S. Zibetti

University of Virginia, Charlottesville, Virginia, United States

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Publications (115)342.72 Total impact

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    ABSTRACT: This paper characterizes the radial structure of stellar population properties of galaxies in the nearby universe, based on 300 galaxies from the CALIFA survey. The sample covers a wide range of Hubble types, and galaxy stellar mass. We apply the spectral synthesis techniques to recover the stellar mass surface density, stellar extinction, light and mass-weighted ages, and mass-weighted metallicity, for each spatial resolution element in our target galaxies. To study mean trends with overall galaxy properties, the individual radial profiles are stacked in seven bins of galaxy morphology. We confirm that more massive galaxies are more compact, older, more metal rich, and less reddened by dust. Additionally, we find that these trends are preserved spatially with the radial distance to the nucleus. Deviations from these relations appear correlated with Hubble type: earlier types are more compact, older, and more metal rich for a given mass, which evidences that quenching is related to morphology, but not driven by mass. Negative gradients of ages are consistent with an inside-out growth of galaxies, with the largest ages gradients in Sb-Sbc galaxies. Further, the mean stellar ages of disks and bulges are correlated, with disks covering a wider range of ages, and late type spirals hosting younger disks. The gradients in stellar mass surface density depend mostly on stellar mass, in the sense that more massive galaxies are more centrally concentrated. There is a secondary correlation in the sense that at the same mass early type galaxies have steeper gradients. We find mildly negative metallicity gradients, shallower than predicted from models of galaxy evolution in isolation. The largest gradients occur in Sb galaxies. Overall we conclude that quenching processes act in manners that are independent of mass, while metallicity and galaxy structure are influenced by mass-dependent processes.
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    ABSTRACT: We have obtained deep NIR narrow and broad (J and Y) band imaging data of the GOODS-South field. The narrow band filter is centered at 1060 nm corresponding to redshifts $z = 0.62, 1.15, 1.85$ for the strong emission lines H$\alpha$, $[$OIII$]$/H$\beta$ and $[$OII$]$, respectively. From those data we extract a well defined sample ($M(AB)=24.8$ in the narrow band) of objects with large emission line equivalent widths in the narrow band. Via SED fits to published broad band data we identify which of the three lines we have detected and assign redshifts accordingly. This results in a well defined, strong emission line selected sample of galaxies down to lower masses than can easily be obtained with only continuum flux limited selection techniques. We compare the (SED fitting-derived) main sequence of star-formation (MS) of our sample to previous works and find that it has a steeper slope than that of samples of more massive galaxies. We conclude that the MS steepens at lower (below $M_{\star} = 10^{9.4} M_{\odot}$) galaxy masses. We also show that the SFR at any redshift is higher in our sample. We attribute this to the targeted selection of galaxies with large emission line equivalent widths, and conclude that our sample presumably forms the upper boundary of the MS. We briefly investigate and outline how samples with accurate redshifts down to those low stellar masses open a new window to study the formation of large scale structure in the early universe. In particular we report on the detection of a young galaxy cluster at $z=1.85$ which features a central massive galaxy which is the candidate of an early stage cD galaxy, and we identify a likely filament mapped out by $[$OIII$]$ and $H\beta$ emitting galaxies at $z=1.15$.
    Astronomy and Astrophysics 04/2015; DOI:10.1051/0004-6361/201425535 · 4.48 Impact Factor
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    ABSTRACT: This White Paper presents the scientific motivations for a multi-object spectrograph (MOS) on the European Extremely Large Telescope (E-ELT). The MOS case draws on all fields of contemporary astronomy, from extra-solar planets, to the study of the halo of the Milky Way and its satellites, and from resolved stellar populations in nearby galaxies out to observations of the earliest 'first-light' structures in the partially-reionised Universe. The material presented here results from thorough discussions within the community over the past four years, building on the past competitive studies to agree a common strategy toward realising a MOS capability on the E-ELT. The cases have been distilled to a set of common requirements which will be used to define the MOSAIC instrument, entailing two observational modes ('high multiplex' and 'high definition'). When combined with the unprecedented sensitivity of the E-ELT, MOSAIC will be the world's leading MOS facility. In analysing the requirements we also identify a high-multiplex MOS for the longer-term plans for the E-ELT, with an even greater multiplex (>1000 targets) to enable studies of large-scale structures in the high-redshift Universe. Following the green light for the construction of the E-ELT the MOS community, structured through the MOSAIC consortium, is eager to realise a MOS on the E-ELT as soon as possible. We argue that several of the most compelling cases for ELT science, in highly competitive areas of modern astronomy, demand such a capability. For example, MOS observations in the early stages of E-ELT operations will be essential for follow-up of sources identified by the James Webb Space Telescope (JWST). In particular, multi-object adaptive optics and accurate sky subtraction with fibres have both recently been demonstrated on sky, making fast-track development of MOSAIC feasible.
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    ABSTRACT: We present three independent catalogs of point-sources extracted from SPIRE images at 250, 350, and 500 micron as a part of the Herschel Virgo Cluster Survey (HeViCS). The source positions are determined by estimating the likelihood to be a real source for each peak on the maps and the flux densities are estimated using the sourceExtractorTimeline, a timeline-based point source fitter. Afterwards, each source is subtracted from the maps, removing a Gaussian function in every position with the full width half maximum equal to that estimated in sourceExtractorTimeline. This procedure improves the robustness of our algorithm in terms of source identification. The HeViCS catalogs contain about 52000, 42200, and 18700 sources selected at 250, 350, and 500 micron above 3sigma and are ~ 75%, 62%, and 50% complete at flux densities of 20 mJy at 250, 350, 500 micron, respectively. We then measured source number counts at 250, 350, and 500 micron and we also cross-correlated the catalogs with the Sloan Digital Sky Survey to investigate the redshift distribution of the nearby sources. From this cross-correlation, we select ~2000 sources with reliable fluxes and a high signal-to-noise ratio, finding an average redshift z~0.3+/-0.22. The number counts at 250, 350, and 500 micron show an increase in the slope below 200 mJy, indicating a strong evolution in number of density for galaxies at these fluxes. In general, models tend to overpredict the counts at brighter flux densities, underlying the importance of studying the Rayleigh-Jeans part of the spectral energy distribution to refine the theoretical recipes of the models. Our iterative method for source identification allowed the detection of a family of 500 micron sources that are not foreground objects belonging to Virgo and not found in other catalogs.
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    ABSTRACT: We present the results of a new, ultra-deep, near-infrared imaging survey executed with the Hawk-I imager at the ESO VLT, of which we make all the data public. This survey, named HUGS (Hawk-I UDS and GOODS Survey), provides deep, high-quality imaging in the K and Y bands over the CANDELS UDS and GOODS-South fields. We describe here the survey strategy, the data reduction process, and the data quality. HUGS delivers the deepest and highest quality K-band images ever collected over areas of cosmological interest, and ideally complements the CANDELS data set in terms of image quality and depth. The seeing is exceptional and homogeneous, confined to the range 0.38"-0.43". In the deepest region of the GOODS-S field, (which includes most of the HUDF) the K-band exposure time exceeds 80 hours of integration, yielding a 1-sigma magnitude limit of ~28.0 mag/sqarcsec. In the UDS field the survey matches the shallower depth of the CANDELS images reaching a 1-sigma limit per sq.arcsec of ~27.3mag in the K band and ~28.3mag in the Y-band, We show that the HUGS observations are well matched to the depth of the CANDELS WFC3/IR data, since the majority of even the faintest galaxies detected in the CANDELS H-band images are also detected in HUGS. We present the K-band galaxy number counts produced by combining the HUGS data from the two fields. We show that the slope of the number counts depends sensitively on the assumed distribution of galaxy sizes, with potential impact on the estimated extra-galactic background light (abridged).
    Astronomy and Astrophysics 09/2014; 570. DOI:10.1051/0004-6361/201423543 · 4.48 Impact Factor
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    ABSTRACT: Physical conditions of the interstellar medium in galaxies are closely linked to the ambient radiation field and the heating of dust grains. In order to characterize dust properties in galaxies over a wide range of physical conditions, we present here the radial surface brightness profiles of the entire sample of 61 galaxies from Key Insights into Nearby Galaxies: Far-Infrared Survey with Herschel (KINGFISH). The main goal of our work is the characterization of the grain emissivities, dust temperatures, and interstellar radiation fields responsible for heating the dust. After fitting the dust and stellar radial profiles with exponential functions, we fit the far-infrared spectral energy distribution (SED) in each annular region with single-temperature modified black bodies using both variable (MBBV) and fixed (MBBF) emissivity indices beta, as well as with physically motivated dust models. Results show that while most SED parameters decrease with radius, the emissivity index beta also decreases with radius in some galaxies, but in others is increasing, or rising in the inner regions and falling in the outer ones. Despite the fixed grain emissivity (average beta~ 2.1) of the physically-motivated models, they are well able to accommodate flat spectral slopes with beta<= 1. We find that flatter slopes (beta<= 1.5) are associated with cooler temperatures, contrary to what would be expected from the usual Tdust-beta degeneracy. This trend is related to variations in Umin since beta and Umin are very closely linked over the entire range in Umin sampled by the KINGFISH galaxies: low Umin is associated with flat beta<=1. Both these results strongly suggest that the low apparent \beta values (flat slopes) in MBBV fits are caused by temperature mixing along the line-of-sight, rather than by intrinsic variations in grain properties. Abstract truncated for arXiv.
    Astronomy and Astrophysics 09/2014; 576. DOI:10.1051/0004-6361/201424734 · 4.48 Impact Factor
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    ABSTRACT: We present a detailed analysis of the influence of the environment and of the environmental history on quenching star formation in central and satellite galaxies in the local Universe. We take advantage of publicly available galaxy catalogues obtained from applying a galaxy formation model to the Millennium simulation. In addition to halo mass, we consider the local density of galaxies within various fixed scales. Comparing our model predictions to observational data [Sloan Digital Sky Survey (SDSS)], we demonstrate that the models are failing to reproduce the observed density dependence of the quiescent galaxy fraction in several aspects: for most of the stellar mass ranges and densities explored, models cannot reproduce the observed similar behaviour of centrals and satellites, they slightly underestimate the quiescent fraction of centrals and significantly overestimate that of satellites. We show that in the models, the density dependence of the quiescent central galaxies is caused by a fraction of ‘backsplash’ centrals which have been satellites in the past. The observed stronger density dependence on scales of 0.2–1 Mpc may, however, indicate additional environmental processes working on central galaxies. Turning to satellite galaxies, the density dependence of their quiescent fractions reflects a dependence on the time spent orbiting within a parent halo, correlating strongly with halo mass and distance from the halo centre. Comparisons with observational estimates suggest relatively long gas consumption time-scales of roughly 5 Gyr in low-mass satellite galaxies. The quenching time-scales decrease with increasing satellite stellar mass. Overall, a change in modelling both internal processes and environmental processes is required for improving currently used galaxy formation models.
    Monthly Notices of the Royal Astronomical Society 09/2014; 444(3):2938-2959. DOI:10.1093/mnras/stu1609 · 5.23 Impact Factor
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    ABSTRACT: We map the neutral atomic gas content of M33 using high resolution VLA and GBT observations and fit a tilted ring model to determine the orientation of the extended gaseous disk and its rotation curve. The disk of M33 warps from 8 kpc outwards without substantial change of its inclination with respect to the line of sight. Rotational velocities rise steeply with radius in the inner disk, reaching 100 km/s in 4 kpc, then the rotation curve becomes more perturbed and flatter with velocities as high as 120-130 km/s out to 23 kpc. We derive the stellar mass surface density map of M33's optical disk, via pixel -SED fitting methods based on population synthesis models, which highlights variations in the mass-to-light ratio. The stellar mass surface further out is estimated from deep images of outer disk fields. Stellar and gas maps are then used in the dynamical analysis of the rotation curve to constrain the dark matter distribution which is relevant at all radii. A dark matter halo with a Navarro-Frenk-White density profile in a LCDM cosmology, provides the best fit to the rotation curve for a dark halo concentration C=10 and a total halo mass of 4.3 10^{11}Msun. This imples a baryonic fraction of order 0.02 and the evolutionary history of this galaxy should account for loss of a large fraction of its original baryonic content.
    Astronomy and Astrophysics 09/2014; 572. DOI:10.1051/0004-6361/201424033 · 4.48 Impact Factor
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    ABSTRACT: We present a detailed analysis of the influence of the environment and of the environmental history on quenching star formation in central and satellite galaxies in the local Universe. We take advantage of publicly available galaxy catalogues obtained from applying a galaxy formation model to the Millennium simulation. In addition to halo mass, we consider the local density of galaxies within various fixed scales. Comparing our model predictions to observational data (SDSS), we demonstrate that the models are failing to reproduce the observed density dependence of the quiescent galaxy fraction in several aspects: for most of the stellar mass ranges and densities explored, models cannot reproduce the observed similar behaviour of centrals and satellites, they slightly under-estimate the quiescent fraction of centrals and significantly over-estimate that of satellites. We show that in the models, the density dependence of the quiescent central galaxies is caused by a fraction of "backsplash" centrals which have been satellites in the past (and were thus suffering from environmental processes). Turning to satellite galaxies, the density dependence of their quiescent fractions reflects a dependence on the time spent orbiting within a parent halo of a particular mass, correlating strongly with halo mass and distance from the halo centre. Comparisons with observational estimates suggest relatively long gas consumption time scales of roughly 5 Gyr in low mass satellite galaxies. The quenching time scales decrease with increasing satellite stellar mass. Overall, a change in modelling both internal processes (star formation and feedback) and environmental processes (e.g. making them dependent on dynamical friction time-scales and preventing the re-accretion of gas onto backsplash galaxies) is required for improving currently used galaxy formation models.
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    ABSTRACT: We describe and discuss the selection procedure and statistical properties of the galaxy sample used by the Calar Alto Legacy Integral Field Area Survey (CALIFA), a public legacy survey of 600 galaxies using integral field spectroscopy. The CALIFA "mother sample" was selected from the Sloan Digital Sky Survey (SDSS) DR7 photometric catalogue to include all galaxies with an r-band isophotal major axis between 45" and 79.2" and with a redshift 0.005 < z < 0.03. The mother sample contains 939 objects, 600 of which will be observed in the course of the CALIFA survey. The selection of targets for observations is based solely on visibility and thus keeps the statistical properties of the mother sample. By comparison with a large set of SDSS galaxies, we find that the CALIFA sample is representative of galaxies over a luminosity range of -19 > Mr > -23.1 and over a stellar mass range between 10^9.7 and 10^11.4Msun. In particular, within these ranges, the diameter selection does not lead to any significant bias against - or in favour of - intrinsically large or small galaxies. Only below luminosities of Mr = -19 (or stellar masses < 10^9.7Msun) is there a prevalence of galaxies with larger isophotal sizes, especially of nearly edge-on late-type galaxies, but such galaxies form < 10% of the full sample. We estimate volume-corrected distribution functions in luminosities and sizes and show that these are statistically fully compatible with estimates from the full SDSS when accounting for large-scale structure. We also present a number of value-added quantities determined for the galaxies in the CALIFA sample. We explore different ways of characterizing the environments of CALIFA galaxies, finding that the sample covers environmental conditions from the field to genuine clusters. We finally consider the expected incidence of active galactic nuclei among CALIFA galaxies.
    Astronomy and Astrophysics 07/2014; 569. DOI:10.1051/0004-6361/201424198 · 4.48 Impact Factor
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    ABSTRACT: While studies of gas-phase metallicity gradients in disc galaxies are common, very little has been done in the acquisition of stellar abundance gradients in the same regions. We present here a comparative study of the stellar metallicity and age distributions in a sample of 62 nearly face-on, spiral galaxies with and without bars, using data from the CALIFA survey. We measure the slopes of the gradients and study their relation with other properties of the galaxies. We find that the mean stellar age and metallicity gradients in the disc are shallow and negative. Furthermore, when normalized to the effective radius of the disc, the slope of the stellar population gradients does not correlate with the mass or with the morphological type of the galaxies. Contrary to this, the values of both age and metallicity at $\sim$2.5 scale-lengths correlate with the central velocity dispersion in a similar manner to the central values of the bulges, although bulges show, on average, older ages and higher metallicities than the discs. One of the goals of the present paper is to test the theoretical prediction that non-linear coupling between the bar and the spiral arms is an efficient mechanism for producing radial migrations across significant distances within discs. The process of radial migration should flatten the stellar metallicity gradient with time and, therefore, we would expect flatter stellar metallicity gradients in barred galaxies. However, we do not find any difference in the metallicity or age gradients in galaxies with without bars. We discuss possible scenarios that can lead to this absence of difference.
    Astronomy and Astrophysics 06/2014; 570. DOI:10.1051/0004-6361/201423635 · 4.48 Impact Factor
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    ABSTRACT: Over the past 18 months we have revisited the science requirements for a multi-object spectrograph (MOS) for the European Extremely Large Telescope (E-ELT). These efforts span the full range of E-ELT science and include input from a broad cross-section of astronomers across the ESO partner countries. In this contribution we summarise the key cases relating to studies of high-redshift galaxies, galaxy evolution, and stellar populations, with a more expansive presentation of a new case relating to detection of exoplanets in stellar clusters. A general requirement is the need for two observational modes to best exploit the large (>40 sq. arcmin) patrol field of the E-ELT. The first mode ('high multiplex') requires integrated-light (or coarsely resolved) optical/near-IR spectroscopy of >100 objects simultaneously. The second ('high definition'), enabled by wide-field adaptive optics, requires spatially-resolved, near-IR of >10 objects/sub-fields. Within the context of the conceptual study for an ELT-MOS called MOSAIC, we summarise the top-level requirements from each case and introduce the next steps in the design process.
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    ABSTRACT: The chemo-dynamics of galaxy halos beyond the Local Group may now be mapped out through the use of globular clusters and planetary nebulae as bright tracer objects, along with deep multi-slit spectroscopy of the integrated stellar light. We present results from surveying nearby early-type galaxies, including evidence for kinematically distinct halos that may reflect two-phase galaxy assembly. We also demonstrate the utility of the tracer approach in measuring the kinematics of stellar substructures around the Umbrella Galaxy, which allow us to reconstruct the progenitor properties and stream orbit.
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    ABSTRACT: The fraction of galaxies with red colours depends sensitively on environment, and on the way in which environment is measured. To distinguish competing theories for the quenching of star formation, a robust and complete description of environment is required, to be applied to a large sample of galaxies. The environment of galaxies can be described using the density field of neighbours on multiple scales - the multiscale density field. We are using the Millennium simulation and a simple HOD prescription which describes the multiscale density field of Sloan Digital Sky Survey DR7 galaxies to investigate the dependence of the fraction of red galaxies on the environment. Using a volume limited sample where we have sufficient galaxies in narrow density bins, we have more dynamic range in halo mass and density for satellite galaxies than for central galaxies. Therefore we model the red fraction of central galaxies as a constant while we use a functional form to describe the red fraction of satellites as a function of halo mass which allows us to distinguish a sharp from a gradual transition. While it is clear that the data can only be explained by a gradual transition, an analysis of the multiscale density field on different scales suggests that colour segregation within the haloes is needed to explain the results. We also rule out a sharp transition for central galaxies, within the halo mass range sampled.
    Monthly Notices of the Royal Astronomical Society 12/2013; 438(3). DOI:10.1093/mnras/stt2339 · 5.23 Impact Factor
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    ABSTRACT: We have identified a low surface brightness stellar stream from visual inspection of SDSS imaging for the edge-on, spiral galaxy NGC5387. A blue overdensity was also identified in SDSS coincident with the stream intersection with the NGC5387 disk. The overdensity was also detected in the GALEX Deep Imaging Survey and found to contribute 38% of the total FUV integrated flux from NGC5387, which suggests that the region is actively forming stars. Deeper imaging was acquired with the Vatican Advanced Technology Telescope (VATT) in the B, V, and R filters that confirmed the presence of both the stellar stream and the blue overdensity. Analysis of the VATT photometry indicates the stellar stream is red in color, B-V = 0.7, and has a stellar mass of 6x10^8 M$_{\odot}$, which implies a merger ratio of 1:50. Assessment of the stream morphology suggests that the merger event has a circular radius, R~16 kpc, the stream formed in ~400 Myr, and the progenitor had a total mass of ~2x10 M$_{\odot}$. Spectroscopy from LBT+MODS1 was used to determine that the blue overdensity is at the same redshift as NGC5387, consists of young stellar populations (~10 Myr), is metal-poor (12 + log(O/H) = 8.03), and forming stars at an enhanced rate (~1-3 M$_{\odot}$/year) given its total stellar mass (2x10^7 M$_{\odot}$). Several interpretations are posited to explain these observational data, of which the most likely are (i) that the blue overdensity is a region of enhanced star formation in the outer disk of NGC5387 induced by the minor accretion event, and (ii) that the blue overdensity is the progenitor of the stellar stream undergoing a period of enhanced star formation as a result of its interaction with NGC5387. Confirmation and theoretical exploration of these scenarios are presented in a companion paper.
    The Astrophysical Journal 12/2013; 790(2). DOI:10.1088/0004-637X/790/2/117 · 6.28 Impact Factor
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    ABSTRACT: Passive early-type galaxies (ETGs) provide an ideal laboratory for studying the interplay between dust formation around evolved stars and its subsequent destruction in a hot gas. Using Spitzer-IRS and Herschel data we compare the dust production rate in the envelopes of evolved AGB stars with a constraint on the total dust mass. Early-type galaxies which appear to be truly passively evolving are not detected by Herschel. We thus derive a distance independent upper limit to the dust grain survival time in the hostile environment of ETGs of <46 ± 25 Myr for amorphous silicate grains. This implies that ETGs which are detected at far-infrared wavelengths have acquired a cool dusty medium via interaction. Given likely time-scales for ram-pressure stripping, this also implies that only galaxies with dust in a cool (atomic) medium can release dust into the intra-cluster medium.
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    ABSTRACT: The origin of the far-infrared emission from the nearby radio galaxy M 87 remains a matter of debate. Some studies find evidence of a far-infrared excess due to thermal dust emission, whereas others propose that the far-infrared emission can be explained by synchrotron emission without the need for an additional dust emission component. We present Herschel PACS and SPIRE observations of M 87, taken as part of the science demonstration phase observations of the Herschel Virgo Cluster Survey. We compare these data with a synchrotron model based on mid-infrared, far-infrared, submm and radio data from the literature to investigate the origin of the far-infrared emission. Both the integrated SED and the Herschel surface brightness maps are adequately explained by synchrotron emission. At odds with previous claims, we find no evidence of a diffuse dust component in M 87, which is not unexpected in the harsh X-ray environment of this radio galaxy sitting at the core of the Virgo cluster.
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    ABSTRACT: We use high-resolution VLT/HAWK-I and HST/WFC3 imaging to study the structural evolution of early-type galaxies since z˜2. Mass-selected samples are drawn from pre-existing photometric redshift surveys, which are then separated into actively star-forming and passive galaxies. The (projected) axis-ratio distributions are compared with those of lower redshift samples, and we reconstruct intrinsic axis-ratio distributions by assuming that galaxies are simple, axi-symmetric systems. We find that at all redshifts z<˜2 more massive galaxies are rounder. That is, at all epochs stars are predominantly formed in disk-like systems, whereas early-type galaxies are more bulge dominated, especially at higher masses.
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    ABSTRACT: We use dust scaling relations to investigate the hypothesis that Virgo cluster transition-type dwarfs are infalling star-forming field galaxies, which is argued based on their optical features (e.g. disks, spiral arms, bars) and kinematic properties similar to late-type galaxies. After their infall, environmental effects gradually transform them into early-type galaxies through the removal of their interstellar medium and quenching of all star formation activity. In this paper, we aim to verify whether this hypothesis holds using far-infrared diagnostics based on Herschel observations of the Virgo cluster taken as part of the Herschel Virgo Cluster Survey (HeViCS). We select transition-type objects in the nearest cluster, Virgo, based on spectral diagnostics indicative for their residual or ongoing star formation. We detect dust Md ~ 10^{5-6} Msun in 36% of the transition-type dwarfs located on the high end of the stellar mass distribution. This suggests that the dust reservoirs present in non-detections fall just below the Herschel detection limit (< 1.1x10^5 Msun). Dust scaling relations support the hypothesis of a transformation between infalling late-type galaxies to quiescent low-mass spheroids governed by environmental effects, with dust-to-stellar mass fractions for transition-type dwarfs in between values characteristic for late-type objects and the lower dust fractions observed in early-type galaxies. Several transition-type dwarfs demonstrate blue central cores, hinting at the radially outside-in removal of gas and quenching of star formation activity. The fact that dust is also confined to the inner regions suggests that metals are stripped in the outer regions along with the gas. In the scenario of most dust being stripped from the galaxy along with the gas, we argue that... (abridged)
    Monthly Notices of the Royal Astronomical Society 08/2013; 436(2). DOI:10.1093/mnras/stt1626 · 5.23 Impact Factor
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    ABSTRACT: The Herschel Virgo Cluster Survey (HeViCS) is the deepest, confusion-limited survey of the Virgo Cluster at far-infrared (FIR) wavelengths. The entire survey at full depth covers ~55deg2 in five bands (100-500um), encompassing the areas around the central dominant elliptical galaxies (M87, M86 and M49) and extends as far as the NW cloud, the W cloud and the Southern extension. The survey extends beyond this region with lower sensitivity so that the total area covered is 84 deg2. In this paper we describe the data, the data acquisition techniques and present the detection rates of the optically selected Virgo Cluster Catalogue (VCC). We detect 254 (34%) of 750 VCC galaxies found within the survey boundary in at least one band and 171 galaxies are detected in all five bands. For the remainder of the galaxies we have measured strict upper limits for their FIR emission. (2 data files).

Publication Stats

4k Citations
342.72 Total Impact Points

Institutions

  • 2013
    • University of Virginia
      • Department of Astronomy
      Charlottesville, Virginia, United States
  • 2009–2013
    • IT University of Copenhagen
      København, Capital Region, Denmark
  • 2008–2013
    • Max Planck Institute for Astronomy
      Heidelburg, Baden-Württemberg, Germany
  • 2009–2011
    • Dark Cosmology Centre
      København, Capital Region, Denmark
  • 2005–2008
    • Max Planck Institute for Extraterrestrial Physics
      Arching, Bavaria, Germany
  • 2001–2004
    • Università degli Studi di Milano-Bicocca
      Milano, Lombardy, Italy
  • 2002
    • University of Toledo
      • Department of Physics and Astronomy
      Toledo, Ohio, United States