The Hot, Warm and Cold Gas in Arp 227 - an Evolving Poor Group R
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Infrared Spectroscopy of Nearby Radio Active Elliptical Galaxies
The Astrophysical Journal Supplement Series, 203:14 (11pp), 2012 November doi:10.1088/0067-0049/203/1/14 C 2012. The American Astronomical Society. All rights reserved. Printed in the U.S.A. INFRARED SPECTROSCOPY OF NEARBY RADIO ACTIVE ELLIPTICAL GALAXIES Jeremy Mould1,2,9, Tristan Reynolds3, Tony Readhead4, David Floyd5, Buell Jannuzi6, Garret Cotter7, Laura Ferrarese8, Keith Matthews4, David Atlee6, and Michael Brown5 1 Centre for Astrophysics and Supercomputing Swinburne University, Hawthorn, Vic 3122, Australia; [email protected] 2 ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) 3 School of Physics, University of Melbourne, Melbourne, Vic 3100, Australia 4 Palomar Observatory, California Institute of Technology 249-17, Pasadena, CA 91125 5 School of Physics, Monash University, Clayton, Vic 3800, Australia 6 Steward Observatory, University of Arizona (formerly at NOAO), Tucson, AZ 85719 7 Department of Physics, University of Oxford, Denys, Oxford, Keble Road, OX13RH, UK 8 Herzberg Institute of Astrophysics Herzberg, Saanich Road, Victoria V8X4M6, Canada Received 2012 June 6; accepted 2012 September 26; published 2012 November 1 ABSTRACT In preparation for a study of their circumnuclear gas we have surveyed 60% of a complete sample of elliptical galaxies within 75 Mpc that are radio sources. Some 20% of our nuclear spectra have infrared emission lines, mostly Paschen lines, Brackett γ , and [Fe ii]. We consider the influence of radio power and black hole mass in relation to the spectra. Access to the spectra is provided here as a community resource. Key words: galaxies: elliptical and lenticular, cD – galaxies: nuclei – infrared: general – radio continuum: galaxies ∼ 1. INTRODUCTION 30% of the most massive galaxies are radio continuum sources (e.g., Fabbiano et al. -
Magnificent Spiral Galaxy Is Being Stretched by Passing Neighbor 27 May 2021, by Ray Villard
Magnificent spiral galaxy is being stretched by passing neighbor 27 May 2021, by Ray Villard animals—the gingham dog and calico cat—who got into a spat and ate each other. It's not so dramatic in this case. The galaxies are only getting a little chewed up because of their close proximity. The magnificent spiral galaxy NGC 2276 looks a bit lopsided in this Hubble Space Telescope snapshot. A bright hub of older yellowish stars normally lies directly in the center of most spiral galaxies. But the bulge in NGC 2276 looks offset to the upper left. What's going on? In reality, a neighboring galaxy to the right of NGC 2276 (NGC 2300, not seen here) is gravitationally tugging on its disk of blue stars, pulling the stars on one side of the galaxy outward to distort the galaxy's normal fried-egg appearance. This sort of "tug of war" between galaxies that pass close enough to feel each other's gravitational pull is not uncommon in the universe. But, like Credit: NASA, ESA, STScI, Paul Sell (University of snowflakes, no two close encounters look exactly Florida) alike. In addition, newborn and short-lived massive stars form a bright, blue arm along the upper left edge of The myriad spiral galaxies in our universe almost NGC 2276. They trace out a lane of intense star all look like fried eggs. A central bulge of aging formation. This may have been triggered by a prior stars is like the egg yolk, surrounded by a disk of collision with a dwarf galaxy. -
The Newsletter of the Barnard-Seyfert Astronomical Society
March The ECLIPSE 2018 The Newsletter of the Barnard-Seyfert Astronomical Society From the President Next Membership Meeting: Greetings, March 21, 2018, 7:30 pm February 2018 was no friend of BSAS weather wise. Te short Cumberland Valley month of February was not short on rain. We saw 18 or 19 Girl Scout Council Building days with measurable participation. Average monthly rainfall 4522 Granny White Pike in February for Nashville is 3.7 inches. We had just under 11 inches. When it wasn’t raining it was cloudy and windy. Topic: Equipment Tune-up Details on page 6. We had enough bad weather to frustrate almost all attempts to view the winter stars and deep sky objects we believe are still up there. Our public star party at Edwin Warner Park was washed out, as was the private star party on the Natchez In this Issue: Trace at Water Valley Overlook. May we turn the page on that trend? Observing Highlights 2 Tanks to Terry Reeves for his informative and helpful From A Certain Point of View presentation, All About A Messier Marathon, which he gave reviewed by Robin Byrne 3 at this month’s member meeting. We will have a chance to put that information into practice on Saturday, March 17th Deep Sky Daze when BSAS holds a Messier Marathon at Mark Manner’s by Mike Benson 4 Spot Observatory. Just in case, we are planning April 14th as Board Meeting Minutes 8 a backup date. We have that date reserved for a private star February 7, 2018 party at Water Valley Overlook. -
Stellar Population Gradient in Lenticular Galaxies: NGC 1023, NGC 3115 and NGC 4203
A&A 410, 803–812 (2003) Astronomy DOI: 10.1051/0004-6361:20031261 & c ESO 2003 Astrophysics Stellar population gradient in lenticular galaxies: NGC 1023, NGC 3115 and NGC 4203 M. Bassin1 and Ch. Bonatto1 Universidade Federal do Rio Grande do Sul, Instituto de F´ısica, CP 15051, Porto Alegre CEP 91501-970, RS, Brazil Received 11 March 2003 / Accepted 2 July 2003 Abstract. We investigate the stellar population content in the lenticular galaxies NGC 1023, NGC 3115 and NGC 4203 applying a population synthesis method based on a seven component spectral basis with different ages – 2.5 106,10 106,25 106,75 106, 200 106,1.2 109 and older than 1010 years, and metallicity in the range 1.3 ×[Z/Z ] × 0.2. This× study employs× two-dimensional× × STIS spectra in the range λλ2900–5700 Å, obtained from the Hubble− ≤ Space Telescope ≤− public archives. We extracted one-dimensional spectra in adjacent windows 100 pc wide (projected distance) from the nuclear regions up to 300–400 pc. The largest contribution, both in λ5870 Å flux and mass fraction, comes from old stars (age > 1010 years). We verified the possible existence of circumnuclear bursts (CNBs) in NGC 3115 and NGC 4203. Key words. galaxies: elliptical and lenticular, cD – galaxies: stellar content – galaxies: nuclei 1. Introduction the purpose of determining the star formation history in galax- ies based on integrated properties. A precise determination of properties of the stellar content of Two main approaches have been considered: evolutionary galaxies is clearly an important issue, since they are related synthesis, a technique to study the spectrophotometric evolu- to the galaxy formation and evolution. -
IRAC Near-Infrared Features in the Outer Parts of S4G Galaxies
Mon. Not. R. Astron. Soc. 000, 1{26 (2014) Printed 15 June 2018 (MN LATEX style file v2.2) Spitzer/IRAC Near-Infrared Features in the Outer Parts of S4G Galaxies Seppo Laine,1? Johan H. Knapen,2;3 Juan{Carlos Mu~noz{Mateos,4:5 Taehyun Kim,4;5;6;7 S´ebastienComer´on,8;9 Marie Martig,10 Benne W. Holwerda,11 E. Athanassoula,12 Albert Bosma,12 Peter H. Johansson,13 Santiago Erroz{Ferrer,2;3 Dimitri A. Gadotti,5 Armando Gil de Paz,14 Joannah Hinz,15 Jarkko Laine,8;9 Eija Laurikainen,8;9 Kar´ınMen´endez{Delmestre,16 Trisha Mizusawa,4;17 Michael W. Regan,18 Heikki Salo,8 Kartik Sheth,4;1;19 Mark Seibert,7 Ronald J. Buta,20 Mauricio Cisternas,2;3 Bruce G. Elmegreen,21 Debra M. Elmegreen,22 Luis C. Ho,23;7 Barry F. Madore7 and Dennis Zaritsky24 1Spitzer Science Center - Caltech, MS 314-6, Pasadena, CA 91125, USA 2Instituto de Astrof´ısica de Canarias, E-38205 La Laguna, Tenerife, Spain 3Departamento de Astrof´ısica, Universidad de La Laguna, 38206 La Laguna, Spain 4National Radio Astronomy Observatory/NAASC, Charlottesville, 520 Edgemont Road, VA 22903, USA 5European Southern Observatory, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago, Chile 6Astronomy Program, Department of Physics and Astronomy, Seoul National University, Seoul 151-742, Korea 7The Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101, USA 8Division of Astronomy, Department of Physics, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland 9Finnish Centre of Astronomy with ESO (FINCA), University of Turku, V¨ais¨al¨antie20, FIN-21500 Piikki¨o 10Max-Planck Institut f¨urAstronomie, K¨onigstuhl17 D-69117 Heidelberg, Germany 11Leiden Observatory, Leiden University, P.O. -
Arxiv:1311.4559V1 [Astro-Ph.GA] 18 Nov 2013 Od(
Draft version June 25, 2018 A Preprint typeset using LTEX style emulateapj v. 5/2/11 A DEEP SEARCH FOR FAINT GALAXIES ASSOCIATED WITH VERY LOW-REDSHIFT C IV ABSORBERS: A CASE WITH COLD-ACCRETION CHARACTERISTICS* Joseph N. Burchett1,2, Todd M. Tripp2, Jessica K. Werk3, J. Christopher Howk4, J. Xavier Prochaska3, Amanda Brady Ford5, and Romeel Dave´6,7,8 Draft version June 25, 2018 ABSTRACT Studies of QSO absorber-galaxy connections are often hindered by inadequate information on whether faint/dwarf galaxies are located near the QSO sight lines. To investigate the contribution of faint galaxies to QSO absorber populations, we are conducting a deep galaxy redshift survey near low−z C IV absorbers. Here we report a blindly-detected C IV absorption system (zabs =0.00348) in the spectrum of PG1148+549 that appears to be associated either with an edge-on dwarf galaxy with an obvious disk (UGC 6894, zgal = 0.00283) at an impact parameter of ρ = 190 kpc or with a very faint dwarf irregular galaxy at ρ = 23 kpc, which is closer to the sightline but has a larger redshift difference (zgal =0.00107, i.e., δv =724 km/s). We consider various gas/galaxy associations, includ- ing infall and outflows. Based on current theoretical models, we conclude that the absorber is most likely tracing (1) the remnants of an outflow from a previous epoch, a so-called ancient outflow, or (2) intergalactic gas accreting onto UGC 6894, cold mode accretion. The latter scenario is supported by H I synthesis imaging data that shows the rotation curve of the disk being codirectional with the velocity offset between UGC6894 and the absorber, which is located almost directly along the major axis of the edge-on disk. -
Application of the Global Modal Approach to Spiral Galaxies
Astronomy & Astrophysics manuscript no. paper˙1astroph July 20, 2021 (DOI: will be inserted by hand later) Application of the global modal approach to spiral galaxies V. Korchagin1,2, N. Orlova2, N. Kikuchi3, S. M. Miyama4 and A. Moiseev5 1 Yale University, New Haven, Connecticut 06520-8101, USA e-mail: [email protected] 2 Institute of Physics, Stachki 194, Rostov-on-Don, Russia e-mail: [email protected] 3 Earth Observation Research Center, National Space Development Agency of Japan, 1-8-10 Harurau, Chuo-ku, Tokyo 104-6023, Japan e-mail: [email protected] 4 National Astronomical Observatory, Mitaka, Tokyo 181–8588, Japan e-mail: [email protected] 5 Special Astrophysical Observatory of Russian AS, Nizhnij Arkhyz 369167, Russia e-mail: [email protected] received; accepted Abstract. We have tested the applicability of the global modal approach in the density wave theory of spiral structure for a sample of six spiral galaxies: NGC 488, NGC 628, NGC 1566, NGC 2985, NGC 3938 and NGC 6503. The galaxies demonstrate a variety of spiral patterns from the regular open and tightly wound spiral patterns to a multi-armed spiral structure. Using the observed radial distributions of the stellar velocity dispersions and the rotation curves we have constructed equilibrium models for the galactic disks in each galaxy and analyzed the dynamics of the spiral perturbations using linear global modal analysis and nonlinear hydrodynamical simulations. The theory reproduces qualitatively the observed properties of the spiral arms in the galactic disks. Namely the theory predicts observed grand-design spiral structure in the galaxy NGC 1566, the tightly-wound spirals in galaxies NGC 488 and NGC 2985, the two-armed spiral pattern with the third spiral arm in the galaxy NGC 628, and the multi-armed spiral structure in the galaxies NGC 3938 and NGC 6503. -
International Astronomical Union Commission 42 BIBLIOGRAPHY of CLOSE BINARIES No. 93
International Astronomical Union Commission 42 BIBLIOGRAPHY OF CLOSE BINARIES No. 93 Editor-in-Chief: C.D. Scarfe Editors: H. Drechsel D.R. Faulkner E. Kilpio E. Lapasset Y. Nakamura P.G. Niarchos R.G. Samec E. Tamajo W. Van Hamme M. Wolf Material published by September 15, 2011 BCB issues are available via URL: http://www.konkoly.hu/IAUC42/bcb.html, http://www.sternwarte.uni-erlangen.de/pub/bcb or http://www.astro.uvic.ca/∼robb/bcb/comm42bcb.html The bibliographical entries for Individual Stars and Collections of Data, as well as a few General entries, are categorized according to the following coding scheme. Data from archives or databases, or previously published, are identified with an asterisk. The observation codes in the first four groups may be followed by one of the following wavelength codes. g. γ-ray. i. infrared. m. microwave. o. optical r. radio u. ultraviolet x. x-ray 1. Photometric data a. CCD b. Photoelectric c. Photographic d. Visual 2. Spectroscopic data a. Radial velocities b. Spectral classification c. Line identification d. Spectrophotometry 3. Polarimetry a. Broad-band b. Spectropolarimetry 4. Astrometry a. Positions and proper motions b. Relative positions only c. Interferometry 5. Derived results a. Times of minima b. New or improved ephemeris, period variations c. Parameters derivable from light curves d. Elements derivable from velocity curves e. Absolute dimensions, masses f. Apsidal motion and structure constants g. Physical properties of stellar atmospheres h. Chemical abundances i. Accretion disks and accretion phenomena j. Mass loss and mass exchange k. Rotational velocities 6. Catalogues, discoveries, charts a. -
Understanding the H2/HI Ratio in Galaxies 3
Mon. Not. R. Astron. Soc. 394, 1857–1874 (2009) Printed 6 August 2021 (MN LATEX style file v2.2) Understanding the H2/HI Ratio in Galaxies D. Obreschkow and S. Rawlings Astrophysics, Department of Physics, University of Oxford, Keble Road, Oxford, OX1 3RH, UK Accepted 2009 January 12 ABSTRACT galaxy We revisit the mass ratio Rmol between molecular hydrogen (H2) and atomic hydrogen (HI) in different galaxies from a phenomenological and theoretical viewpoint. First, the local H2- mass function (MF) is estimated from the local CO-luminosity function (LF) of the FCRAO Extragalactic CO-Survey, adopting a variable CO-to-H2 conversion fitted to nearby observa- 5 1 tions. This implies an average H2-density ΩH2 = (6.9 2.7) 10− h− and ΩH2 /ΩHI = 0.26 0.11 ± · galaxy ± in the local Universe. Second, we investigate the correlations between Rmol and global galaxy properties in a sample of 245 local galaxies. Based on these correlations we intro- galaxy duce four phenomenological models for Rmol , which we apply to estimate H2-masses for galaxy each HI-galaxy in the HIPASS catalog. The resulting H2-MFs (one for each model for Rmol ) are compared to the reference H2-MF derived from the CO-LF, thus allowing us to determine the Bayesian evidence of each model and to identify a clear best model, in which, for spi- galaxy ral galaxies, Rmol negatively correlates with both galaxy Hubble type and total gas mass. galaxy Third, we derive a theoretical model for Rmol for regular galaxies based on an expression for their axially symmetric pressure profile dictating the degree of molecularization. -
1987Apj. . .320. .2383 the Astrophysical Journal, 320:238-257
.2383 The Astrophysical Journal, 320:238-257,1987 September 1 © 1987. The American Astronomical Society. AU rights reserved. Printed in U.S.A. .320. 1987ApJ. THE IRÁS BRIGHT GALAXY SAMPLE. II. THE SAMPLE AND LUMINOSITY FUNCTION B. T. Soifer, 1 D. B. Sanders,1 B. F. Madore,1,2,3 G. Neugebauer,1 G. E. Danielson,4 J. H. Elias,1 Carol J. Lonsdale,5 and W. L. Rice5 Received 1986 December 1 ; accepted 1987 February 13 ABSTRACT A complete sample of 324 extragalactic objects with 60 /mi flux densities greater than 5.4 Jy has been select- ed from the IRAS catalogs. Only one of these objects can be classified morphologically as a Seyfert nucleus; the others are all galaxies. The median distance of the galaxies in the sample is ~ 30 Mpc, and the median 10 luminosity vLv(60 /mi) is ~2 x 10 L0. This infrared selected sample is much more “infrared active” than optically selected galaxy samples. 8 12 The range in far-infrared luminosities of the galaxies in the sample is 10 LQ-2 x 10 L©. The far-infrared luminosities of the sample galaxies appear to be independent of the optical luminosities, suggesting a separate luminosity component. As previously found, a correlation exists between 60 /¿m/100 /¿m flux density ratio and far-infrared luminosity. The mass of interstellar dust required to produce the far-infrared radiation corre- 8 10 sponds to a mass of gas of 10 -10 M0 for normal gas to dust ratios. This is comparable to the mass of the interstellar medium in most galaxies. -
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. -
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.