- 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.
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- 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.
- 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.
- 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.
- 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.
- 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.
- ID:
- ivo://CDS.VizieR/II/286
- Title:
- VIRMOS deep imaging survey. VVDS-F02 catalog
- Short Name:
- II/286
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Franco-Italian VIRMOS project has delivered the VIMOS spectrograph for the European Southern Observatory Very Large Telescope (ESO-VLT). VIMOS is a VIsible imaging Multi-Object Spectrograph with outstanding multiplex capabilities: with 10 arcsec slits, spectra can be taken of 600 objects simultaneously. In integral field mode, a 6400-fibre Integral Field Unit (IFU) provides spectroscopy for all objects covering a 54x54arcsec^2^ area.
- ID:
- ivo://CDS.VizieR/J/ApJ/704/842
- Title:
- VIRUS-P spectroscopy of NGC 5194
- Short Name:
- J/ApJ/704/842
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the relation between the star formation rate (SFR) surface density ({Sigma}_SFR_) and the mass surface density of gas ({Sigma}_gas_) in NGC 5194 (a.k.a. M51a, Whirlpool Galaxy). Visible Integral field Replicable Unit Spectrograph Prototype (VIRUS-P) integral field spectroscopy of the central 4.1x4.1kpc^2^ of the galaxy is used to measure H{alpha}, H{beta}, [OIII]5007, [NII]6548,6584, and [SII]6717,6731 emission line fluxes for 735 regions ~170pc in diameter. We use the Balmer decrement to calculate nebular dust extinctions, and correct the observed fluxes in order to accurately measure {Sigma}_SFR_ in each region. Archival HI 21cm and CO maps with spatial resolution similar to that of VIRUS-P are used to measure the atomic and molecular gas surface density for each region.
16989. VIS3COS. III. Galaxy spectra
- ID:
- ivo://CDS.VizieR/J/A+A/633/A70
- Title:
- VIS3COS. III. Galaxy spectra
- Short Name:
- J/A+A/633/A70
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectroscopic observations of 466 galaxies in and around a superstructure at z~0.84 targeted by the VIMOS Spectroscopic Survey of a Supercluster in the COSMOS eld (VIS3COS). We use [OII]3727, H{delta}, and Dn4000 to trace recent, medium-, and long-term star formation histories and investigate the eect of stellar mass and local environment on them. By studying trends in individual and composite galaxy spectra, we find that stellar mass and environment play a role in the observed galactic properties. Galaxies with low stellar mass (10<log10(M*/M_{sun}_)<10.5) in the eld show the strongest H{delta} absorption. Similarly, the massive population (log10(M*/M_{sun}_) > 11) shows an increase in H absorption strengths in intermediate-density environments (e.g. filaments). Galaxies with intermediate stellar mass (10.5<log10(M*/M_{sun}_)<11) have similar H{delta} absorption proles in all environments, but show an indication of enhanced [OII] emission in intermediate-density environments. This indicates that field galaxies with low stellar mass and lament galaxies with high stellar mass are more likely to have experienced a recent burst of star formation, while galaxies of the intermediate stellar-mass show an increase of star formation at lament-like densities. We also find that the median [OII] equivalent width (|EW[OII]|) decreases from 27+/-2{AA} to 2.0^+0,5^_-0.4_{AA} and Dn4000 increases from 1.09+/-0.01 to 1.56+/-0.03 with increasing stellar mass (from ~10^9.25^ to ~10^11.35^M_{sun}_). For the dependence on the environment, we find that at fixed stellar mass, |EW[OII]| is tentatively lower in environments with higher density. We find for Dn4000 that the increase with stellar mass is sharper in denser environments, which indicates that these environments may accelerate galaxy evolution. Moreover, we find higher Dn4000 values in denser environments at fixed stellar mass, suggesting that galaxies are on average older and/or more metal rich in these dense environments. This set of tracers depicts a scenario where the most massive galaxies have, on average, the lowest specic star formation rates and the oldest stellar populations (age>~1Gyr, showing a mass-downsizing eect). We also hypothesize that the observed increase in star formation (higher EW[OII], higher specic star formation rate) at intermediate densities may lead to quenching because we find that the quenched fraction increases sharply from the lament to cluster-like regions at similar stellar masses.
- ID:
- ivo://CDS.VizieR/J/ApJ/858/111
- Title:
- Visible obs. of GOT C+ Northern sightlines
- Short Name:
- J/ApJ/858/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using visible, radio, microwave, and submillimeter data, we study several lines of sight toward stars generally closer than 1kpc on a component-by-component basis. We derive the component structure seen in absorption at visible wavelengths from CaII, CaI, KI, CH, CH+, and CN and compare it to emission from HI, CO and its isotopologues, and C+ from the GOT C+ (Galactic Observations of Terahertz C+) survey (Langer+ 2010A&A...521L..17L). The correspondence between components in emission and absorption helps create a more unified picture of diffuse atomic and molecular gas in the interstellar medium. We also discuss how these tracers are related to the CO-dark H2 gas probed by C+ emission and discuss the kinematic connections among the species observed.