DOCSLIB.ORG

Ultra-Luminous X-Ray Sources in Nearby Galaxies from ROSAT HRI Observations I. Data Analysis

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Ultra-Luminous X-Ray Sources in Nearby Galaxies from ROSAT HRI Observations I. Data Analysis Submitted to ApJ Supplement Ultra-luminous X-ray Sources in nearby galaxies from ROSAT HRI observations I. data analysis Ji-Feng Liu and Joel N. Bregman Astronomy Department, University of Michigan, MI 48109 ABSTRACT X-ray observations have revealed in other galaxies a class of extra-nuclear X-ray point sources with X-ray luminosities of 1039–1041 erg/sec, exceeding the Eddington luminosity for stellar mass X-ray binaries. These ultra-luminous X- ray sources (ULXs) may be powered by intermediate mass black hole of a few thousand M⊙ or stellar mass black holes with special radiation processes. In this ′ paper, we present a survey of ULXs in 313 nearby galaxies with D25>1 within 40 Mpc with 467 ROSAT HRI archival observations. The HRI observations are reduced with uniform procedures, refined by simulations that help define the point source detection algorithm employed in this survey. A sample of 562 38 43 extragalactic X-ray point sources with LX = 10 –10 erg/sec is extracted from 173 survey galaxies, including 106 ULX candidates within the D25 isophotes of 63 galaxies and 110 ULX candidates between 1–2 D25 of 64 galaxies, from × which a clean sample of 109 ULXs is constructed to minimize the contamination from foreground or background objects. The strong connection between ULXs and star formation is confirmed based on the striking preference of ULXs to arXiv:astro-ph/0501309v1 14 Jan 2005 occur in late-type galaxies, especially in star forming regions such as spiral arms. ULXs are variable on time scales over days to years, and exhibit a variety of long term variability patterns. The identifications of ULXs in the clean sample show some ULXs identified as supernovae (remnants), HII regions/nebulae, or young massive stars in star forming regions, and a few other ULXs identified as old globular clusters. In a subsequent paper, the statistic properties of the survey will be studied to calculate the occurrence frequencies and luminosity functions for ULXs in different types of galaxies to shed light on the nature of these enigmatic sources. Subject headings: catalogs – galaxies: general – X-rays: binaries – X-rays: galax- ies –2– 1. INTRODUCTION Ultra-luminous X-ray sources (ULXs) are extra-nuclear sources with luminosities in the range of 1039 1041 erg/sec in other galaxies, and have been observed by ROSAT, ASCA, − recently by XMM-Newton and Chandra Observatory in large numbers. As compared to the cases of the X-ray binaries in our Galaxy, which are powered by accretion onto neutron stars or stellar mass black holes and have luminosities of 1033 1038 erg/sec, the luminosities of 3 − 4 −2 ULXs require accreting compact objects of masses 10 – 10 M⊙ if they emit at 10 of the Eddington luminosity, typical of Galactic X-ray binaries. While the required masses could be much larger if they emit at much less than 10−2 of the Eddington luminosity, as in the cases of some low luminosity active galactic nuclei (AGN), the masses cannot be much greater than 5 10 M⊙ for these extra-nuclear sources to survive the dynamic friction over a few Gigayears (Colbert 1999). Such intermediate mass compact objects can only be black holes, and if they exist, are the missing links between stellar mass black holes and super-massive black holes in the nuclei of galaxies. While the explanation with intermediate mass black holes is simple, intriguing and astrophysically interesting, such black holes are not predicted by ordinary stellar evolution theories. It is suggested that black holes of a few hundred M⊙ can form from the death of Pop III stars, and more massive ones might form from multiple stellar interactions in some dense clusters, hencing manifest as ultra-luminous X-ray sources (Portegies Zwart et al. 2002). Alternatively, these X-ray sources could be stellar mass black holes or neutron stars whose apparent super-Eddington luminosities are due to some special processes. One suggestion is that radiation pressure-dominated accretion disks with photon-bubble instabilities are able to emit truly super-Eddington luminosities (Begelman 2002). Another suggestion is that beaming effects can produce the observed luminosities of ULXs (King et al. 2001). The leading goals in ULX studies are to determine the masses of the primary, to under- stand how and where they form, and to find out how they emit at such high luminosities. In the last few years many efforts have been made to address these questions, and important clues have been revealed. However, these studies mainly focus on some well-known objects and galaxies (e.g., M81 X-9, NGC5204 X-1, Antenna galaxy, Cartwheel galaxy) except for a few works (e.g., Colbert & Ptak, 2002, hereafter CP2002; Swartz et al. 2004; Ptak & Colbert 2004), and now it is time to define a complete sample of ULXs to study the properties of the phenomenon and test critical ideas. One resource to rely on for this purpose is the data archive of the ROSAT High Resolution Imager (HRI), which includes 5403 observations in the ten years from June 1990 to February 1999. The HRI is a multichannel plate detector of 38′ 38′ square field of view, large enough to contain all individual nearby galaxies other × than LMC, SMC, M31, and M33 in our Local Group. Its spatial resolution is suitable for –3– extra-galactic point source studies, with on-axis FWHM < 5′′ and a pixel scale of 0.′′5/pixel, adequate to resolve point sources in most cases. Also, the archival observations have rea- sonable sky coverage for survey purposes. For example, the 5393 pointed HRI observations used in the First ROSAT HRI Source Catalog (1RXH; ROSAT scientific team, 2000) covers about 2% of the sky. The large database of ROSAT HRI observations has not been thoroughly exploited for complete samples of ULXs in nearby galaxies. Roberts & Warwick (2000; hereafter RW2000) have used the HRI archive to study the X-ray properties of nearby galaxies, and detected in 83 galaxies 187 discrete X-ray sources of all luminosity ranges, among which 27 non- 39 nuclear sources have LX >10 erg/sec and can be taken as ULXs. They used the nearby galaxy sample by Ho, Filippenko & Sargent (1995), which was constructed to search for dwarf Seyfert nuclei in nearby galaxies and contains 486 bright northern galaxies. Many nearby galaxies with HRI observations are not included in this sample, and the HRI archive is far from being fully utilized for surveying ULX. Recently Colbert & Ptak (2002) made an effort to analyze the HRI observations to search for ULXs in a sample of 9999 galaxies in the Third Reference Catalog of galaxies (RC3; de Vaucouleurs et al. 1991) with cz<5000 km/sec. They found 87 ULXs in 54 galaxies, with 37 in early-type galaxies. However, many ULXs in the CP2002 catalog are projected far from the host galaxies, and may be false ULXs from foreground stars or background AGN/QSOs. For example, Irwin et al. (2004) pointed out that the radial distribution of ULXs in early-type galaxies in the CP2002 catalog is consistent with a random distribution, thus these ULXs are probably not physically associated with these early-type galaxies. Here we present our study of ULXs in nearby galaxies with the wealth of HRI archive. To fully utilize the HRI archive, we choose all observations associated with any RC3 galaxies within 40 Mpc with isophotal diameters >1 arcminute. The RC3 galaxy sample, the selected HRI observations and the survey galaxies are described in section 2. In our analysis a wavelet algorithm is used for point source detection, and in section 3 we discuss its performance on HRI images through simulations. In section 4, we describe the analysis procedures applied on the data, including the point source detection, the variability tests, astrometric corrections, associations with galaxies and computation of luminosities. These efforts lead to a catalog of 562 extragalactic X-ray sources above 3σ detection within 2 D25 of 173 out of the 313 × survey galaxies, including 106 ULX candidates within the D25 isophotes of 63 galaxies and 110 ULX candidates between 1–2 D25 of 64 galaxies. The identifications of these sources × are given in section 5. As a final product, we construct a clean sample of ULXs to include ULXs within, and a few outside the D25 isophotes, with identified foreground stars and background QSOs excluded. The comments and finding charts are given for these ULXs in section 6. In section 7 we summarize the procedures and preliminary results of the survey. –4– In a subsequent paper, we will study the occurrence rates and luminosity functions for ULXs in different types of galaxies. 2. ROSAT HRI survey of nearby galaxies To search for the ultra-luminous X-ray sources in the nearby galaxies from the ROSAT HRI archival observations, we cross correlated a nearby galaxy sample with the list of HRI archival observations to select observations with nearby galaxies within their field of views. Here we describe the nearby galaxy sample, the selected HRI observations, and the survey galaxy sample. The nearby galaxy sample is extracted from RC3, one of the most complete catalog for nearby galaxies having apparent diameters larger than 1 arcminute at the D25 isophotal level, total B-band magnitudes BT brighter than 15.5, and redshifts not in excess of 15,000 km/sec. Distances to galaxies are collected from the literature, including the HST Key Project (designated as KP; Freedman et al. 2002), the surface brightness fluctuation method (SBF; Tonry et al. 2001), the nearby galaxy flow model by Tully (1992; T92), and the Nearby Galaxy Catalog (T88; Tully 1988).
Load more

Recommended publications
  • 12 Strong Gravitational Lenses
    12 Strong Gravitational Lenses Phil Marshall, MaruˇsaBradaˇc,George Chartas, Gregory Dobler, Ard´ısEl´ıasd´ottir,´ Emilio Falco, Chris Fassnacht, James Jee, Charles Keeton, Masamune Oguri, Anthony Tyson LSST will contain more strong gravitational lensing events than any other survey preceding it, and will monitor them all at a cadence of a few days to a few weeks. Concurrent space-based optical or perhaps ground-based surveys may provide higher resolution imaging: the biggest advances in strong lensing science made with LSST will be in those areas that benefit most from the large volume and the high accuracy, multi-filter time series. In this chapter we propose an array of science projects that fit this bill. We first provide a brief introduction to the basic physics of gravitational lensing, focusing on the formation of multiple images: the strong lensing regime. Further description of lensing phenomena will be provided as they arise throughout the chapter. We then make some predictions for the properties of samples of lenses of various kinds we can expect to discover with LSST: their numbers and distributions in redshift, image separation, and so on. This is important, since the principal step forward provided by LSST will be one of lens sample size, and the extent to which new lensing science projects will be enabled depends very much on the samples generated. From § 12.3 onwards we introduce the proposed LSST science projects. This is by no means an exhaustive list, but should serve as a good starting point for investigators looking to exploit the strong lensing phenomenon with LSST.
    [Show full text]
  • Magellanic Type Galaxies Throughout the Universe Eric M
    The Magellanic System: Stars, Gas, and Galaxies Proceedings IAU Symposium No. 256, 2008 c 2009 International Astronomical Union Jacco Th. van Loon & Joana M. Oliveira, eds. doi:10.1017/S1743921308028871 Magellanic type galaxies throughout the Universe Eric M. Wilcots Department of Astronomy, University of Wisconsin-Madison, 475 N. Charter St., Madison, WI 53706 USA email: [email protected] Abstract. The Magellanic Clouds are often characterized as “irregular” galaxies, a term that implies an overall lack of organized structure. While this may be a fitting description of the Small Cloud, the Large Magellanic Cloud, contrary to popular opinion, should not be considered an irregular galaxy. It is characterized by a distinctive morphology of having an offset stellar bar and single spiral arm. Such morphology is relatively common in galaxies of similar mass throughout the local Universe, although explaining the origin of these features has proven challenging. Through a number of recent studies we are beginning to get a better grasp on what it means to be a Magellanic spiral. One key result of these works is that we now recognize that the most unique aspect of the Magellanic Clouds is not their structure, but, rather, their proximity to a larger spiral such as the Milky Way. Keywords. galaxies: dwarf, galaxies: evolution, galaxies: interactions, Magellanic Clouds, galax- ies: structure 1. Introduction While the Small Magellanic Cloud can properly be thought of as an irregular galaxy, the Large Magellanic Cloud shares a number of key morphological properties with a population of galaxies classified as Barred Magellanic Spirals (SBm). These properties include a stellar bar, the center of which may or may not be coincident with the dynamical center of the galaxy, a single, looping spiral arm, and often a large star-forming complex at one end of the bar.
    [Show full text]
  • Arxiv:Astro-Ph/0407438V1 20 Jul 2004
    The Nature of Nearby Counterparts to Intermediate Redshift Luminous Compact Blue Galaxies I. Optical/H I Properties and Dynamical Masses C. A. Garland1 Institute for Astronomy, University of Hawai‘i, 2680 Woodlawn Drive, Honolulu, HI 96822 [email protected] D. J. Pisano2 CSIRO Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710, Australia [email protected] J. P. Williams Institute for Astronomy, University of Hawai‘i, 2680 Woodlawn Drive, Honolulu, HI 96822 [email protected] R. Guzm´an Department of Astronomy, University of Florida, 211 Bryant Space Science Center, P.O. Box 112055, Gainesville, FL 32611-2055 [email protected] arXiv:astro-ph/0407438v1 20 Jul 2004 and F. J. Castander Institut d’Estudis Espacials De Catalunya/CSIC, Gran Capit`a2-4, E-08034 Barcelona, Spain [email protected] ABSTRACT 1Present address: Natural Sciences Department, Castleton State College, Castleton, VT 05735 2Bolton Fellow & NSF MPS Distinguished International Postdoctoral Research Fellow –2– We present single-dish H I spectra obtained with the Green Bank Telescope, along with optical photometric properties from the Sloan Digital Sky Survey, of 20 nearby (D . 70 Mpc) Luminous Compact Blue Galaxies (LCBGs). These ∼L⋆, blue, high surface brightness, starbursting galaxies were selected with the same criteria used to define LCBGs at higher redshifts. We find these galaxies 8 9 −1 are gas-rich, with MHI ranging from 5×10 to 8×10 M⊙, and MHI LB ranging −1 from 0.2 to 2 M⊙ L⊙ , consistent with a variety of morphological types of galax- ies. We find the dynamical masses (measured within R25) span a wide range, 9 11 from 3×10 to 1×10 M⊙.
    [Show full text]
  • Sirius Astronomer) Or Editor Don Saito, [email protected]
    April 2015 Free to members, subscriptions $12 for 12 issues Volume 42, Number 4 NASA’s Dawn spacecraft arrived at dwarf planet Ceres on March 6, revealing the surface of the larg- est unexplored body in the inner Solar System for the first time. These images were taken from 40,000 kilometers (25,000 miles) from Ceres on February 25th. Over the course of the next year we will learn much more about this fascinating and important member of our solar system! (Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA) OCA CLUB MEETING STAR PARTIES COMING UP The free and open club meeng will The Black Star Canyon site will open on The next session of the Beginners be held April 10 at 7:30 PM in the Ir‐ April 11. The Anza site will be open on April Class will be held at the Heritage Mu‐ vine Lecture Hall of the Hashinger Sci‐ 18 Members are encouraged to check the seum of Orange County at 3101 West ence Center at Chapman University in website calendar for the latest updates on Harvard Street in Santa Ana on April Orange. This month’s speaker is Dr. star pares and other events. 3. The following class will be held Brendan Bowler of Caltech, who will May 1. discuss Imaging Extrasolar Planets. Please check the website calendar for the outreach events this month! Volunteers are GOTO SIG: TBA NEXT MEETINGS: May 8, June 12 always welcome! Astro‐Imagers SIG: Apr. 14, May 12 Remote Telescopes: TBA You are also reminded to check the web Astrophysics SIG: Apr.
    [Show full text]
  • A Blind HI Survey in the Canes Venatici Region
    Mon. Not. R. Astron. Soc. 400, 743–765 (2009) doi:10.1111/j.1365-2966.2009.14662.x A blind H I survey in the Canes Venatici region K. Kovac,ˇ 1,2 T. A. Oosterloo1,3 and J. M. van der Hulst1 1Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700 AV Groningen, the Netherlands 2Institute of Astronomy, ETH Zurich, 8093 Zurich, Switzerland 3Netherlands Foundation for Research in Astronomy, Postbus 2, 7990 AA Dwingeloo, the Netherlands Accepted 2009 February 18. Received 2009 February 2; in original form 2008 June 23 ABSTRACT We have carried out a blind H I survey using the Westerbork Synthesis Radio Telescope to make 6 8 an inventory of objects with small H I masses (between 10 and 10 M) and to constrain the low-mass end of the H I mass function. The survey has been conducted in a part of the volume containing the nearby Canes Venatici groups of galaxies. The surveyed region covers an area on the sky of about 86 deg2 and a range in velocity from about −450 to about 1330 km s−1. We find 70 sources in the survey by applying an automated searching algorithm. Two of the detections have not been catalogued previously, but they can be assigned an optical counterpart, based on visual inspection of the second-generation Digital Sky Survey images. Only one of the H I detections is without an optical counterpart. This object is detected in the vicinity of NGC 4822, and it has been already detected in previous H I studies. 19 of the objects have been detected for the first time in the 21-cm emission line in this survey.
    [Show full text]
  • Magellanic Type Galaxies Throughout the Universe Eric M
    The Magellanic System: Stars, Gas, and Galaxies Proceedings IAU Symposium No. 256, 2008 c 2009 International Astronomical Union Jacco Th. van Loon & Joana M. Oliveira, eds. doi:10.1017/S1743921308028871 Magellanic type galaxies throughout the Universe Eric M. Wilcots Department of Astronomy, University of Wisconsin-Madison, 475 N. Charter St., Madison, WI 53706 USA email: [email protected] Abstract. The Magellanic Clouds are often characterized as “irregular” galaxies, a term that implies an overall lack of organized structure. While this may be a fitting description of the Small Cloud, the Large Magellanic Cloud, contrary to popular opinion, should not be considered an irregular galaxy. It is characterized by a distinctive morphology of having an offset stellar bar and single spiral arm. Such morphology is relatively common in galaxies of similar mass throughout the local Universe, although explaining the origin of these features has proven challenging. Through a number of recent studies we are beginning to get a better grasp on what it means to be a Magellanic spiral. One key result of these works is that we now recognize that the most unique aspect of the Magellanic Clouds is not their structure, but, rather, their proximity to a larger spiral such as the Milky Way. Keywords. galaxies: dwarf, galaxies: evolution, galaxies: interactions, Magellanic Clouds, galax- ies: structure 1. Introduction While the Small Magellanic Cloud can properly be thought of as an irregular galaxy, the Large Magellanic Cloud shares a number of key morphological properties with a population of galaxies classified as Barred Magellanic Spirals (SBm). These properties include a stellar bar, the center of which may or may not be coincident with the dynamical center of the galaxy, a single, looping spiral arm, and often a large star-forming complex at one end of the bar.
    [Show full text]
  • NRAO Newsletter
    NRAONRAO NewsletterNewsletter The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. July 2002 www.nrao.edu/news/newsletters Number 92 DIRECTOR’S OFFICE California at Berkeley as a Miller Fellow. Two years later, he returned to Caltech where he held various research and teaching positions until 1986. Fred K.Y. Lo to Become NRAO In 1986, Lo accepted the position of Professor of Director Astronomy at the University of Illinois at Urbana- Champaign, and served as the chairman of that university's Associated Universities, astronomy department from 1995 to 1997. Lo accepted his Inc. (AUI), the not-for-profit current position at the Academia Sinica in 1997. He also corporation that operates accepted the post of Professor of Physics at the National the National Radio Astronomy Taiwan University in 1998. Observatory (NRAO) under Lo is an accomplished radio astronomer with very wide a cooperative agreement research interests. His studies range from star formation in with the National Science different environments such as dwarf galaxies, starbursts in Foundation, announces the nearby and very distant galaxies, to the determination of the appointment of Fred K.Y. Lo structure of Sagittarius A - the compact radio source at the as the director of the NRAO, center of the Milky Way Galaxy. He has been intimately effective September 1, 2002. involved in the construction and scientific use of all the mil- Lo is currently a Distinguished Research Fellow and the limeter-wave and sub-millimeter-wave interferometer arrays Director of the Institute of Astronomy and Astrophysics of in the United States, and he made the first millimeter-wave the Academia Sinica, located in Taipei.
    [Show full text]
  • A Blind HI Survey in the Canes Venatici Region
    Research Collection Journal Article A blind HI survey in the Canes Venatici region Author(s): Kovač, K.; Oosterloo, T. A.; Hulst, J. M. van der Publication Date: 2009 Permanent Link: https://doi.org/10.3929/ethz-b-000016701 Originally published in: Monthly Notices of the Royal Astronomical Society 400(2), http://doi.org/10.1111/ j.1365-2966.2009.14662.x Rights / License: In Copyright - Non-Commercial Use Permitted This page was generated automatically upon download from the ETH Zurich Research Collection. For more information please consult the Terms of use. ETH Library Mon. Not. R. Astron. Soc. 400, 743–765 (2009) doi:10.1111/j.1365-2966.2009.14662.x A blind H I survey in the Canes Venatici region K. Kovac,ˇ 1,2 T. A. Oosterloo1,3 and J. M. van der Hulst1 1Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700 AV Groningen, the Netherlands 2Institute of Astronomy, ETH Zurich, 8093 Zurich, Switzerland 3Netherlands Foundation for Research in Astronomy, Postbus 2, 7990 AA Dwingeloo, the Netherlands Accepted 2009 February 18. Received 2009 February 2; in original form 2008 June 23 ABSTRACT We have carried out a blind H I survey using the Westerbork Synthesis Radio Telescope to make 6 8 an inventory of objects with small H I masses (between 10 and 10 M) and to constrain the low-mass end of the H I mass function. The survey has been conducted in a part of the volume containing the nearby Canes Venatici groups of galaxies. The surveyed region covers an area on the sky of about 86 deg2 and a range in velocity from about −450 to about 1330 km s−1.
    [Show full text]
  • Scuola Internazionale Superiore Di Studi Avanzati - Trieste
    Scuola Internazionale Superiore di Studi Avanzati - Trieste Scuola Internazionale Superiore di Studi Avanzati Area of Physics Ph.D. in Astrophysics The nature of Dark Matter from properties of galaxies Advisor: Candidate: Prof. P. Salucci E. V. Karukes Thesis submitted in partial fulfillment of the requirements for the degree of Doctor Philosophiae Academic Year 2015/2016 SISSA - Via Bonomea 265 - 34136 TRIESTE - ITALY Acknowledgements I would like to express my special appreciation and thanks to my advisor Paolo Salucci. I appreciate all his contributions of time, ideas and discussions during these 3 years of my PhD. His advices on both research as well as on my career have been invaluable. I am thankful also to SISSA for useful lectures and to all professors of the Astrophysical sector, in particular to Alessandro Bressan, Luigi Danese and Andrea Lapi for fruitful discussions. I also thank all my friends and colleagues at SISSA Alessio, Mauro, Elena, Guillaume, Bruno, Xiao, Federico, Marco, Andrei and Lasma, who made more enjoyable the long working days and the short weekends. Then, I would like to thank Gor, Elias and Francesca for their strong and tasty coffee, that many times helped me to be productive until late. A special thank goes to my two supportive officemates Claudia and Serena for the infinite discussions about everything. I cannot forget about my friends from Rostov Polina, Roma, Vanya, Ilya and many others for all the enjoyable time we had spend together and I hope we will spend in the future. A special acknowledgement goes to my best mate of many years Nastya with whom we should write a book about all our adventures together.
    [Show full text]
  • TABLE 1 Explanation of CVRHS Symbols A
    TABLE 1 Explanation of CVRHS Symbols a Symbol Description 1 2 General Terms ETG An early-type galaxy, collectively referring to a galaxy in the range of types E to Sa ITG An intermediate-type galaxy, taken to be in the range Sab to Sbc LTG A late-type galaxy, collectively referring to a galaxy in the range of types Sc to Im ETS An early-type spiral, taken to be in the range S0/a to Sa ITS An intermediate-type spiral, taken to be in the range Sab to Sbc LTS A late-type spiral, taken to be in the range Sc to Scd XLTS An extreme late-type spiral, taken to be in the range Sd to Sm classical bulge A galaxy bulge that likely formed from early mergers of smaller galaxies (Kormendy & Kennicutt 2004; Athanassoula 2005) pseudobulge A galaxy bulge made of disk material that has secularly collected into the central regions of a barred galaxy (Kormendy 2012) PDG A pure disk galaxy, a galaxy lacking a classical bulge and often also lacking a pseudobulge Stage stage The characteristic of galaxy morphology that recognizes development of structure, the widespread distribution of star formation, and the relative importance of a bulge component along a sequence that correlates well with basic characteristics such as integrated color, average surface brightness, and HI mass-to-blue luminosity ratio Elliptical Galaxies E galaxy A galaxy having a smoothly declining brightness distribution with little or no evidence of a disk component and no inflections (such as lenses) in the luminosity distribution (examples: NGC 1052, 3193, 4472) En An elliptical galaxy
    [Show full text]
  • 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.
    [Show full text]
  • The Large Magellanic Cloud Stellar Content with SMASH: I. Assessing the Stability of the Magellanic Spiral Arms
    Astronomy & Astrophysics manuscript no. 38392corr c ESO 2020 June 22, 2020 Letter to the Editor The Large Magellanic Cloud stellar content with SMASH: I. Assessing the stability of the Magellanic spiral arms T. Ruiz-Lara1; 2, C. Gallart1; 2, M. Monelli1; 2, D. Nidever3; 4, A. Dorta1; 2, Y. Choi3; 5, K. Olsen4, G. Besla6, E.J. Bernard7, S. Cassisi8; 9, P. Massana10, N.E.D. Noël10, I. Pérez11; 12, V. Rusakov13, M.-R. L. Cioni14, S. R. Majewski15, R.P. van der Marel5; 16, D. Martínez-Delgado17, A. Monachesi18; 19, L. Monteagudo20; 1; 2, R.R. Muñoz21, G.S. Stringfellow22, F. Surot1; 2, A. K. Vivas23, A.R. Walker23, and D. Zaritsky5 1 Instituto de Astrofísica de Canarias, Calle Vía Láctea s/n, E-38205 La Laguna, Tenerife, Spain e-mail: [email protected] 2 Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain 3 Department of Physics, Montana State University, P.O. Box 173840, Bozeman, MT 59717-3840 4 NSF’s National Optical-Infrared Astronomy Research Laboratory, 950 North Cherry Ave, Tucson, AZ 85719 5 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 6 Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA 7 Université Côte d’Azur, OCA, CNRS, Lagrange, France 8 INAF – Astronomical Observatory of Abruzzo, via M. Maggini, sn, 64100 Teramo, Italy 9 INFN, Sezione di Pisa, Largo Pontecorvo 3, 56127 Pisa, Italy 10 Department of Physics, University of Surrey, Guildford, GU2 7XH, UK 11 Departamento de Física Teórica y del Cosmos, Universidad de
    [Show full text]