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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. -
Arxiv:Astro-Ph/9902377V1 26 Feb 1999 Sus Uha H Omcxrybcgon.Ide,Tedis the Indeed, Background
The distribution of absorbing column densities among Seyfert 2 galaxies G. Risaliti Dipartimento di Astronomia e Scienza dello Spazio, Univerit`adi Firenze, L. E. Fermi 5, I-50125, Firenze, Italy R. Maiolino and M. Salvati Osservatorio Astrofisico di Arcetri, L. E. Fermi 5, I-50125 Firenze, Italy ABSTRACT We use hard X-ray data for an “optimal” sample of Seyfert 2 galaxies to derive the distribution of the gaseous absorbing column densities among obscured active nuclei in the local Universe. Of all Seyfert 2 galaxies in the sample, 75% are heavily obscured 23 −2 24 −2 (NH > 10 cm ) and about half are Compton thick (NH > 10 cm ). Intermediate type 1.8–1.9 Seyferts are characterized by an average NH much lower than “strict” Seyfert 2s. No correlation is found between NH and the intrinsic luminosity of the nuclear source. This NH distribution has important consequences for the synthesis of the cosmic X-ray background. Also, the large fraction of Compton thick objects implies that most of the obscuring gas is located within a radius of a few 10 pc from the nucleus. Subject headings: Galaxies: active — Galaxies: nuclei — Galaxies: Seyfert — X-rays: galaxies arXiv:astro-ph/9902377v1 26 Feb 1999 1. Introduction According to the so-called unified model (Antonucci 1993) the same engine is at work in all Active Galactic Nuclei (AGNs). The differences between type 1 and type 2 AGNs are ascribed solely to orientation effects: our line of sight to the nucleus may (type 2) or may not (type 1) be obstructed by optically thick material, perhaps distributed in a toroidal geometry. -
Lopsided Spiral Galaxies: Evidence for Gas Accretion
A&A 438, 507–520 (2005) Astronomy DOI: 10.1051/0004-6361:20052631 & c ESO 2005 Astrophysics Lopsided spiral galaxies: evidence for gas accretion F. Bournaud1, F. Combes1,C.J.Jog2, and I. Puerari3 1 Observatoire de Paris, LERMA, 61 Av. de l’Observatoire, 75014 Paris, France e-mail: [email protected] 2 Department of Physics, Indian Institute of Science, Bangalore 560012, India 3 Instituto Nacional de Astrofísica, Optica y Electrónica, Calle Luis Enrique Erro 1, 72840 Tonantzintla, Puebla, Mexico Received 3 January 2005 / Accepted 15 March 2005 Abstract. We quantify the degree of lopsidedness for a sample of 149 galaxies observed in the near-infrared from the OSUBGS sample, and try to explain the physical origin of the observed disk lopsidedness. We confirm previous studies, but for a larger sample, that a large fraction of galaxies have significant lopsidedness in their stellar disks, measured as the Fourier amplitude of the m = 1 component normalised to the average or m = 0 component in the surface density. Late-type galaxies are found to be more lopsided, while the presence of m = 2 spiral arms and bars is correlated with disk lopsidedness. We also show that the m = 1 amplitude is uncorrelated with the presence of companions. Numerical simulations were carried out to study the generation of m = 1viadifferent processes: galaxy tidal encounters, galaxy mergers, and external gas accretion with subsequent star formation. These simulations show that galaxy interactions and mergers can trigger strong lopsidedness, but do not explain several independent statistical properties of observed galaxies. To explain all the observational results, it is required that a large fraction of lopsidedness results from cosmological accretion of gas on galactic disks, which can create strongly lopsided disks when this accretion is asymmetrical enough. -
SAC's 110 Best of the NGC
SAC's 110 Best of the NGC by Paul Dickson Version: 1.4 | March 26, 1997 Copyright °c 1996, by Paul Dickson. All rights reserved If you purchased this book from Paul Dickson directly, please ignore this form. I already have most of this information. Why Should You Register This Book? Please register your copy of this book. I have done two book, SAC's 110 Best of the NGC and the Messier Logbook. In the works for late 1997 is a four volume set for the Herschel 400. q I am a beginner and I bought this book to get start with deep-sky observing. q I am an intermediate observer. I bought this book to observe these objects again. q I am an advance observer. I bought this book to add to my collect and/or re-observe these objects again. The book I'm registering is: q SAC's 110 Best of the NGC q Messier Logbook q I would like to purchase a copy of Herschel 400 book when it becomes available. Club Name: __________________________________________ Your Name: __________________________________________ Address: ____________________________________________ City: __________________ State: ____ Zip Code: _________ Mail this to: or E-mail it to: Paul Dickson 7714 N 36th Ave [email protected] Phoenix, AZ 85051-6401 After Observing the Messier Catalog, Try this Observing List: SAC's 110 Best of the NGC [email protected] http://www.seds.org/pub/info/newsletters/sacnews/html/sac.110.best.ngc.html SAC's 110 Best of the NGC is an observing list of some of the best objects after those in the Messier Catalog. -
X-Ray Spectral Survey with XMM–Newton of a Complete Sample of Nearby Seyfert Galaxies
A&A 446, 459–470 (2006) Astronomy DOI: 10.1051/0004-6361:20053893 & c ESO 2006 Astrophysics X-ray spectral survey with XMM–Newton of a complete sample of nearby Seyfert galaxies M. Cappi1, F. Panessa2, L. Bassani1,M.Dadina1, G. DiCocco1, A. Comastri3, R. Della Ceca4, A. V. Filippenko5, F. Gianotti1,L.C.Ho6, G. Malaguti1,J.S.Mulchaey6,G.G.C.Palumbo7, E. Piconcelli8,W.L.W.Sargent9, J. Stephen1, M. Trifoglio1, and K. A. Weaver10 1 INAF-IASF Sezione di Bologna, via Gobetti 101, 40129 Bologna, Italy e-mail: [email protected] 2 Instituto de Fisica de Cantabria (CSIC-UC), Avda de los Castros, 39005 Santander, Spain 3 INAF- Osservatorio Astronomico di Bologna, via Ranzani 1, 40127 Bologna, Italy 4 INAF- Osservatorio Astronomico di Brera, via Brera 28, 20121 Milano, Italy 5 Department of Astronomy, University of California, Berkeley, CA 94720-3411, USA 6 Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101, USA 7 Dipartimento di Astronomia, Universita’ degli Studi di Bologna, via Ranzani 1, 40127 Bologna, Italy 8 XMM–Newton Science Operation Center/RSSD-ESA, Apartado 50727, 28080 Madrid, Spain 9 Department of Astronomy, California Institute of Technology, Pasadena, CA 91125, USA 10 Laboratory for High Energy Astrophysics, NASA’s Goddard Space Flight Center, Greenbelt, MD 20771, USA Received 23 July 2005 / Accepted 28 September 2005 ABSTRACT Results obtained from an X-ray spectral survey of nearby Seyfert galaxies using XMM–Newton are reported. The sample was optically selected, well defined, complete in B magnitude, and distance limited: it consists of the nearest (D ∼< 22 Mpc) 27 Seyfert galaxies (9 of type 1, 18 of type 2) taken from the Ho et al. -
X-Ray Nature of the LINER Nuclear Sources O
A&A 460, 45–57 (2006) Astronomy DOI: 10.1051/0004-6361:20054756 & c ESO 2006 Astrophysics X-ray nature of the LINER nuclear sources O. González-Martín1, J. Masegosa1, I. Márquez1,M.A.Guerrero1, and D. Dultzin-Hacyan2 1 Instituto de Astrofísica de Andalucía, CSIC, Apartado Postal 3004, 18080 Granada, Spain e-mail: [email protected] 2 Instituto de Astronomía, UNAM, Apartado Postal 70-264, 04510 México D.F., México Received 22 December 2005 / Accepted 17 May 2006 ABSTRACT We report the results from a homogeneous analysis of the X-ray (Chandra ACIS) data available for a sample of 51 LINER galaxies selected from the catalogue by Carrillo et al. (1999, Rev. Mex. Astron. Astrofis., 35, 187) and representative of the population of bright LINER sources. The nuclear X-ray morphology has been classified by their nuclear compactness in the hard band (4.5– 8.0 keV) into 2 categories: active galactic nuclei (AGN) candidates (with a clearly identified unresolved nuclear source) and starburst (SB) candidates (without a clear nuclear source). Sixty percent of the total sample are classified as AGNs, with a median luminosity 40 −1 of LX(2−10 keV) = 2.5 × 10 erg s , which is an order of magnitude higher than for SB-like nuclei. The spectral fitting allows us to conclude that most of the objects need a non-negligible power-law contribution. When no spectral fitting can be performed (data with a low signal-to-noise ratio), the color–color diagrams allow us to roughly estimate physical parameters, such as column density, temperature of the thermal model, or spectral index for a power-law, and therefore to better constrain the origin of the X-ray emission. -
The HST View of the Innermost Narrow Line Region
A&A 586, A48 (2016) Astronomy DOI: 10.1051/0004-6361/201526927 & c ESO 2016 Astrophysics The HST view of the innermost narrow line region Barbara Balmaverde1;2, Alessandro Capetti3, Daria Moisio3, Ranieri D. Baldi4;5, and Alessandro Marconi1;2 1 Dipartimento di Fisica e Astronomia, Universitàa˘ di Firenze, via G. Sansone 1, 50019 Sesto Fiorentino (Firenze), Italy e-mail: [email protected] 2 INAF–Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy 3 INAF–Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy 4 Department of Physics, Technion, 3200 Haifa, Israel 5 Department of Physics and Astronomy, The University, Southampton SO17 1BJ, UK Received 10 July 2015 / Accepted 25 November 2015 ABSTRACT We analyze the properties of the innermost narrow line region in a sample of low-luminosity AGN. We select 33 LINERs (bona fide AGN) and Seyfert galaxies from the optical spectroscopic Palomar survey observed by HST/STIS. We find that in LINERs the [N II] and [O I] lines are broader than the [S II] line and that the [N II] /[S II] flux ratio increases when moving from ground-based to HST spectra. This effect is more pronounced considering the wings of the lines. Our interpretation is that, as a result of superior HST spatial resolution, we isolate a compact region of dense ionized gas in LINERs, located at a typical distance of ∼3 pc and with a gas density of ∼104–105 cm−3, which we identify with the outer portion of the intermediate line region (ILR). Instead, we do not observe these kinds of effects in Seyferts; this may be the result of a stronger dilution from the NLR emission, since the HST slit maps a larger region in these sources. -
Vera Rubin's Excellent 1983 Science Article on Dark Matter
24 June 1983, Volume 220, Number 4604 SCIENCE the galaxy carries the stars toward the observer, spectral lines are shifted to- ward the blue region of the spectrum with respect to the central velocity. On the opposite side, where rotation carries The Rotation of Spiral Gala3Kies the stars away from the observer, lines are shifted toward the red spectral re- Vera C. ]Rubin gion.Several years later, Pease (8) convinc- ingly illustrated that rotation was respon- sible for the inclined lines. Using the 60- inch telescope on Mount Wilson during Historians of astronomy may some um, Scheiner correctly concluded that the months of August, September, and day call the mid-20th century the era of the nucleus of M31 w;as a stellar system October 1917, he patiently acquited a 79- Downloaded from galaxies. During those years, astrono- composed of stars li1 ce the sun, rather hour exposure. of the spectrum of the mers made significant progress in under- than a gaseous object. nuclear region of M3 1 with the slit standing the structure, formation, and Even earlier, LordIand Lady Huggins aligned along the apparent major axis of evolution of galaxies. In this article, I (4) had attempted at tlheir private obser- the galaxy. Inclined lines appeared. A will discuss a few selected early steps in vatory to obtain a spectrum of M3 1, but second exposure made during these 3 determining the internal dynamics of gal- their labors were frauight with disaster. months in 1918, with the slit placed per- http://science.sciencemag.org/ axies, as well as current research con- Exposure times were so long that each pendicular- to the major axis along the cerning the rotation and mass distribu- fall when M31 was overhead they would apparent minor axis, showed no inclina- tion within galaxies. -
Astro-Ph/0211002V1 1 Nov 2002 Aayi Nipratpoet Htms Eex- Be Must That Property Important an Is Galaxy Introduction 1
The Ringed Spiral Galaxy NGC 4622. I. Photometry, Kinematics, and the Case for Two Strong Leading Outer Spiral Arms1 Ronald J. Buta2 and Gene G. Byrd Department of Physics & Astronomy Department, University of Alabama, Tuscaloosa, AL 35487, USA and Tarsh Freeman Bevill State Community College, Fayette, AL, USA ABSTRACT The intriguing nearly face-on southern ringed spiral galaxy NGC 4622, the first galaxy defini- tively shown to have leading spiral structure, is revisited in this paper with new images from the Hubble Space Telescope’s WFPC2, together with ground-based optical and near-IR imaging, and a Fabry-Perot Hα velocity field. The data provide new information on the disk/bulge/halo mix, rotation curve, star formation in the galaxy, and the sense of winding of its prominent spiral arms. Previously, we suggested that the weaker, inner single arm most likely has the leading sense, based on a numerical simulation. Now, taking advantage of HST resolution and using de Vaucouleurs’ standard extinction and reddening technique to determine the near side of the galaxy’s slightly tilted disk, we come to the more surprising conclusion that the two strong outer arms have the leading sense. We suggest that this highly unusual configuration may be the result of a past minor merger or mild tidal encounter. Possible evidence for a minor merger is found in a short, central dust lane, although this is purely circumstantial and an unrelated interaction with a different companion could also be relevant. The leading arms may be allowed to persist because NGC 4622 is dark halo-dominated (i.e., not “maximum disk” in the inner regions) and displays a significantly rising rotation curve. -
Molecular Gas in Virgo Cluster Spiral Galaxies
University of Massachusetts Amherst ScholarWorks@UMass Amherst Doctoral Dissertations 1896 - February 2014 1-1-1987 Molecular gas in Virgo Cluster spiral galaxies. Jeffrey D. Kenney University of Massachusetts Amherst Follow this and additional works at: https://scholarworks.umass.edu/dissertations_1 Recommended Citation Kenney, Jeffrey D., "Molecular gas in Virgo Cluster spiral galaxies." (1987). Doctoral Dissertations 1896 - February 2014. 1756. https://scholarworks.umass.edu/dissertations_1/1756 This Open Access Dissertation is brought to you for free and open access by ScholarWorks@UMass Amherst. It has been accepted for inclusion in Doctoral Dissertations 1896 - February 2014 by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. MOLECULAR GAS IN VIRGO CLUSTER SPIRAL GALAXIES A Dissertation Presented by Jeffrey D. Kenney Submitted to the Graduate School of the University of Massachusetts in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 1987 Department of Physics and Astronomy Copyright ® 1987 by Jeffrey D. Kenney All rights reserved ii Molecular Gas in Virgo Cluster Spiral Galaxies A. Dissertation Presented by Jeffrey D. Kenney Approved as to style and content by; Ji^dith S. Young, Ciiairpe^son William A. Dent, Member . Peter Schloerb, Member Stevan7^ E. Strom, Member Robert V. Krotkov, Outside Member Martha P. Hay ne^, Outs ide Member Robert Hal lock, Department Head Department of Physics and Astronomy 111 ACKNOWLEDGEMENTS -
Structure, Mass and Distance of the Virgo Cluster from a Tolman-Bondi
A&A manuscript no. ASTRONOMY (will be inserted by hand later) AND Your thesaurus codes are: 03(11.03.4; 11.04.1; 11.05.1; 11.06.2; 11.19.2; 12.04.3) ASTROPHYSICS Structure, mass and distance of the Virgo cluster from a Tolman-Bondi model Pascal Fouqu´e1,2, Jos´eM. Solanes3, Teresa Sanchis4, and Chantal Balkowski5 1 Observatoire de Paris-Meudon DESPA, F-92195 Meudon CEDEX, France 2 European Southern Observatory, Casilla 19001, Santiago 19, Chile email: [email protected] 3 Departament d’Enginyeria Inform`atica i Matem`atiques, Escola T`ecnica Superior d’Enginyeria, Universitat Rovira i Virgili, Carretera de Salou, s/n; E–43006 Tarragona, Spain email: [email protected] 4 Departament d’Astronomia i Meteorologia, Facultat de F´ısiques, Universitat de Barcelona C/ Mart´ı i Franqu´es 1; E– 08028 Barcelona, Spain email: [email protected] 5 Observatoire de Paris-Meudon DAEC, F-92195 Meudon CEDEX, France email: [email protected] Received / Accepted Abstract. We have applied a relativistic Tolman-Bondi 1. Introduction model of the Virgo cluster to a sample of 183 galaxies with measured distances within a radius of 8 degrees from M 87. In 1990, Fouqu´eet al. (1990) derived an unbiased dis- We find that the sample is significantly contaminated by tance to the Virgo cluster, based on a complete sample background galaxies which lead to too large a cluster mean of 178 spiral galaxies, using the B-band Tully-Fisher re- distance if not excluded. The Tolman-Bondi model predic- lation (Tully & Fisher 1977). -
A Classical Morphological Analysis of Galaxies in the Spitzer Survey Of
Accepted for publication in the Astrophysical Journal Supplement Series A Preprint typeset using LTEX style emulateapj v. 03/07/07 A CLASSICAL MORPHOLOGICAL ANALYSIS OF GALAXIES IN THE SPITZER SURVEY OF STELLAR STRUCTURE IN GALAXIES (S4G) Ronald J. Buta1, Kartik Sheth2, E. Athanassoula3, A. Bosma3, Johan H. Knapen4,5, Eija Laurikainen6,7, Heikki Salo6, Debra Elmegreen8, Luis C. Ho9,10,11, Dennis Zaritsky12, Helene Courtois13,14, Joannah L. Hinz12, Juan-Carlos Munoz-Mateos˜ 2,15, Taehyun Kim2,15,16, Michael W. Regan17, Dimitri A. Gadotti15, Armando Gil de Paz18, Jarkko Laine6, Kar´ın Menendez-Delmestre´ 19, Sebastien´ Comeron´ 6,7, Santiago Erroz Ferrer4,5, Mark Seibert20, Trisha Mizusawa2,21, Benne Holwerda22, Barry F. Madore20 Accepted for publication in the Astrophysical Journal Supplement Series ABSTRACT The Spitzer Survey of Stellar Structure in Galaxies (S4G) is the largest available database of deep, homogeneous middle-infrared (mid-IR) images of galaxies of all types. The survey, which includes 2352 nearby galaxies, reveals galaxy morphology only minimally affected by interstellar extinction. This paper presents an atlas and classifications of S4G galaxies in the Comprehensive de Vaucouleurs revised Hubble-Sandage (CVRHS) system. The CVRHS system follows the precepts of classical de Vaucouleurs (1959) morphology, modified to include recognition of other features such as inner, outer, and nuclear lenses, nuclear rings, bars, and disks, spheroidal galaxies, X patterns and box/peanut structures, OLR subclass outer rings and pseudorings, bar ansae and barlenses, parallel sequence late-types, thick disks, and embedded disks in 3D early-type systems. We show that our CVRHS classifications are internally consistent, and that nearly half of the S4G sample consists of extreme late-type systems (mostly bulgeless, pure disk galaxies) in the range Scd-Im.