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A Search For" Dwarf" Seyfert Nuclei. VII. a Catalog of Central Stellar
TO APPEAR IN The Astrophysical Journal Supplement Series. Preprint typeset using LATEX style emulateapj v. 26/01/00 A SEARCH FOR “DWARF” SEYFERT NUCLEI. VII. A CATALOG OF CENTRAL STELLAR VELOCITY DISPERSIONS OF NEARBY GALAXIES LUIS C. HO The Observatories of the Carnegie Institution of Washington, 813 Santa Barbara St., Pasadena, CA 91101 JENNY E. GREENE1 Department of Astrophysical Sciences, Princeton University, Princeton, NJ ALEXEI V. FILIPPENKO Department of Astronomy, University of California, Berkeley, CA 94720-3411 AND WALLACE L. W. SARGENT Palomar Observatory, California Institute of Technology, MS 105-24, Pasadena, CA 91125 To appear in The Astrophysical Journal Supplement Series. ABSTRACT We present new central stellar velocity dispersion measurements for 428 galaxies in the Palomar spectroscopic survey of bright, northern galaxies. Of these, 142 have no previously published measurements, most being rela- −1 tively late-type systems with low velocity dispersions (∼<100kms ). We provide updates to a number of literature dispersions with large uncertainties. Our measurements are based on a direct pixel-fitting technique that can ac- commodate composite stellar populations by calculating an optimal linear combination of input stellar templates. The original Palomar survey data were taken under conditions that are not ideally suited for deriving stellar veloc- ity dispersions for galaxies with a wide range of Hubble types. We describe an effective strategy to circumvent this complication and demonstrate that we can still obtain reliable velocity dispersions for this sample of well-studied nearby galaxies. Subject headings: galaxies: active — galaxies: kinematics and dynamics — galaxies: nuclei — galaxies: Seyfert — galaxies: starburst — surveys 1. INTRODUCTION tors, apertures, observing strategies, and analysis techniques. -
1985Apjs ... 59 ...IW the Astrophysical Journal Supplement Series, 59:1-21,1985 September © 1985. the American Astronomical S
IW The Astrophysical Journal Supplement Series, 59:1-21,1985 September .... © 1985. The American Astronomical Society. All rights reserved. Printed in U.S.A. 59 ... A CATALOG OF STELLAR VELOCITY DISPERSIONS. I. 1985ApJS COMPILATION AND STANDARD GALAXIES Bradley C. Whitmore Space Telescope Science Institute Douglas B. McElroy Computer Sciences Corporation1 AND John L. Tonry California Institute of Technology Received 1984 October 23; accepted 1985 February 19 ABSTRACT A catalog of central stellar velocity dispersion measurements is presented, current through 1984 June. The catalog includes 1096 measurements of 725 galaxies. A set of 51 standard galaxies is defined which consists of galaxies with at least three reliable, concordant measurements. We suggest that future studies observe some of these standard galaxies in the course of their observations so that different studies can be normalized to the same system. We compare previous studies with the derived standards to determine relative accuracies and to compute scale factors where necessary. Subject headings: galaxies: internal motions I. INTRODUCTION be flattened by rotation. Results from Whitmore, Rubin, and The ability to make accurate measurements of stellar veloc- Ford (1984) conflict with the Kormendy and Illingworth con- ity dispersions has provided a major catalyst for the study of clusion. galactic structure and dynamics. Several important discoveries While most dispersion profiles are either flat or falling, have resulted from the use of this new tool. For example, a studies of cD galaxies at the center of rich clusters of galaxies correlation between the luminosity of an elliptical galaxy and have shown rising dispersion profiles (Dressier 1979; Carter the central stellar velocity dispersion was discovered by Faber et al 1981). -
Making a Sky Atlas
Appendix A Making a Sky Atlas Although a number of very advanced sky atlases are now available in print, none is likely to be ideal for any given task. Published atlases will probably have too few or too many guide stars, too few or too many deep-sky objects plotted in them, wrong- size charts, etc. I found that with MegaStar I could design and make, specifically for my survey, a “just right” personalized atlas. My atlas consists of 108 charts, each about twenty square degrees in size, with guide stars down to magnitude 8.9. I used only the northernmost 78 charts, since I observed the sky only down to –35°. On the charts I plotted only the objects I wanted to observe. In addition I made enlargements of small, overcrowded areas (“quad charts”) as well as separate large-scale charts for the Virgo Galaxy Cluster, the latter with guide stars down to magnitude 11.4. I put the charts in plastic sheet protectors in a three-ring binder, taking them out and plac- ing them on my telescope mount’s clipboard as needed. To find an object I would use the 35 mm finder (except in the Virgo Cluster, where I used the 60 mm as the finder) to point the ensemble of telescopes at the indicated spot among the guide stars. If the object was not seen in the 35 mm, as it usually was not, I would then look in the larger telescopes. If the object was not immediately visible even in the primary telescope – a not uncommon occur- rence due to inexact initial pointing – I would then scan around for it. -
Ngc Catalogue Ngc Catalogue
NGC CATALOGUE NGC CATALOGUE 1 NGC CATALOGUE Object # Common Name Type Constellation Magnitude RA Dec NGC 1 - Galaxy Pegasus 12.9 00:07:16 27:42:32 NGC 2 - Galaxy Pegasus 14.2 00:07:17 27:40:43 NGC 3 - Galaxy Pisces 13.3 00:07:17 08:18:05 NGC 4 - Galaxy Pisces 15.8 00:07:24 08:22:26 NGC 5 - Galaxy Andromeda 13.3 00:07:49 35:21:46 NGC 6 NGC 20 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 7 - Galaxy Sculptor 13.9 00:08:21 -29:54:59 NGC 8 - Double Star Pegasus - 00:08:45 23:50:19 NGC 9 - Galaxy Pegasus 13.5 00:08:54 23:49:04 NGC 10 - Galaxy Sculptor 12.5 00:08:34 -33:51:28 NGC 11 - Galaxy Andromeda 13.7 00:08:42 37:26:53 NGC 12 - Galaxy Pisces 13.1 00:08:45 04:36:44 NGC 13 - Galaxy Andromeda 13.2 00:08:48 33:25:59 NGC 14 - Galaxy Pegasus 12.1 00:08:46 15:48:57 NGC 15 - Galaxy Pegasus 13.8 00:09:02 21:37:30 NGC 16 - Galaxy Pegasus 12.0 00:09:04 27:43:48 NGC 17 NGC 34 Galaxy Cetus 14.4 00:11:07 -12:06:28 NGC 18 - Double Star Pegasus - 00:09:23 27:43:56 NGC 19 - Galaxy Andromeda 13.3 00:10:41 32:58:58 NGC 20 See NGC 6 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 21 NGC 29 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 22 - Galaxy Pegasus 13.6 00:09:48 27:49:58 NGC 23 - Galaxy Pegasus 12.0 00:09:53 25:55:26 NGC 24 - Galaxy Sculptor 11.6 00:09:56 -24:57:52 NGC 25 - Galaxy Phoenix 13.0 00:09:59 -57:01:13 NGC 26 - Galaxy Pegasus 12.9 00:10:26 25:49:56 NGC 27 - Galaxy Andromeda 13.5 00:10:33 28:59:49 NGC 28 - Galaxy Phoenix 13.8 00:10:25 -56:59:20 NGC 29 See NGC 21 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 30 - Double Star Pegasus - 00:10:51 21:58:39 -
NGVS). XVIII. Measurement and Calibration of Surface Brightness Fluctuation Distances for Bright Galaxies in Virgo (And Beyond
Publication Year 2018 Acceptance in OA@INAF 2020-11-02T17:16:45Z Title The Next Generation Virgo Cluster Survey (NGVS). XVIII. Measurement and Calibration of Surface Brightness Fluctuation Distances for Bright Galaxies in Virgo (and Beyond) Authors CANTIELLO, Michele; Blakeslee, John P.; Ferrarese, Laura; Côté, Patrick; Roediger, Joel C.; et al. DOI 10.3847/1538-4357/aab043 Handle http://hdl.handle.net/20.500.12386/28125 Journal THE ASTROPHYSICAL JOURNAL Number 856 The Astrophysical Journal, 856:126 (18pp), 2018 April 1 https://doi.org/10.3847/1538-4357/aab043 © 2018. The American Astronomical Society. All rights reserved. The Next Generation Virgo Cluster Survey (NGVS). XVIII. Measurement and Calibration of Surface Brightness Fluctuation Distances for Bright Galaxies in Virgo (and Beyond) Michele Cantiello1 , John P. Blakeslee2 , Laura Ferrarese2,3 , Patrick Côté2, Joel C. Roediger2 , Gabriella Raimondo1, Eric W. Peng4,5 , Stephen Gwyn2, Patrick R. Durrell6 , and Jean-Charles Cuillandre7 1 INAF Osservatorio Astronomico d’Abruzzo, via Maggini, snc, I-64100, Italy; [email protected] 2 National Research Council of Canada, Herzberg Astronomy and Astrophysics Research Centre, Victoria, BC, Canada 3 Gemini Observatory, Northern Operations Center, 670 N.A’ohoku Place, Hilo, HI 96720, USA 4 Department of Astronomy, Peking University, Beijing 100871, People’s Republic of China 5 Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, People’s Republic of China 6 Department of Physics and Astronomy, Youngstown -
Nuclear Stellar Discs in Low-Luminosity Elliptical Galaxies
Mon. Not. R. Astron. Soc. 000, 000–000 (0000) Printed 22 February 2018 (MN LATEX style file v2.2) Nuclear stellar discs in low-luminosity elliptical galaxies: NGC 4458 and NGC 4478 L. Morelli1,2, C. Halliday3, E. M. Corsini1, A. Pizzella1, D. Thomas4, R. P. Saglia4, R. L. Davies5, R. Bender4,6, M. Birkinshaw7, and F. Bertola1 1 Dipartimento di Astronomia, Universit`adi Padova, vicolo dell’Osservatorio 2, I-35122 Padova, Italy. 2 European Southern Observatory, 3107 Alonso de Cordova, Santiago, Chile. 3 INAF-Osservatorio Astronomico di Padova, vicolo dell’Osservatorio 5, I-35122 Padova, Italy. 4 Max-Planck Institut f¨ur extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching, Germany. 5 Department of Astrophysics, University of Oxford, Keble Road, Oxford, OX1 3RH. 6 Universit¨as-Sternwarte, Scheinerstrasse 1, D-81679 Muenchen, Germany. 7 H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK. Received 2004 May 20; accepted 2004 July 21 ABSTRACT We present the detection of nuclear stellar discs in the low-luminosity elliptical galaxies NGC 4458 and NGC 4478, which are known to host a kinematically-decoupledcore. Using archival HST imaging, and available absorption line-strength index data based on ground-based spec- troscopy, we investigate the photometric parameters and the properties of the stellar popula- tions of these central structures. Their scale length, h, and face-on central surface brightness, c c µ0, fit on µ0–h relation for galaxy discs. For NGC 4458 these parameters are typical for nu- clear discs, while the same quantities for NGC 4478 lie between those of nuclear discs and the discs of discy ellipticals. -
The ACS Virgo Cluster Survey. VI. Isophotal Analysis and Surface Brightness Profiles 3 at Odds with Previous Claims in Lauer Et Al
Rochester Institute of Technology RIT Scholar Works Articles 2006 The CA S Virgo Cluster Survey. VI. Isophotal Analysis and the Structure of Early-Type Galaxies Laura Ferrarese National Research Council of Canada Patrick Côté National Research Council of Canada Andrés Jordán European Southern Observatory Eric W. Peng National Research Council of Canada John P. Blakeslee The Johns Hopkins University See next page for additional authors Follow this and additional works at: http://scholarworks.rit.edu/article Recommended Citation Laura Ferrarese et al 2006 ApJS 164 334 https://doi.org/10.1086/501350 This Article is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Articles by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. Authors Laura Ferrarese, Patrick Côté, Andrés Jordán, Eric W. Peng, John P. Blakeslee, Slawomir Piatek, Simona Mei, David Merritt, Miloš Milosavljević, John L. Tonry, and Michael J. West This article is available at RIT Scholar Works: http://scholarworks.rit.edu/article/1182 Accepted by The Astrophysical Journal Supplements Preprint typeset using LATEX style emulateapj v. 10/10/03 THE ACS VIRGO CLUSTER SURVEY. VI. ISOPHOTAL ANALYSIS AND THE STRUCTURE OF EARLY-TYPE GALAXIES1 Laura Ferrarese2, Patrick Cotˆ e´2, Andres´ Jordan´ 3,4, Eric W. Peng2, John P. Blakeslee5,6, Slawomir Piatek7, Simona Mei5, David Merritt8, Miloˇs Milosavljevic´9,10, John L. Tonry11, & Michael J. West12 Accepted by The Astrophysical Journal Supplements ABSTRACT We present a detailed analysis of the morphology, isophotal parameters and surface brightness profiles for 100 early-type members of the Virgo Cluster, from dwarfs (MB = −15.1 mag) to giants (MB = −21.8 mag). -
Line-Of-Sight Velocity Distributions of Low-Luminosity Elliptical Galaxies
Mon. Not. R. Astron. Soc. 326, 473–489 (2001) Line-of-sight velocity distributions of low-luminosity elliptical galaxies C. Halliday,1P† Roger L. Davies,1 Harald Kuntschner,1 M. Birkinshaw,2 Ralf Bender,3 R. P. Saglia3 and Glenn Baggley1 1Department of Physics, University of Durham, Science Labs, South Road, Durham DH1 3LE 2H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL 3Universita¨ts-Sternwarte, Scheinerstr. 1, D-81679 Mu¨nchen, Germany Accepted 2001 March 7. Received 2000 December 21; in original form 2000 December 21 ABSTRACT The shape of the line-of-sight velocity distribution (LOSVD) is measured for a sample of 14 elliptical galaxies, predominantly low-luminosity ellipticals. The sample is dominated by galaxies in the Virgo cluster but also contains ellipticals in nearby groups and low-density environments. The parametrization of the LOSVD given by Gerhard and van der Marel & Franx is adopted, which measures the asymmetrical and symmetrical deviations of the LOSVD from a Gaussian by the amplitudes h3 and h4 of the Gauss–Hermite series. Rotation, velocity dispersion, h3 and h4 are determined as a function of radius for both major and minor axes. Non-Gaussian LOSVDs are found for all galaxies along the major axes. Deviations from a Gaussian LOSVD along the minor axis are of much lower amplitude if present at all. Central decreases in velocity dispersion are found for three galaxies. Two galaxies have kinematically decoupled cores: NGC 4458 and the well-known case of NGC 3608. Key words: galaxies: elliptical and lenticular, cD – galaxies: formation – galaxies: kinematics and dynamics. -
A Catalogue of 1180 Galaxies in the Direction of the Virgo Cluster's Core
ASTRONOMY & ASTROPHYSICS FEBRUARY I 1998, PAGE 367 SUPPLEMENT SERIES Astron. Astrophys. Suppl. Ser. 127, 367-395 (1998) The “Virgo photometry catalogue”; a catalogue of 1180 galaxies in the direction of the Virgo Cluster’s core C.K. Young1,2 and M.J. Currie3 1Beijing Astronomical Observatory, Chinese Academy of Sciences, Beijing 100080, China 2Department of Physics, University of Oxford, Nuclear and Astrophysics Laboratory, Keble Road, Oxford OX1 3RH, UK 3Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, UK Received February 25; accepted May 22, 1997 Abstract. We present a new catalogue of galaxies in merged images; our segmentation software being able to the direction of the Virgo Cluster’s core: the Virgo cope with the vast majority of image mergers. Photometry Catalogue (VPC)1. This catalogue contains 1180 galaxies (including background objects) within a 23 Key words: galaxies: clusters: individual: Virgo — square-degree area of the sky centred on R.A.1950.0 = catalogues — galaxies: fundamental parameters — h m ◦ 0 12 26 and dec.1950.0 =13 08 . The VPC galaxy sample galaxies: photometry comprises of non-stellar objects brighter than BJ25 =19.0; the completeness limits being BJ25 ≈ 18.5 for the northern half of the survey area and BJ25 ≈ 18.0 for the southern half. Independently-calibrated photographic surface pho- 1. Introduction tometry is presented for over 1000 galaxies in the U, BJ The Virgo Cluster, being the dominant nearby clus- and RC bands. Parameters listed for catalogued galax- ter of galaxies, has long attracted much attention. ies include: equatorial coordinates, morphological types, It is irregular and exhibits significant substructure. -
19 90MNRAS.2 42P. .24C Mon. Not. R. Astr. Soc. (1990) 242
Mon. Not. R. astr. Soc. (1990) 242, Short Communication, 24p-27p .24C 42P. Further evidence of continuity between elliptical and disc galaxies* 90MNRAS.2 19 Massimo Capaccioli Osservatorio Astronómico, Vicolo Osservatorio 5,1-35122 Padova, Italy Nicola Caon Dipartimento di Astronomía, Università di Padova, Vicolo Osservatorio 5,1-35122, Italy Roberto Rampazzo Osservatorio Astronómico di Brera, Via Brera 28,1-20121 Milano, Italy Accepted 1989 October 23. Received 1989 October 20; in original form 1989 July 28 SUMMARY The behaviour of the isophotes of the E galaxies in a new photometric sample of 33 early-type galaxies belonging to the Virgo cluster (Caon) is compared to that of the SO galaxies. Almost all objects flatter than b/a - 0.3 are found to exhibit ‘pointed’ (or ‘lemon-shaped’) isophotes irrespective of their Hubble class, while almost none do if rounder than the same limit. This observation is used to support the incipient scenario (Bender et al.) in which a large fraction ( - 1/2) of E galaxies - the so-called ‘disky ellipticals’ - populates one end of a disc-to-bulge sequence including SO and spiral galaxies. 1 INTRODUCTION 1987,1989a,b; Capaccioli etal. 1989; Carter 1987). Indirect About 15 years ago the first rotation curves for E galaxies evidence that a significant fraction of E galaxies may share (Bertola & Capaccioli 1975; Illingworth 1977) broke down the same structural properties of SO bulges has been already the classical picture in which all galaxies (and galaxy com- contained in Michard’s (1985) observation of the similarity ponents) were seen as rotationally supported oblate between the ellipticity profiles of flat Es and edge-on lenticu- spheroids. -
Elliptical Galaxies
Elliptical Galaxies Virgo Cluster: distance 15Mpc Elliptical Galaxies Elliptical galaxies are thought to be the simplest of all types of galaxies. Yet, detailed analysis shows that they are much more complicated that “dead spherish lumps”. Elliptical galaxies are typically found in clusters and groups of galaxies. Still, 10% of all field galaxies are ellipticals; 20% are S0’s and the rest is spirals. Elliptical galaxies dominate the bright end the very dim ends of the luminosity function. Examples: M49 and M87: Virgo Cluster Surface brightness profiles ! laws and approximations history: old good results more recent results: cores, cusps, power-laws and so on Projected Brightness Profiles of E Galaxies Are Sérsic (1968) Functions Sérsic (1968) generalization: 1/4 de Vaucouleurs (1948) r law: ! ! ! ! n = 1 ⇒ exponential (many disks) n = 4 ⇒ de Vaucouleurs law Laws and approximations de Vaucouleurs e where Ie is the surface brightness at Re Re is half-light radius Hubble law Cuspy profiles NFW Hernquist Nuker (for surface) Kravtsov (3D) Burkert (not cuspy) Deviations from ellipticity Examples of boxy and disky isophotes NGC821 NGC2300 Old results Concentration: log of ratio of outer radius to core radius. E’s have very large concentrations Old results indicated that the surface brightness profiles flatten close to the center (cores). This is now believed to be an effect of insufficient angular resolution. Note that profiles have different shapes: outer slopes are different for different galaxies. cD galaxies have very extended profiles Central galaxies in rich galaxy clusters extend to very large radii. They may account for a large fraction of the total cluster luminosity. -
The ACS Virgo Cluster Survey. VI. Isophotal Analysis and the Structure
Accepted by The Astrophysical Journal Supplements Preprint typeset using LATEX style emulateapj v. 10/10/03 THE ACS VIRGO CLUSTER SURVEY. VI. ISOPHOTAL ANALYSIS AND THE STRUCTURE OF EARLY-TYPE GALAXIES1 Laura Ferrarese2, Patrick Cotˆ e´2, Andres´ Jordan´ 3,4, Eric W. Peng2, John P. Blakeslee5,6, Slawomir Piatek7, Simona Mei5, David Merritt8, Miloˇs Milosavljevic´9,10, John L. Tonry11, & Michael J. West12 Accepted by The Astrophysical Journal Supplements ABSTRACT We present a detailed analysis of the morphology, isophotal parameters and surface brightness profiles for 100 early-type members of the Virgo Cluster, from dwarfs (MB = −15.1 mag) to giants (MB = −21.8 mag). Each galaxy has been imaged in two filters, closely resembling the Sloan g and z passbands, using the Advanced Camera for Surveys on board the Hubble Space Telescope. Dust and complex morphological structures are common. Dust is detected in as many as 18, prefer- entially bright, galaxies. The incidence rate in the 26 galaxies brighter than BT = 12.15 mag, which form a magnitude limited sample, is 42%. The amount and distribution of dust show no obvious cor- relations with galaxy morphology; dust features range from faint wisps and patches on tens of parsec scales, to regular, highly organized kpc-scale dust disks. Blue star clusters are interspersed within the larger, clumpier dust disks, while thin, dynamically cold stellar disks are seen in association with the smaller, uniform nuclear dust disks. Kiloparsec-scale stellar disks, bars, and nuclear stellar disks are seen in 60% of galaxies with interme- diate luminosity (−20 . MB . −17). In at least one case (VCC 1938 = NGC 4638), the large-scale stellar disk has a sharp inner edge, possibly produced when disk instabilities led to the formation of a (now dissolved) bar.