Showing papers by "Massimo Capaccioli published in 2020"
European Southern Observatory1, Astronomical Observatory of Capodimonte2, National Academy of Sciences of Ukraine3, University of Kharkiv4, Swinburne University of Technology5, INAF6, University of Padua7, Pontifical Catholic University of Chile8, Kapteyn Astronomical Institute9, ASTRON10, University of Naples Federico II11
TL;DR: In this article, the photometric properties of the IC 1459 group were investigated based on the multi-band VST Early-type GAlaxy Survey (VEGAS) with the VLT Survey Telescope (VST).
Abstract: Context. This paper is based on the multi-band VST Early-type GAlaxy Survey (VEGAS) with the VLT Survey Telescope (VST). We present new deep photometry of the IC 1459 group in g and r band.Aims. The main goal of this work is to investigate the photometric properties of the IC 1459 group, and to compare our results with those obtained for other galaxy groups studied in VEGAS, in order to provide an initial view of the variation of their properties as a function of the evolution of the system.Methods. For all galaxies in the IC 1459 group, we fit isophotes and extract the azimuthally averaged surface-brightness profiles, the position angle, and ellipticity profiles as a function of the semi-major axis. We also extract the average colour profile. In each band, we estimate the total magnitude, effective radius, mean colour, and total stellar mass for each galaxy in the group. We then look at the structure of the brightest galaxies and the faint features in their outskirts, considering also the intragroup component.Results. The wide field of view, long integration time, high angular resolution, and arcsec-level seeing of OmegaCAM at VST allow us to map the light distribution of IC 1459 down to a surface brightness level of 29.26 mag arcsec−2 in g band and 28.85 mag arcsec−2 in r band, and out to 7−10R e , and to detect the optical counterpart of HI gas around IC 1459. We also carry out an in-depth exploration of three low-density environments and provide information to understand how galaxy and group properties change with the group evolution stage.Conclusions. Good agreement is found between our results and predictions of numerical simulations regarding the structural properties of the brightest galaxies of the groups. We suggest that the structure of the outer envelope of he brightest cluster galaxies (i.e. the signatures of past mergers and tidal interactions), the intra-group light, and the HI amount and distribution may be used as indicators of the evolutionary stage and mass assembly of galaxy groups.
29 citations
TL;DR: In this paper, the authors report the discovery of 27 low-surface brightness galaxies, of which 12 are candidates for ultra-diffuse galaxies (UDG) in the Hydra I cluster, based on deep observations taken as part of the VST Early-type Galaxy Survey (VEGAS).
Abstract: In this paper, we report the discovery of 27 low-surface brightness galaxies, of which 12 are candidates for ultra-diffuse galaxies (UDG) in the Hydra I cluster, based on deep observations taken as part of the VST Early-type Galaxy Survey (VEGAS). This first sample of UDG candidates in the Hydra I cluster represents an important step in our project that aims to enlarge the number of confirmed UDGs and, through study of statistically relevant samples, constrain the nature and formation of UDGs. This study presents the main properties of this class of galaxies in the Hydra I cluster. For all UDGs, we analysed the light and colour distribution, and we provide a census of the globular cluster (GC) systems around them. Given the limitations of a reliable GC selection based on two relatively close optical bands only, we find that half of the UDG candidates have a total GC population consistent with zero. Of the other half, two galaxies have a total population larger than zero at 2σ level. We estimate the stellar mass, the total number of GCs, and the GC specific frequency (S N ). Most of the candidates span a range of stellar masses of 107 − 108 M ⊙ . Based on the GC population of these newly discovered UDGs, we conclude that most of these galaxies have a standard or low dark matter content, with a halo mass of ≤1010 M ⊙ .
21 citations
INAF1
TL;DR: In this paper, the authors presented the catalogs of compact stellar systems in the Fornax cluster as well as extended background sources and point-like sources and derived ugri photometry of ~1.7 million sources over the $\sim$21 sq. degree area of FDS centered on NGC1399.
Abstract: This paper continues the series of the Fornax Deep Survey (FDS). Following the previous studies dedicated to extended Fornax cluster members, we present the catalogs of compact stellar systems in the Fornax cluster as well as extended background sources and point-like sources. We derive ugri photometry of ~1.7 million sources over the $\sim$21 sq. degree area of FDS centered on NGC1399. For a wider area, of $\sim$27 sq. degs extending in the direction of NGC1316, we provide gri data for ~3.1 million sources. To improve the morphological characterization of sources we generate multi-band image stacks by coadding the best seeing gri-band single exposures with a cut at FWHM<=0.9 arcsec. We use the multi-band stacks as detection frames. The identification of compact sources is obtained from a combination of photometric and morphometric selection criteria taking as reference the properties of sources with well-defined classification from the literature. We present a preliminary analysis of globular cluster (GC) distributions in the Fornax area. The study confirms and extends further previous results. We observe the inter-galactic population of GCs, a population of mainly blue GCs centered on NGC1399, extends over $\sim$0.9Mpc, with an ellipticity $\sim$0.65. Several sub-structures extend over $\sim$0.5Mpc along various directions. Two of these structures do not cross any bright galaxy; one of them appears to be connected to NGC1404, a bright galaxy close to the cluster core and particularly poor of GCs. Using the gri catalogs we analyze the GC distribution over the extended FDS area, and do not find any obvious GC sub-structure bridging the two brightest cluster galaxies, NGC1316 and NGC1399. Although NGC1316 is twice brighter of NGC1399 in optical bands we estimate a factor of 3-4 richer GC population around NGC1399 compared to NGC1316, out to galactocentric distances of 40 arcmin
18 citations
University of Sydney1, University of Groningen2, University of Naples Federico II3, University of Queensland4, Spanish National Research Council5, University of La Laguna6, European Southern Observatory7, Astronomical Observatory of Capodimonte8, Macquarie University9, University of Vienna10, University of Oulu11
TL;DR: In this article, the authors present deep integral field observations of a sample of 31 low-mass (10(7.5) < M-* < 10(9.5), M-circle dot) early-type galaxies in the Fornax cluster with the SAMI instrument.
Abstract: Dwarf ellipticals are the most common galaxy type in cluster environments; however, the challenges associated with their observation mean that their formation mechanisms are still poorly understood. To address this, we present deep integral field observations of a sample of 31 low-mass (10(7.5) < M-* < 10(9.5) M-circle dot) early-type galaxies in the Fornax cluster with the SAMI instrument. For 21 galaxies, our observations are sufficiently deep to construct spatially resolved maps of the stellar velocity and velocity dispersion - for the remaining galaxies, we extract global velocities and dispersions from aperture spectra only. From the kinematic maps, we measure the specific stellar angular momentum lambda(R) of the lowest mass dE galaxies to date. Combining our observations with early-type galaxy data from the literature spanning a large range in stellar mass, we find that lambda(R) decreases towards lower stellar mass, with a corresponding increase in the proportion of slowly rotating galaxies in this regime. The decrease of lambda(R) with mass in our sample dE galaxies is consistent with a similar trend seen in somewhat more massive spiral galaxies from the CALIFA survey. This suggests that the degree of dynamical heating required to produce dEs from low-mass starforming progenitors may be relatively modest and consistent with a broad range of formation mechanisms.
15 citations
TL;DR: Venhola et al. as discussed by the authors have published a list of the authors of the paper "Aku Venhola and Eija Laurikainen: Anonymity and Privatization: A.
Abstract: Aku Venhola1,2, Reynier Peletier2, Eija Laurikainen1, Heikki Salo1, Enrichetta Iodice3, Steffen Mieske4, Michael Hilker5, Carolin Wittmann6, Maurizio Paolillo7,3, Michele Cantiello8, Joachim Janz1,13, Marilena Spavone3, Raffaele D’Abrusco9, Glenn van de Ven14, Nicola Napolitano3, Gijs Verdoes Kleijn2, Massimo Capaccioli10, Aniello Grado3, Edwin Valentijn2, Jesús Falcón-Barroso11,12, and Luca Limatola3
13 citations
TL;DR: In this article, the authors presented the catalogs of compact stellar systems in the Fornax cluster, as well as extended background sources and point-like sources and derived ugri photometry of ∼1.7 million sources over the ∼21 square degree area of FDS centered on the bright central galaxy NGC 1399.
Abstract: Context. A possible pathway for understanding the events and the mechanisms involved in galaxy formation and evolution is an in-depth investigation of the galactic and inter-galactic fossil sub-structures with long dynamical timescales: stars in the field and in stellar clusters. Aims: This paper continues the Fornax Deep Survey (FDS) series. Following previous studies dedicated to extended Fornax cluster members, we present the catalogs of compact stellar systems in the Fornax cluster, as well as extended background sources and point-like sources. Methods: We derived ugri photometry of ∼1.7 million sources over the ∼21 square degree area of FDS centered on the bright central galaxy NGC 1399. For a wider area, of ∼27 square degrees extending in the direction of NGC 1316, we provided gri photometry for ∼3.1 million sources. To improve the morphological characterization of sources, we generated multi-band image stacks by coadding the best-seeing gri-band single exposures with a cut at full width at half maximum (FWHM) ≤ 0.″9. We used the multi-band stacks as master detection frames, with a FWHM improved by ∼15% and a FWHM variability from field to field reduced by a factor of ∼2.5 compared to the pass-band with the best FWHM, namely the r-band. The identification of compact sources, in particular, globular clusters (GC), was obtained from a combination of photometric (e.g., colors, magnitudes) and morphometric (e.g., concentration index, elongation, effective radius) selection criteria, also taking as reference the properties of sources with well-defined classifications from spectroscopic or high-resolution imaging data. Results: Using the FDS catalogs, we present a preliminary analysis of GC distributions in the Fornax area. The study confirms and extends further previous results that were limited to a smaller survey area. We observed the inter-galactic population of GCs, a population of mainly blue GCs centered on NGC 1399, extending over ∼0.9 Mpc, with an ellipticity ɛ ∼ 0.65 and a small tilt in the direction of NGC 1336. Several sub-structures extend over ∼0.5 Mpc along various directions. Two of these structures do not cross any bright galaxy; one of them appears to be connected to NGC 1404, a bright galaxy close to the cluster core and particularly poor in GCs. Using the gri catalogs, we analyze the GC distribution over the extended FDS area and do not find any obvious GC sub-structure bridging the two brightest cluster galaxies, namely, NGC 1316 and NGC 1399. Although NGC 1316 is more than twice as bright of NGC 1399 in optical bands, using gri data, we estimate a GC population that is richer by a factor of ∼3-4 around NGC 1399, as compared to NGC 1316, out to galactocentric distances of ∼40' or ∼230 kpc. Full Tables 3-6 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/639/A136
10 citations
Posted Content•
TL;DR: Venhola et al. as mentioned in this paper presented the first data release of the Fornax Deep Survey (FDS), animaging survey using using the wide-field imager OmegaCAM mounted on the VST in the SDSS u', g', r', and i'-bands.
Abstract: We present the first data release of the Fornax Deep Survey (FDS), animaging survey using using the wide-field imager OmegaCAM mounted on theVST in the SDSS u', g', r', and i'-bands covering the Fornax GalaxyCluster and the infalling Fornax A Group. FDS is a joint project betweenNOVA (previously called FOCUS - PI: R. F. Peletier) and INAF (as part ofVEGAS - PIs: M. Capaccioli and E. Iodice). With exposure times of about9 hours over an area of ~28 square degrees, this survey is a legacydataset for studies of members of the Fornax Galaxy Cluster and theinfalling Fornax A Group down to a surface brightness limit of ~28mag/arcsec^2 (1-sigma surface brightness over a 1 arcsecond^2 area) andopens a new parameter regime to investigate the role of the clusterenvironment in shaping the properties of its galaxy population. Afterthe Virgo cluster,Fornax is the second nearest galaxy cluster to us, andwith its different mass and evolutionary state, it provides a valuablecomparison that makes it possible to understand the various evolutionaryeffects on galaxies and galaxy clusters. Details about the survey can befound in A. Venhola, R. F. Peletier, E. Laurikainen et al., 2018,A&A 620, 165. In this release, 181 Gb of (compressed) fits filesreduced using the system are present. Catalogues with the completesample of sources including dwarf galaxies part of the cluster, globularclusters, and background galaxies will be provided in forthcomingreleases. The data products are available via the ESO Science Portal athttps://archive.eso.org/scienceportal/home?publ_date=2020-08-26
2 citations
TL;DR: In this paper, a new method, referred to as differential running-average photometry, is proposed to measure the light curves of the detected objects and perform detailed uncertainty analysis and detrending corrections on the light curve.
Abstract: The VST Optical Imaging of the CDFS and ES1 Fields (VOICE) Survey, in synergy with the SUDARE survey, is a deep optical $ugri$ imaging of the CDFS and ES1 fields using the VLT Survey Telescope (VST). The observations for the CDFS field comprise about 4.38 deg$^2$ down to $r\sim26$ mag. The total on-sky time spans over four years in this field, distributed over four adjacent sub-fields. In this paper, we use the multi-epoch $r$-band imaging data to measure the variability of the detected objects and search for transients. We perform careful astrometric and photometric calibrations and point spread function (PSF) modeling. A new method, referring to as differential running-average photometry, is proposed to measure the light curves of the detected objects. With the method, the difference of PSFs between different epochs can be reduced, and the background fluctuations are also suppressed. Detailed uncertainty analysis and detrending corrections on the light curves are performed. We visually inspect the light curves to select variable objects, and present some objects with interesting light curves. Further investigation of these objects in combination with multi-band data will be presented in our forthcoming paper.
1 citations