DOCSLIB.ORG

Cold Dust and Molecular Gas Towards the Centers of Magellanic Type Galaxies and Irregulars,

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Cold Dust and Molecular Gas Towards the Centers of Magellanic Type Galaxies and Irregulars�, A&A 414, 141–153 (2004) Astronomy DOI: 10.1051/0004-6361:20031634 & c ESO 2004 Astrophysics Cold dust and molecular gas towards the centers of Magellanic type galaxies and irregulars, I. The data M. Albrecht1,R.Chini1,E.Kr¨ugel2,S.A.H.M¨uller1,andR.Lemke1 1 Astronomisches Institut der Ruhr-Universit¨at Bochum, Universit¨atsstr. 150, 44780 Bochum, Germany e-mail: [email protected] 2 Max Planck Institut f¨ur Radioastronomie Bonn, Auf dem H¨ugel 69, 53121 Bonn, Germany Received 29 July 2003 / Accepted 16 October 2003 Abstract. We present 1300 µm continuum emission measurements and observations of the 12CO (1–0) and (2–1) transition towards the centers of 64 Magellanic type galaxies (Sdm/Sm) and irregulars (Im/I0/Irr). The sources are selected to have 12 IRAS flux densities S 100 µm ≥ 1000 mJy and optical diameters mainly below 180 . We were able to detect CO towards 41 and the continuum emission towards 28 galaxies. In addition, we obtained the corresponding data for a set of 6 complementary galaxies of different morphological type. Key words. galaxies: interstellar matter – galaxies: abundances – galaxies: Magellanic type – radio lines: galaxies – radio continuum: galaxies 1. Introduction comparison of the two independent tracers of the amount of molecular gas. Among the various constituents of the interstellar matter (ISM) While similar studies have been conducted for galaxies of the amount of dust and molecular gas are decisive quantities Hubble type S0 to Sd (Chini et al. 1996; Kr¨ugel et al. 1988a, for our understanding of galaxy evolution, chemistry and star 1988b, 1990), no systematic approach to observe dust as well formation processes. As H2 lacks a permanent electric dipole as molecular gas towards Magellanic type dwarfs with the same moment and its emission arises only from hot or warm gas, beam size has been made so far. The presented measurements absorption measurements against strong far-ultraviolet back- will allow a comparison with galaxies of earlier Hubble type as ground sources or indirect methods are used to estimate the regards their properties derived from mm observations. mass of the cold molecular component of the ISM. The most In the following we describe the observational setups and widely applied indirect methods consider the CO line emission the data reduction. We present the resulting flux densities of the or the dust mass as tracers. Dust itself is of special interest as it 1300 µm continuum emission. Furthermore, we show the ob- is strongly linked to star formation. It has the property of being tained 12CO spectra and list the corresponding line parameters. very sensitive to the ultraviolet radiation of young massive stars For a set of galaxies the 12CO lines led to independent distance and re-radiates it from infrared to mm wavelengths. A main estimates which in conjunction with data from the literature 12 goal of this study is to obtain measurements of the CO line were used to newly derive H and optical properties of the ob- µ transitions and the continuum emission at 1300 m at an iden- jects. The data will be discussed in detail elsewhere (Albrecht tical or at least similar spatial resolution. This does not only et al., in prep.). facilitate a reliable correction of the continuum emission for line contamination but – more importantly – allows a direct 2. Galaxy sample Send offprint requests to: M. Albrecht, Our galaxy sample contains 31 Magellanic type spirals e-mail: [email protected] (Sdm, Sm), 30 Magellanic irregulars (Im) and 3 irregulars Based on observations collected at ESO, La Silla, Chile and (I0, Irr) according to the classification of de Vaucouleurs IRAM, Pico Veleta, Spain. et al. (1991, hereafter RC3). The objects have been taken The full version of Figs. 3 and 4 is only available in electronic from the compilation of morphological dwarf galaxies with form at http://www.edpsciences.org known optical magnitudes, optical sizes and H fluxes by Article published by EDP Sciences and available at http://www.aanda.org or http://dx.doi.org/10.1051/0004-6361:20031634 142 M. Albrecht et al.: Dust and molecular gas in Magellanic type galaxies and irregulars. I. Table 1. The Sdm/Sm sample. Name Name RA Dec D Angular d25 S 100 µm logMH i MB Morph. Type (J2000.0) (J2000.0) Size (IRAS) [Mpc] [arcmin] [kpc] [mJy] [M][mag] (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) NGC 145 ARP 19 00:31:45.7 −05:09:10 55.0 (P) 1.8 × 1.3 28.8 6156 9.97 –20.9 SB(s)dm NGC 178 IC 39, 00:39:08.5 −14:10:17 19.3 (P) 2.0 × 1.0 11.2 2586 9.40 –18.8 SB(s)m NGC 959 UGC 2002 02:32:24.0 +35:29:42 10.1 (c) 2.3 × 1.4 6.8 2709 8.49 –17.8 Sdm: IC 292 IC 1887 03:10:12.9 +40:45:56 39.8 (H) 1.2 × 0.6 13.9 4617 9.50 –19.6 Sdm DDO 36 05:07:46.9 −16:17:37 27.0 (H) 2.3 × 1.4 18.1 1528 9.57 –19.0 SB(s)m UGCA 103 DDO 230 05:10:47.0 −31:35:50 12.8 (H) 3.0 × 2.5 11.2 1413 9.12 –17.5 SB(r)dm NGC 1879 UGCA 110 05:19:48.2 −32:08:34 16.3 (P) 2.5 × 1.7 11.9 1079 9.04 –18.1 SB(s)m UGC 4151 08:04:18.7 +77:49:00 30.7 (P) 1.4 × 1.3 12.5 2220 8.97 –19.4 Sdm: NGC 2537 UGC 4274 08:13:14.7 +45:59:26 5.9 (f) 1.7 × 1.5 2.9 4810 8.23 –16.8 SB(s)m pec NGC 2730 UGC 4743 09:02:15.9 +16:50:18 51.3 (P) 1.7 × 1.3 25.4 1996 9.67 –20.3 SBdm: NGC 3057 UGC 5404 10:05:39.1 +80:17:08 20.4 (H) 2.2 × 1.3 13.1 1397 9.06 –18.3 SB(s)dm NGC 3246 UGC 5661 10:26:41.8 +03:51:43 28.6 (H) 2.4 × 1.3 20.0 1574 9.67 –19.5 SABdm NGC 3445 UGC 6021 10:54:35.9 +56:59:24 27.3 (P) 1.6 × 1.5 12.7 2960 9.50 –19.3 SAB(s)m NGC 3659 UGC 6405 11:23:45.4 +17:49:06 17.4 (P) 2.1 × 1.1 10.6 4073 9.28 –18.7 SB(s)m? NGC 3664 UGC 6419 11:24:25.0 +03:19:34 18.4 (P) 2.0 × 1.9 10.7 1962 9.27 –18.4 SB(s)m pec NGC 3839 UGC 6700 11:43:54.3 +10:47:06 78.9 (H) 1.0 × 0.5 23.0 7169 10.24 –20.4 Sdm: NGC 3879 UGC 6752 11:46:49.8 +69:22:59 19.2 (H) 2.6 × 0.5 14.5 1030 9.24 –18.7 Sdm: NGC 3991 UGC 6933 11:57:30.4 +32:20:03 42.8 (P) 0.6 × 0.27.5<11 150 10.00 –19.9 Sm NGC 4234 UGC 7309 12:17:09.2 +03:40:59 20.0 (V) 1.3 × 1.3 7.6 4068 8.50 –18.2 (R’)SB(s)m NGC 4299 UGC 7414 12:21:40.9 +11:30:03 20.0 (V) 1.7 × 1.69.9 <8086 9.20 –18.8 SAB(s)dm: NGC 4523 UGC 7713 12:33:48.0 +15:10:05 20.0 (V) 2.0 × 1.9 11.6 1303 9.26 –17.5 SAB(s)m IC 3521 UGC 7736 12:34:39.5 +07:09:36 20.0 (V) 1.3 × 0.9 7.6 2301 8.13 –17.6 SBm pec NGC 4625 IC 3675 12:41:52.6 +41:16:26 8.3 (P) 2.2 × 1.9 5.3 3575 8.71 –16.7 SAB(rs)m pec NGC 5238 UGC 8565 13:34:42.7 +51:36:51 5.2 (d) 1.7 × 1.4 2.6 1213 7.64 –14.8 SAB(s)dm DDO 180 13:38:10.3 −09:48:05 17.3 (P) 2.3 × 1.9 11.6 2075 9.14 –18.6 SB(s)m NGC 5433 UGC 8954 14:02:36.0 +32:30:38 57.5 (H) 1.6 × 0.4 26.8 11 110 9.79 –20.4 Sdm: NGC 5486 UGC 9036 14:07:25.2 +55:06:11 18.2 (P) 1.9 × 1.2 10.1 1138 9.08 –17.7 SA(s)m: NGC 5630 UGC 9270 14:27:36.7 +41:15:27 35.6 (H) 2.2 × 0.7 22.8 3536 9.68 –19.8 Sdm: NGC 6570 UGC 11137 18:11:07.3 +14:05:35 30.7 (H) 1.8 × 1.1 16.1 6250 9.44 –20.1 SB(rs)m: NGC 7162A 22:00:35.7 −43:08:30 30.3 (H) 2.6 × 2.3 22.9 1122 9.64 –19.1 SB(s)m UGC 12082 DDO 213 22:34:10.9 +32:51:44 10.8 (H) 2.6 × 2.2 8.2 1911 8.94 –16.3 Sm Notes: (a): Clemens et al. (1999), (b): Heydari-Malayeri et al. (1990), (c): Ho et al. (1997), (d): Makarova & Karachentsev (1998), (e): Meurer et al.
Load more

Recommended publications
  • Linking Dust Emission to Fundamental Properties in Galaxies: the Low-Metallicity Picture?
    A&A 582, A121 (2015) Astronomy DOI: 10.1051/0004-6361/201526067 & c ESO 2015 Astrophysics Linking dust emission to fundamental properties in galaxies: the low-metallicity picture? A. Rémy-Ruyer1;2, S. C. Madden2, F. Galliano2, V. Lebouteiller2, M. Baes3, G. J. Bendo4, A. Boselli5, L. Ciesla6, D. Cormier7, A. Cooray8, L. Cortese9, I. De Looze3;10, V. Doublier-Pritchard11, M. Galametz12, A. P. Jones1, O. Ł. Karczewski13, N. Lu14, and L. Spinoglio15 1 Institut d’Astrophysique Spatiale, CNRS, UMR 8617, 91405 Orsay, France e-mail: [email protected]; [email protected] 2 Laboratoire AIM, CEA/IRFU/Service d’Astrophysique, Université Paris Diderot, Bât. 709, 91191 Gif-sur-Yvette, France 3 Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, 9000 Gent, Belgium 4 UK ALMA Regional Centre Node, Jodrell Bank Centre for Astrophysics, School of Physics & Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK 5 Laboratoire d’Astrophysique de Marseille – LAM, Université d’Aix-Marseille & CNRS, UMR 7326, 38 rue F. Joliot-Curie, 13388 Marseille Cedex 13, France 6 Department of Physics, University of Crete, 71003 Heraklion, Greece 7 Zentrum für Astronomie der Universität Heidelberg, Institut für Theoretische Astrophysik, Albert-Ueberle-Str. 2, 69120 Heidelberg, Germany 8 Center for Cosmology, Department of Physics and Astronomy, University of California, Irvine, CA 92697, USA 9 Centre for Astrophysics & Supercomputing, Swinburne University of Technology, Mail H30, PO Box 218, Hawthorn VIC 3122, Australia 10 Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK 11 Max-Planck für Extraterrestrische Physik, Giessenbachstr. 1, 85748 Garching-bei-München, Germany 12 European Southern Observatory, Karl-Schwarzschild-Str.
    [Show full text]
  • Astronomy 2008 Index
    Astronomy Magazine Article Title Index 10 rising stars of astronomy, 8:60–8:63 1.5 million galaxies revealed, 3:41–3:43 185 million years before the dinosaurs’ demise, did an asteroid nearly end life on Earth?, 4:34–4:39 A Aligned aurorae, 8:27 All about the Veil Nebula, 6:56–6:61 Amateur astronomy’s greatest generation, 8:68–8:71 Amateurs see fireballs from U.S. satellite kill, 7:24 Another Earth, 6:13 Another super-Earth discovered, 9:21 Antares gang, The, 7:18 Antimatter traced, 5:23 Are big-planet systems uncommon?, 10:23 Are super-sized Earths the new frontier?, 11:26–11:31 Are these space rocks from Mercury?, 11:32–11:37 Are we done yet?, 4:14 Are we looking for life in the right places?, 7:28–7:33 Ask the aliens, 3:12 Asteroid sleuths find the dino killer, 1:20 Astro-humiliation, 10:14 Astroimaging over ancient Greece, 12:64–12:69 Astronaut rescue rocket revs up, 11:22 Astronomers spy a giant particle accelerator in the sky, 5:21 Astronomers unearth a star’s death secrets, 10:18 Astronomers witness alien star flip-out, 6:27 Astronomy magazine’s first 35 years, 8:supplement Astronomy’s guide to Go-to telescopes, 10:supplement Auroral storm trigger confirmed, 11:18 B Backstage at Astronomy, 8:76–8:82 Basking in the Sun, 5:16 Biggest planet’s 5 deepest mysteries, The, 1:38–1:43 Binary pulsar test affirms relativity, 10:21 Binocular Telescope snaps first image, 6:21 Black hole sets a record, 2:20 Black holes wind up galaxy arms, 9:19 Brightest starburst galaxy discovered, 12:23 C Calling all space probes, 10:64–10:65 Calling on Cassiopeia, 11:76 Canada to launch new asteroid hunter, 11:19 Canada’s handy robot, 1:24 Cannibal next door, The, 3:38 Capture images of our local star, 4:66–4:67 Cassini confirms Titan lakes, 12:27 Cassini scopes Saturn’s two-toned moon, 1:25 Cassini “tastes” Enceladus’ plumes, 7:26 Cepheus’ fall delights, 10:85 Choose the dome that’s right for you, 5:70–5:71 Clearing the air about seeing vs.
    [Show full text]
  • 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.
    [Show full text]
  • Machine Learning for Star Cluster Identification∗ Submitted to Apj
    Draft version December 1, 2020 Typeset using LATEX default style in AASTeX63 StarcNet: Machine Learning for Star Cluster Identification∗ Gustavo Perez´ ,1 Matteo Messa ,2 Daniela Calzetti ,2 Subhransu Maji ,1 Dooseok E. Jung ,2 Angela Adamo ,3 and Mattia Siressi3 1Department of Computer Science University of Massachusetts Amherst 40 Governors Drive Amherst, MA 01003, USA 2Department of Astronomy University of Massachusetts Amherst 710 North Pleasant Street Amherst, MA 01003, USA 3Department of Astronomy, Oskar Klein Centre, Stockholm University, AlbaNova University Centre, SE-106 91 Stockholm, Sweden (Received July 1, 2020; Revised; Accepted) Submitted to ApJ ABSTRACT We present a machine learning (ML) pipeline to identify star clusters in the multi{color images of nearby galaxies, from observations obtained with the Hubble Space Telescope as part of the Treasury Project LEGUS (Legacy ExtraGalactic Ultraviolet Survey). StarcNet (STAR Cluster classification NETwork) is a multi{scale convolutional neural network (CNN) which achieves an accuracy of 68.6% (4 classes)/86.0% (2 classes: cluster/non{cluster) for star cluster classification in the images of the LEGUS galaxies, nearly matching human expert performance. We test the performance of StarcNet by applying pre{trained CNN model to galaxies not included in the training set, finding accuracies similar to the reference one. We test the effect of StarcNet predictions on the inferred cluster properties by comparing multi{color luminosity functions and mass{age plots from catalogs produced by StarcNet and by human{labeling; distributions in luminosity, color, and physical characteristics of star clusters are similar for the human and ML classified samples. There are two advantages to the ML approach: (1) reproducibility of the classifications: the ML algorithm's biases are fixed and can be measured for subsequent analysis; and (2) speed of classification: the algorithm requires minutes for tasks that humans require weeks to months to perform.
    [Show full text]
  • 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.
    [Show full text]
  • Testing the Paradigm That Ultra-Luminous X-Ray Sources As a Class Represent Accreting Intermediate-Mass Black Holes
    Testing the Paradigm that Ultra-Luminous X-ray Sources as a Class Represent Accreting Intermediate-Mass Black Holes C. T. Berghea Department of Physics, The Catholic University of America, Washington, DC 20064 [email protected] K. A. Weaver Laboratory for High Energy Astrophysics, NASA's Goddard Space Flight Center, Greenbelt, MD 20771 [email protected] E. J. M. Colbert Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 [email protected] and T. P. Roberts Department of Physics, Durham University, South Road, Durham DH1 3LE, UK [email protected] ABSTRACT To test the idea that ultraluminous X-ray sources (ULXs) in external galaxies represent a class of accreting Intermediate-Mass Black Holes (IMBHs), we have undertaken a program to identify ULXs and a lower luminosity X-ray compari- son sample with the highest quality data in the Chandra archive. We establish a general property of ULXs that the most X-ray luminous objects possess the flattest X-ray spectra (in the Chandra band pass). No prior sample studies have established the general hardening of ULX spectra with luminosity. This hard- ening occurs at the highest luminosities (absorbed luminosity ≥5×1039 erg s−1) and is in line with recent models arguing that ULXs are actually stellar-mass black holes. From spectral modeling, we show that the evidence originally taken { 2 { to mean that ULXs are IMBHs - i.e., the \simple IMBH model" - is nowhere near as compelling when a large sample of ULXs is looked at properly. During the last couple of years, XMM-Newton spectroscopy of ULXs has to some large extent begun to negate the simple IMBH model based on fewer objects.
    [Show full text]
  • Radial Star Formation Histories in Fifteen Nearby Galaxies
    RADIAL STAR FORMATION HISTORIES IN FIFTEEN NEARBY GALAXIES Daniel A. Dale1, Gillian D. Beltz-Mohrmann2, Arika A. Egan3, Alan J. Hatlestad1, Laura J. Herzog4, Andrew S. Leung5, Jacob N. McLane5, Christopher Phenicie6, Jareth S. Roberts1, Kate L. Barnes7, M´ed´eric Boquien8, Daniela Calzetti9, David O. Cook1, Henry A. Kobulnicky1, Shawn M. Staudaher1, and Liese van Zee7 ABSTRACT New deep optical and near-infrared imaging is combined with archival ultravi- olet and infrared data for fifteen nearby galaxies mapped in the Spitzer Extended Disk Galaxy Exploration Science survey. These images are particularly deep and thus excellent for studying the low surface brightness outskirts of these disk- 8 11 dominated galaxies with stellar masses ranging between 10 and 10 M⊙. The spectral energy distributions derived from this dataset are modeled to investigate the radial variations in the galaxy colors and star formation histories. Taken as a whole, the sample shows bluer and younger stars for larger radii until reversing near the optical radius, whereafter the trend is for redder and older stars for larger galacto-centric distances. These results are consistent with an inside-out disk formation scenario coupled with an old stellar outer disk population formed through radial migration and/or the cumulative history of minor mergers and ac- cretions of satellite dwarf galaxies. However, these trends are quite modest and the variation from galaxy to galaxy is substantial. Additional data for a larger sample of galaxies are needed to confirm or dismiss
    [Show full text]
  • Dwarf Galaxies
    Europeon South.rn Ob.ervotory• ESO ML.2B~/~1 ~~t.· MAIN LIBRAKY ESO Libraries ,::;,q'-:;' ..-",("• .:: 114 ML l •I ~ -." "." I_I The First ESO/ESA Workshop on the Need for Coordinated Space and Ground-based Observations - DWARF GALAXIES Geneva, 12-13 May 1980 Report Edited by M. Tarenghi and K. Kjar - iii - INTRODUCTION The Space Telescope as a joint undertaking between NASA and ESA will provide the European community of astronomers with the opportunity to be active partners in a venture that, properly planned and performed, will mean a great leap forward in the science of astronomy and cosmology ­ in our understanding of the universe. The European share, however,.of at least 15% of the observing time with this instrumentation, if spread over all the European astrono­ mers, does not give a large amount of observing time to each individual scientist. Also, only well-planned co­ ordinated ground-based observations can guarantee success in interpreting the data and, indeed, in obtaining observ­ ing time on the Space Telescope. For these reasons, care­ ful planning and cooperation between different European groups in preparing Space Telescope observing proposals would be very essential. For these reasons, ESO and ESA have initiated a series of workshops on "The Need for Coordinated Space and Ground­ based Observations", each of which will be centred on a specific subject. The present workshop is the first in this series and the subject we have chosen is "Dwarf Galaxies". It was our belief that the dwarf galaxies would be objects eminently suited for exploration with the Space Telescope, and I think this is amply confirmed in these proceedings of the workshop.
    [Show full text]
  • Physical Conditions of the Molecular Gas in Metal-Poor Galaxies? L
    A&A 606, A99 (2017) Astronomy DOI: 10.1051/0004-6361/201731000 & c ESO 2017 Astrophysics Physical conditions of the molecular gas in metal-poor galaxies? L. K. Hunt1, A. Weiß2, C. Henkel2; 3, F. Combes4, S. García-Burillo5, V. Casasola1, P. Caselli6, A. Lundgren9, R. Maiolino7, K. M. Menten2, and L. Testi1; 8 1 INAF–Osservatorio Astrofisico di Arcetri, Largo E. Fermi, 5, 50125 Firenze, Italy e-mail: [email protected] 2 Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany 3 Astronomy Department, King Abdulaziz University, PO Box 80203, Jeddah, Saudia Arabia 4 Observatoire de Paris, LERMA, Collège de France, CNRS, PSL, Sorbonne University UPMC, 75014 Paris, France 5 Observatorio Astronómico Nacional (OAN)-Observatorio de Madrid, Alfonso XII, 3, 28014 Madrid, Spain 6 Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching, Germany 7 Cavendish Laboratory, University of Cambridge, 19 J.J. Thomson Avenue, Cambridge CB3 0HE, UK 8 ESO, Karl Schwarzschild str. 2, 85748 Garching bei München, Germany 9 Vittja 64, 74793 Alunda, Sweden Received 18 April 2017 / Accepted 8 August 2017 ABSTRACT Studying the molecular component of the interstellar medium (ISM) in metal-poor galaxies has been challenging because of the faint- ness of carbon monoxide emission, the most common proxy of H2. Here we present new detections of molecular gas at low metal- licities, and assess the physical conditions in the gas through various CO transitions for 8 galaxies. For one, NGC 1140 (Z=Z ∼ 0.3), two detections of 13CO isotopologues and atomic carbon, [Ci](1–0) and an upper limit for HCN(1–0) are also reported.
    [Show full text]
  • New Type of Black Hole Detected in Massive Collision That Sent Gravitational Waves with a 'Bang'
    New type of black hole detected in massive collision that sent gravitational waves with a 'bang' By Ashley Strickland, CNN Updated 1200 GMT (2000 HKT) September 2, 2020 &lt;img alt="Galaxy NGC 4485 collided with its larger galactic neighbor NGC 4490 millions of years ago, leading to the creation of new stars seen in the right side of the image." class="media__image" src="//cdn.cnn.com/cnnnext/dam/assets/190516104725-ngc-4485-nasa-super-169.jpg"&gt; Photos: Wonders of the universe Galaxy NGC 4485 collided with its larger galactic neighbor NGC 4490 millions of years ago, leading to the creation of new stars seen in the right side of the image. Hide Caption 98 of 195 &lt;img alt="Astronomers developed a mosaic of the distant universe, called the Hubble Legacy Field, that documents 16 years of observations from the Hubble Space Telescope. The image contains 200,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the Big Bang. " class="media__image" src="//cdn.cnn.com/cnnnext/dam/assets/190502151952-0502-wonders-of-the-universe-super-169.jpg"&gt; Photos: Wonders of the universe Astronomers developed a mosaic of the distant universe, called the Hubble Legacy Field, that documents 16 years of observations from the Hubble Space Telescope. The image contains 200,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the Big Bang. Hide Caption 99 of 195 &lt;img alt="A ground-based telescope&amp;amp;#39;s view of the Large Magellanic Cloud, a neighboring galaxy of our Milky Way.
    [Show full text]
  • An Atlas of Calcium Triplet Spectra of Active Galaxies 3
    Mon. Not. R. Astron. Soc. 000, 000–000 (0000) Printed 1 December 2018 (MN LATEX style file v2.2) An atlas of Calcium triplet spectra of active galaxies A. Garcia-Rissmann1⋆, L. R. Vega1,2†, N. V. Asari1‡, R. Cid Fernandes1§, H. Schmitt3,4¶, R. M. Gonz´alez Delgado5k, T. Storchi-Bergmann6⋆⋆ 1 Depto. de F´ısica - CFM - Universidade Federal de Santa Catarina, C.P. 476, 88040-900, Florian´opolis, SC, Brazil 2 Observatorio Astron´omico de C´ordoba, Laprida 854, 5000, C´ordoba, Argentina 3 Remote Sensing Division, Code 7210, Naval Research Laboratory, 4555 Overlook Avenue, SW, Washington, DC 20375 4 Interferometric Inc., 14120 Parke Long Court, 103, Chantilly, VA20151 5 Instituto de Astrof´ısica de Andaluc´ıa (CSIC), P.O. Box 3004, 18080 Granada, Spain 6 Instituto de F´ısica, Universidade Federal do Rio Grande do Sul, C.P. 15001, 91501-970, Porto Alegre, RS, Brazil 1 December 2018 ABSTRACT We present a spectroscopic atlas of active galactic nuclei covering the region around the λλ8498, 8542, 8662 Calcium triplet (CaT). The sample comprises 78 ob- jects, divided into 43 Seyfert 2s, 26 Seyfert 1s, 3 Starburst and 6 normal galaxies. The spectra pertain to the inner ∼ 300 pc in radius, and thus sample the central kine- matics and stellar populations of active galaxies. The data are used to measure stellar velocity dispersions (σ⋆) both with cross-correlation and direct fitting methods. These measurements are found to be in good agreement with each-other and with those in previous studies for objects in common. The CaT equivalent width is also measured.
    [Show full text]
  • 042021-Aktuelles Am Sternenhimmel
    A N T A R E S NÖ AMATEURASTRONOMEN NOE VOLKSSTERNWARTE Michelbach Dorf 62 3074 MICHELBACH NOE VOLKSSTERNWARTE 3074 MICHELBACH Die VOLKSSTERNWARTE im Zentralraum Niederösterreich 02.04.1966 Luna 10 schwenkt als 1. Sonde in einen Mondorbit ein (UdSSR) 03.04.1959 Die ersten sieben Astronauten der USA werden bekanntgegeben 10.04.1970 Start Apollo 13; Nach einer Explosion kehren Jim Lovell, Jack Swigert und Fred Haise mit der Mondlandefähre als Rettungsboot zur Erde zurück 12.04.1960 Start von Transit 1B: Erster Navigationssatellit im All 12.04.1961 Vostok 1 (UdSSR) bringt den 1. Menschen ins All (Juri Gagarin!) 13.04.1862 Christian Huygens, Saturnforscher, wird geboren 18.04.1971 Start der 1. Weltraumstation Saljut 1 (UdSSR) 21.04.1971 Die erste Besatzung dockt an der ersten Raumstation Saljut 1 an (UdSSR) 22.04.1967 Wladimir Komarov stirbt als erster Kosmonaut im Weltraum (Sojus 1) 23.04.1990 Weltraumteleskop Hubble wird mit dem Shuttle Flug 31 gestartet 24.04.1962 Ariel 1, der erste internationale Satellit, wird gestartet (USA, England) AKTUELLES AM STERNENHIMMEL APRIL 2021 Die Wintersternbilder sind Objekte der westlichen Himmelshälfte; der Große Bär steht hoch im Zenit, die Frühlingssternbilder Löwe, Bärenhüter und Jungfrau mit den Galaxienhaufen können in der östlichen Himmelshälfte beobachtet werden; südlich der Jungfrau stehen Becher und Rabe, über dem Südhorizont schlänget sich die unscheinbare Wasserschlange. Mars ist am Abendhimmel in den Zwillingen auffindbar, Jupiter und Saturn werden die Planeten der zweiten Nachthälfte. INHALT Auf- und Untergangszeiten Sonne und Mond Fixsternhimmel Monatsthema – Juri Gagarin, 1. Mensch im Weltraum – 12.04.1961 Planetenlauf Sternschnuppenschwärme Vereinsabend – 09.04.2021 – ONLINE-Veranstaltung Führungstermin 16.04.2021 - ABSAGE VEREINSABEND 09.04.2021 REFERENT Doz.
    [Show full text]