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24001. Virgo cluster ETGs: GC and galaxy diffuse light
ID:
ivo://CDS.VizieR/J/ApJ/806/133
Title:
Virgo cluster ETGs: GC and galaxy diffuse light
Short Name:
J/ApJ/806/133
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a kinematic analysis of the globular cluster (GC) systems and diffuse stellar light of four intermediate luminosity (sub-L*) early-type galaxies in the Virgo cluster based on Gemini Multi-Object Spectrographs (GMOS) data. Our galaxy sample is fainter (-23.8<M_K_<-22.7) than most previous studies, nearly doubling the number of galaxies in this magnitude range that now have GC kinematics. The data for the diffuse light extends to 4R_e_, and the data for the GCs reaches 8-12R_e_. We find that the kinematics in these outer regions are all different despite the fact that these four galaxies have similar photometric properties, and are uniformly classified as "fast rotators" from their stellar kinematics within 1R_e_. The GC systems exhibit a wide range of kinematic morphology. The rotation axis and amplitude can change between the inner and outer regions, including a case of counter-rotation. This difference shows the importance of wide-field kinematic studies, and shows that stellar and GC kinematics can change significantly as one moves beyond the inner regions of galaxies. Moreover, the kinematics of the GC systems can differ from that of the stars, suggesting that the formation of the two populations are also distinct.
24002. Virgo cluster radio luminosity function. I.
ID:
ivo://CDS.VizieR/J/A+A/343/86
Title:
Virgo cluster radio luminosity function. I.
Short Name:
J/A+A/343/86
Date:
21 Oct 2021
Publisher:
CDS
Description:
We cross-correlate the galaxies brighter than m_B_=18 in the Virgo cluster with the radio sources in the NVSS survey (1.4GHz), resulting in 180 radio-optical identifications. We determine the radio luminosity function of the Virgo galaxies, separately for the early- and late-types. Late-type galaxies develop radio sources with a probability proportional to their optical luminosity. In fact their radio/optical (R_B_) distribution is gaussian, centered at log R_B_~-0.5, i.e. the radio luminosity is ~0.3 of the optical one. The probability of late-type galaxies to develop radio sources is almost independent of their detailed Hubble type, except for Sa (and S0+S0a) which are a factor of ~5 less frequent than later types at any R_B_. Giant elliptical galaxies feed "monster" radio sources with a probability strongly increasing with mass. However the frequency of fainter radio sources is progressively less sensitive on the system mass. The faintest giant E galaxies (M_B_=-17) have a probability of feeding low power radio sources similar to that of dwarf E galaxies as faint as M_B_=-13.
24003. Virgo cluster ultraviolet sources
ID:
ivo://CDS.VizieR/J/ApJS/111/143
Title:
Virgo cluster ultraviolet sources
Short Name:
J/ApJS/111/143
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyze three UV images covering a ~100 square degree field toward the Virgo cluster, obtained by the FAUST space experiment. We detect 191 sources to a signal-to-noise ratio of 4.4 and identify 94% of them. Most sources have optical counterparts in existing catalogs, and about half are identified as galaxies. Some sources with no listed counterpart were observed at the Wise Observatory. We present the results of low-resolution visible spectrophotometry and discuss the foreground 101 stellar sources and the 76 detected galaxies, both in the cluster and in the foreground or background. We derive conclusions on star formation properties of galaxies and on the total UV flux from discrete and diffuse sources in the cluster. We test for the presence of intracluster dust, determine the clustering properties of UV emitting galaxies, and derive the UV luminosity function of Virgo galaxies.
24004. Virgo early-type galaxies optical properties
ID:
ivo://CDS.VizieR/J/A+A/538/A69
Title:
Virgo early-type galaxies optical properties
Short Name:
J/A+A/538/A69
Date:
21 Oct 2021
Publisher:
CDS
Description:
Studies of dwarf spheroidal (dSph) galaxies with statistically significant sample sizes are still rare beyond the Local Group, since these low surface brightness objects can only be identified with deep imaging data. In galaxy clusters, where they constitute the dominant population in terms of number, they represent the faint end slope of the galaxy luminosity function and provide important insight on the interplay between galaxy mass and environment. In this study we investigate the optical photometric properties of early-type galaxies (dwarf ellipticals (dEs) and dSphs) in the Virgo cluster core region, by analysing their location on the colour magnitude relation (CMR) and the structural scaling relations down to faint magnitudes, and by constructing the luminosity function to compare it with theoretical expectations.
24005. Virgo Filaments. I. CO and HI data
ID:
ivo://CDS.VizieR/J/A+A/657/A9
Title:
Virgo Filaments. I. CO and HI data
Short Name:
J/A+A/657/A9
Date:
21 Mar 2022 09:21:25
Publisher:
CDS
Description:
It is now well established that galaxies have different morphology, gas content and star formation rate in dense environments like galaxy clusters. The impact of environmental density extends to several virial radii, and galaxies appear to be pre-processed in filaments and groups, before falling into the cluster. Our goal is to quantify this pre-processing, in terms of gas content, and star formation rate, as a function of density in cosmic filaments. We have observed the two first CO transitions in 163 galaxies with the IRAM-30m telescope, and added 82 more measurements from the literature, for a sample of 245 galaxies in the filaments around Virgo cluster. We gathered HI-21cm measurements from the literature, and observed 69 galaxies with the Nancay telescope, to complete our sample. We compare our filament galaxies with comparable samples from the Virgo cluster and with the isolated galaxies of the AMIGA sample. We find a clear progression from field galaxies to filament and cluster ones for decreasing star formation rate, increasing fraction of galaxies in the quenching phase, increasing proportion of early-type galaxies and decreasing gas content. Galaxies in the quenching phase, defined as having star formation rate below one third of the main sequence rate, are only between 0-20% in the isolated sample, according to local galaxy density, while they are 20-60% in the filaments and 30-80% in the Virgo cluster. Processes that lead to star formation quenching are already at play in filaments. They depend mostly on the local galaxy density, while the distance to the filament spine is a secondary parameter. While the HI to stellar mass ratio decreases with local density by an order of magnitude in the filaments, and two orders of magnitude in the Virgo cluster with respect to the field, the decrease is much less for the H2 to stellar mass ratio. As the environmental density increases, the gas depletion time decreases, since the gas content decreases faster than the star formation rate. This suggests that gas depletion significantly precedes star formation quenching.
24006. Virgo & Fornax clusters galaxies UBVRI data
ID:
ivo://CDS.VizieR/J/A+AS/118/441
Title:
Virgo & Fornax clusters galaxies UBVRI data
Short Name:
J/A+AS/118/441
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present photoelectric multi-aperture photometry in UBVRI of 171 and 46 galaxies in the Virgo and Fornax clusters, respectively. Many of the galaxies have not been observed in at least one of these passbands before. We discuss the reduction and transformation into the Cousins photometric system as well as the extinction coefficients obtained between 1990 and 1993.
24007. Virgo intracluster planetary nebula candidates
ID:
ivo://CDS.VizieR/J/ApJS/145/65
Title:
Virgo intracluster planetary nebula candidates
Short Name:
J/ApJS/145/65
Date:
21 Oct 2021
Publisher:
CDS
Description:
Intracluster stars - stars outside of individual galaxies - are a sensitive measure of the poorly understood processes of galactic mergers, cluster accretion, and tidal stripping that occur in galaxy clusters. In particular, intracluster planetary nebulae are a useful probe of intracluster light as a whole. We present a catalog of 318 intracluster planetary nebula candidates in the nearby Virgo Cluster of galaxies, taken with the Kitt Peak National Observatory 4m telescope. We detail the automated detection routines developed to search for these candidates and discuss the routines' strengths and weaknesses. We discuss the importance of contamination in the catalog, and the likely causes. We present magnitudes and positions of these candidates, suitable for spectroscopic follow-up observations. Analyses of these candidates are presented in other papers of this series.
24008. Virgo Photometry Catalogue (VPC)
ID:
ivo://CDS.VizieR/J/A+AS/127/367
Title:
Virgo Photometry Catalogue (VPC)
Short Name:
J/A+AS/127/367
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Virgo Photometry Catalogue (VPC) contains independently calibrated surface photometry in the U, B_J_ and R_C_ bands for over 1000 galaxies (including background objects) brighter than B_J25_=19.0 in a 23{deg}^2^ area of the sky centred on R.A., Dec.(1950)= 12h26m, +13{deg}08'. The angular resolution of the photometry varies from band to band and was in each case determined from the FWHM of stellar profiles: 4.75+/-0.1arcsec in the U band, 5.0+/-0.1arcsec in the B_J_ band and 6.0+/-0.1arcsec in the R_C_ band. The photometry was intended for the derivation of accurate magnitudes and colours and is therefore not of high resolution. Stellar contamination of the galaxy sample is minimal, and cannot exceed about 3 faint-end objects in total (i.e. it is less than about 0.25%). Parameters listed for catalogued galaxies include: equatorial coordinates; morphological types; surface-brightness profile parameters (which preserve the majority of the surface photometry information); U, B_J_ and R_C_ isophotal magnitudes; U, B_J_, R_C_ and [transformed] B total magnitudes; (U-B_J_) and (B_J_-R_C_) equal-area colours, apparent angular radii, ellipticities, position angles, heliocentric radial velocities and alternative designations. All total magnitudes and total colours are extrapolated according to the "t" system of Young et al. (1998A&AS..130..173Y). The VPC is based primarily on four UK-Schmidt plates, all of which were scanned using the COSMOS measuring machine at the Royal Observatory Edinburgh. All magnitudes, colours and surface-brightness parameters are derived from numerical integrations of segmented plate-scan data; except for (in 109 cases) saturated and (in 51 cases) inextricably merged images. The latter 51 images are listed in Table 14 (Appendix D) of the original paper, whilst data for the remaining 1129 objects [i.e. including ones for which the VPC photometry is saturated in one or more bands] are listed in the main catalogue.
24009. Virial analysis of the dense cores in Orion A
ID:
ivo://CDS.VizieR/J/ApJ/846/144
Title:
Virial analysis of the dense cores in Orion A
Short Name:
J/ApJ/846/144
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use data on gas temperature and velocity dispersion from the Green Bank Ammonia Survey and core masses and sizes from the James Clerk Maxwell Telescope Gould Belt Survey to estimate the virial states of dense cores within the Orion A molecular cloud. Surprisingly, we find that almost none of the dense cores are sufficiently massive to be bound when considering only the balance between self-gravity and the thermal and non-thermal motions present in the dense gas. Including the additional pressure binding imposed by the weight of the ambient molecular cloud material and additional smaller pressure terms, however, suggests that most of the dense cores are pressure-confined.
24010. VIr light curves of GK Aqr
ID:
ivo://CDS.VizieR/J/other/NewA/38.50
Title:
VIr light curves of GK Aqr
Short Name:
J/other/NewA/38.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We made the first VRI CCD light curves of the short-period contact eclipsing binary GK Aqr, which was observed on October 5 and 8, 2013 at Xinglong station of National Astronomical Observatories, China. The ephemeris of GK Aqr was calculated based on our two newly obtained minima and the minima that other observers obtained previously. We discovered that the orbital period of GK Aqr exhibits an increasing trend of dP/dt=2.8(0.1)x10^-7^days/year by means of fitting the O-C values of the minima. This phenomenon might be explained by mass transfer from the primary (less massive) component to the secondary (more massive) one. With the updated Wilson & Devinney (1971ApJ...166..605W) program, we obtained the photometric orbital parameters for the first time. Using our parameters, we also successfully explained the light curve obtained from the All Sky Automated Survey data. In the end, we concluded that GK Aqr is a near contact binary with a low contact factor of 5.2%. As the mass transfer continues, GK Aqr could become a contact system and evolve into an over-contact system.

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