels, selection effects appear to affect INVENTORY more than DAOPHOT. We find that V_TO-HB_=3.42+/-0.10, in accord with values found for other clusters. The comparison between our four-color observations and the theoretical isochrones consistently yield a cluster age of 13Gyr with a likely external uncertainty of 2 or 3Gyr. Our derived values for the interstellar reddening at longer wavelengths are generally in agreement (+/-0.02mag) with what would be expected assuming E(B-V)=0.07mag and (m-M)_V_=15.25.
3879. M67 CCD photometry
ID:
ivo://CDS.VizieR/J/BaltA/7/369
Title:
M67 CCD photometry
Short Name:
J/BaltA/7/369
Date:
21 Oct 2021
Publisher:
CDS
Description:
Seven-color CCD photometry in the Vilnius photometric system of 279 stars down to V=15mag in the open cluster M 67 area is obtained. 13 standard stars in the cluster are measured photoelectrically. Photometric spectral types have been determined for all the stars. The reddening of the cluster is found to be E(B-V)=0.045, the true distance modulus is 9.38mag and the age is 4x10^9^ years. For a description of the Vilnius photometric system, see e.g. <GCPD/21>
3880. M 4 CCD photometry
ID:
ivo://CDS.VizieR/J/AJ/114/189
Title:
M 4 CCD photometry
Short Name:
J/AJ/114/189
Date:
21 Oct 2021
Publisher:
CDS
Description:
With the ESO NTT, we have obtained accurate CCD UBVI photometry of 1649 stars in an extended field in the globular cluster M 4 = NGC 6121. The position of the main-sequence turnoff is found to be at V_TO_=17.0+/-0.1mag, (B-V)=0.863+/-0.007, (V-I)=1.224+/-0.010, (B-I)=2.084+/-0.010. Our turnoff point is redder and fainter than those found for M 4 in the majority of recent studies, probably because of our field being located in the western, most reddened part of the cluster. The spread of stars around the main-sequence locus has an unusual shape (broadening near the turnoff point and close to the photometric limit), earlier noticed by Richer et al. (1995ApJ...451L..17R) and attributed by them to photometric effects. We have analyzed the possible reasons for this effect and concluded that, at least in our case, it is most probably due to differential absorption. We confirm the deviation of theoretical isochrones from the fainter parts of the M 4 main-sequence locus found by Alcaino et al. (1988ApJ...330..569A). Several curious structural details (a depression and an excess of stars) have been revealed in the brighter parts of the main-sequence luminosity function of M 4.