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THE 1000 BRIGHTEST HIPASS GALAXIES: H I PROPERTIES B
The Astronomical Journal, 128:16–46, 2004 July A # 2004. The American Astronomical Society. All rights reserved. Printed in U.S.A. THE 1000 BRIGHTEST HIPASS GALAXIES: H i PROPERTIES B. S. Koribalski,1 L. Staveley-Smith,1 V. A. Kilborn,1, 2 S. D. Ryder,3 R. C. Kraan-Korteweg,4 E. V. Ryan-Weber,1, 5 R. D. Ekers,1 H. Jerjen,6 P. A. Henning,7 M. E. Putman,8 M. A. Zwaan,5, 9 W. J. G. de Blok,1,10 M. R. Calabretta,1 M. J. Disney,10 R. F. Minchin,10 R. Bhathal,11 P. J. Boyce,10 M. J. Drinkwater,12 K. C. Freeman,6 B. K. Gibson,2 A. J. Green,13 R. F. Haynes,1 S. Juraszek,13 M. J. Kesteven,1 P. M. Knezek,14 S. Mader,1 M. Marquarding,1 M. Meyer,5 J. R. Mould,15 T. Oosterloo,16 J. O’Brien,1,6 R. M. Price,7 E. M. Sadler,13 A. Schro¨der,17 I. M. Stewart,17 F. Stootman,11 M. Waugh,1, 5 B. E. Warren,1, 6 R. L. Webster,5 and A. E. Wright1 Received 2002 October 30; accepted 2004 April 7 ABSTRACT We present the HIPASS Bright Galaxy Catalog (BGC), which contains the 1000 H i brightest galaxies in the southern sky as obtained from the H i Parkes All-Sky Survey (HIPASS). The selection of the brightest sources is basedontheirHi peak flux density (Speak k116 mJy) as measured from the spatially integrated HIPASS spectrum. 7 ; 10 The derived H i masses range from 10 to 4 10 M . -
October 2017 BRAS Newsletter
October 2017 Issue Next Meeting: Monday, October 9th at 7PM at HRPO nd (2 Mondays, Highland Road Park Observatory) October Program: BRAS President John Nagle will. reveal how he researches and puts together his Observing Notes column for our newsletter each. month. What's In This Issue? HRPO’s Great American Eclipse Event Summary (Page 2) President’s Message Secretary's Summary Outreach Report - FAE Light Pollution Committee Report Recent Forum Entries 20/20 Vision Campaign Messages from the HRPO Spooky Spectrum Observe The Moon Night Natural Sky Conference HRPO 20th Anniversary Observing Notes – Phoenix & Mythology Like this newsletter? See past issues back to 2009 at http://brastro.org/newsletters.html Newsletter of the Baton Rouge Astronomical Society October 2017 President’s Message The first Sidewalk Astronomy of the season was a success. We had a good time, and About 100 people (adult and children) attended. Ben Toman live streamed on the BRAS Facebook page. See his description in this newsletter. A copy of the proposed, revised By-Laws should be in your mail soon. Read through them, and any proposed changes need to be communicated to me before the November meeting. Wally Pursell (who wrote the original and changed by-laws) and I worked last year on getting the By-Laws updated to the current BRAS policies, and we hope the revised By-Laws will need no revisions for a long time. We need more Globe at Night observations – we are behind in the observations compared to last year at this time. We also need observations of variable stars to help in a school project by a new BRAS member, Shreya. -
A Paper for the Society for Astronomical Sciences
Three Years of Mira Variable Photometry: What Has Been Learned? Dale E. Mais Palomar Community College [email protected] David Richards Aberdeen & District Astronomical Society david@richwe b.f9.co.uk & Robert E. Stencel Dept. Physics & Astronomy University of Denver [email protected] Abstract The subject of micro-variability among Mira stars has received increased attention since DeLaverny et al. (1998) reported short-term brightness variations in 15 percent of the 250 Mira or Long Period Variable stars surveyed using the broadband 340 to 890 nm “Hp” filter on the HIPPARCOS satellite. The abrupt variations reported ranged 0.2 to 1.1 magnitudes, on time-scales between 2 to 100 hours, with a preponderance found nearer Mira minimum light phases. However, the HIPPARCOS sampling frequency was extremely sparse and required confirmation because of potentially important atmospheric dynamics and dust-formation physics that could be revealed. We report on Mira light curve sub-structure based on new CCD V and R band data, augmenting the known light curves of Hipparcos-selected long period variables [LPVs], and interpret same in terms of [1] interior structure, [2] atmospheric structure change, and/or [3] formation of circumstellar [CS] structure. We propose that the alleged micro-variability among Miras is largely undersampled, transient overtone pulsation structure in the light curves. © 2005 Society for Astronomical Science. 1. Introduction detected with HIPPARCOS, with no similar variations found for S and C-type Miras. These From European Space Agency's High Precision short-term variations were mostly detected when the Parallax Collecting Satellite, HIPPARCOS (ESA, star was fainter than Hp = 10 magnitude including 1997) mission data, deLaverny et al. -
Annual Report 1972
I I ANNUAL REPORT 1972 EUROPEAN SOUTHERN OBSERVATORY ANNUAL REPORT 1972 presented to the Council by the Director-General, Prof. Dr. A. Blaauw, in accordance with article VI, 1 (a) of the ESO Convention Organisation Europeenne pour des Recherches Astronomiques dans 1'Hkmisphtre Austral EUROPEAN SOUTHERN OBSERVATORY Frontispiece: The European Southern Observatory on La Silla mountain. In the foreground the "old camp" of small wooden cabins dating from the first period of settlement on La Silln and now gradually being replaced by more comfortable lodgings. The large dome in the centre contains the Schmidt Telescope. In the background, from left to right, the domes of the Double Astrograph, the Photo- metric (I m) Telescope, the Spectroscopic (1.>2 m) Telescope, and the 50 cm ESO and Copen- hagen Telescopes. In the far rear at right a glimpse of the Hostel and of some of the dormitories. Between the Schmidt Telescope Building and the Double Astrograph the provisional mechanical workshop building. (Viewed from the south east, from a hill between thc existing telescope park and the site for the 3.6 m Telescope.) TABLE OF CONTENTS INTRODUCTION General Developments and Special Events ........................... 5 RESEARCH ACTIVITIES Visiting Astronomers ........................................ 9 Statistics of Telescope Use .................................... 9 Research by Visiting Astronomers .............................. 14 Research by ESO Staff ...................................... 31 Joint Research with Universidad de Chile ...................... -
A Review on Substellar Objects Below the Deuterium Burning Mass Limit: Planets, Brown Dwarfs Or What?
geosciences Review A Review on Substellar Objects below the Deuterium Burning Mass Limit: Planets, Brown Dwarfs or What? José A. Caballero Centro de Astrobiología (CSIC-INTA), ESAC, Camino Bajo del Castillo s/n, E-28692 Villanueva de la Cañada, Madrid, Spain; [email protected] Received: 23 August 2018; Accepted: 10 September 2018; Published: 28 September 2018 Abstract: “Free-floating, non-deuterium-burning, substellar objects” are isolated bodies of a few Jupiter masses found in very young open clusters and associations, nearby young moving groups, and in the immediate vicinity of the Sun. They are neither brown dwarfs nor planets. In this paper, their nomenclature, history of discovery, sites of detection, formation mechanisms, and future directions of research are reviewed. Most free-floating, non-deuterium-burning, substellar objects share the same formation mechanism as low-mass stars and brown dwarfs, but there are still a few caveats, such as the value of the opacity mass limit, the minimum mass at which an isolated body can form via turbulent fragmentation from a cloud. The least massive free-floating substellar objects found to date have masses of about 0.004 Msol, but current and future surveys should aim at breaking this record. For that, we may need LSST, Euclid and WFIRST. Keywords: planetary systems; stars: brown dwarfs; stars: low mass; galaxy: solar neighborhood; galaxy: open clusters and associations 1. Introduction I can’t answer why (I’m not a gangstar) But I can tell you how (I’m not a flam star) We were born upside-down (I’m a star’s star) Born the wrong way ’round (I’m not a white star) I’m a blackstar, I’m not a gangstar I’m a blackstar, I’m a blackstar I’m not a pornstar, I’m not a wandering star I’m a blackstar, I’m a blackstar Blackstar, F (2016), David Bowie The tenth star of George van Biesbroeck’s catalogue of high, common, proper motion companions, vB 10, was from the end of the Second World War to the early 1980s, and had an entry on the least massive star known [1–3]. -
An HI Imaging Survey of Asymptotic Giant Branch Stars
Accepted to AJ Preprint typeset using LATEX style emulateapj v. 12/16/11 AN H i IMAGING SURVEY OF ASYMPTOTIC GIANT BRANCH STARS L. D. Matthews1, T. Le Bertre2, E. Gerard´ 3, M. C. Johnson4 Accepted to AJ ABSTRACT We present an imaging study of a sample of eight asymptotic giant branch (AGB) stars in the H i 21-cm line. Using observations from the Very Large Array, we have unambiguously detected H i emission associated with the extended circumstellar envelopes of six of the targets. The detected H i masses range from MHI ≈ 0.015 − 0.055M⊙. The H i morphologies and kinematics are diverse, but in all cases appear to be significantly influenced by the interaction between the circumstellar envelope and the surrounding medium. Four stars (RX Lep, Y UMa, Y CVn, and V1942 Sgr) are surrounded by detached H i shells ranging from 0.36 to 0.76 pc across. We interpret these shells as resulting from material entrained in a stellar outflow being abruptly slowed at a termination shock where it meets the local medium. RX Lep and TX Psc, two stars with moderately high space velocities −1 (Vspace > 56km s ), exhibit extended gaseous wakes (∼0.3 and 0.6 pc in the plane of the sky), trailing their motion through space. The other detected star, R Peg, displays a peculiar “horseshoe-shaped” H i morphology with emission extended on scales up to ∼1.7 pc; in this case, the circumstellar debris may have been distorted by transverse flows in the local interstellar medium. We briefly discuss our new results in the context of the entire sample of evolved stars that has been imaged in H i to date. -
Dust and CO Emission Towards the Centers of Normal Galaxies, Starburst Galaxies and Active Galactic Nuclei , I
A&A 462, 575–579 (2007) Astronomy DOI: 10.1051/0004-6361:20047017 & c ESO 2007 Astrophysics Dust and CO emission towards the centers of normal galaxies, starburst galaxies and active galactic nuclei, I. New data and updated catalogue M. Albrecht1,E.Krügel2, and R. Chini3 1 Instituto de Astronomía, Universidad Católica del Norte, Avenida Angamos 0610, Antofagasta, Chile e-mail: [email protected] 2 Max-Planck-Institut für Radioastronomie (MPIfR), Auf dem Hügel 69, 53121 Bonn, Germany 3 Astronomisches Institut der Ruhr-Universität Bochum (AIRUB), Universitätsstr. 150 NA7, 44780 Bochum, Germany Received 6 January 2004 / Accepted 27 October 2006 ABSTRACT Aims. The amount of interstellar matter in a galaxy determines its evolution, star formation rate and the activity phenomena in the nucleus. We therefore aimed at obtaining a data base of the 12CO line and thermal dust emission within equal beamsizes for galaxies in a variety of activity stages. Methods. We have conducted a search for the 12CO (1–0) and (2–1) transitions and the continuum emission at 1300 µmtowardsthe centers of 88 galaxies using the IRAM 30 m telescope (MRT) and the Swedish ESO Submillimeter Telescope (SEST). The galaxies > are selected to be bright in the far infrared (S 100 µm ∼ 9 Jy) and optically fairly compact (D25 ≤ 180 ). We have applied optical spectroscopy and IRAS colours to group the galaxies of the entire sample according to their stage of activity into three sub-samples: normal, starburst and active galactic nuclei (AGN). The continuum emission has been corrected for line contamination and synchrotron contribution to retrieve the thermal dust emission. -
7.5 X 11.5.Threelines.P65
Cambridge University Press 978-0-521-19267-5 - Observing and Cataloguing Nebulae and Star Clusters: From Herschel to Dreyer’s New General Catalogue Wolfgang Steinicke Index More information Name index The dates of birth and death, if available, for all 545 people (astronomers, telescope makers etc.) listed here are given. The data are mainly taken from the standard work Biographischer Index der Astronomie (Dick, Brüggenthies 2005). Some information has been added by the author (this especially concerns living twentieth-century astronomers). Members of the families of Dreyer, Lord Rosse and other astronomers (as mentioned in the text) are not listed. For obituaries see the references; compare also the compilations presented by Newcomb–Engelmann (Kempf 1911), Mädler (1873), Bode (1813) and Rudolf Wolf (1890). Markings: bold = portrait; underline = short biography. Abbe, Cleveland (1838–1916), 222–23, As-Sufi, Abd-al-Rahman (903–986), 164, 183, 229, 256, 271, 295, 338–42, 466 15–16, 167, 441–42, 446, 449–50, 455, 344, 346, 348, 360, 364, 367, 369, 393, Abell, George Ogden (1927–1983), 47, 475, 516 395, 395, 396–404, 406, 410, 415, 248 Austin, Edward P. (1843–1906), 6, 82, 423–24, 436, 441, 446, 448, 450, 455, Abbott, Francis Preserved (1799–1883), 335, 337, 446, 450 458–59, 461–63, 470, 477, 481, 483, 517–19 Auwers, Georg Friedrich Julius Arthur v. 505–11, 513–14, 517, 520, 526, 533, Abney, William (1843–1920), 360 (1838–1915), 7, 10, 12, 14–15, 26–27, 540–42, 548–61 Adams, John Couch (1819–1892), 122, 47, 50–51, 61, 65, 68–69, 88, 92–93, -
A Moving Cluster Distance to the Exoplanet 2M1207 B in the TW Hya
accepted to Astrophysical Journal, 18 July 2005 A Moving Cluster Distance to the Exoplanet 2M1207 B in the TW Hya Association Eric E. Mamajek1 Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS-42, Cambridge, MA 02138 [email protected] ABSTRACT A candidate extrasolar planet companion to the young brown dwarf 2MASSW J1207334-393254 (2M1207) was recently discovered by Chauvin et al. They find that 2M1207 B’s temperature and luminosity are consistent with being a young, ∼5 MJup planet. The 2M1207 system is purported to be a member of the TW Hya association (TWA), and situated ∼70 pc away. Using a revised space mo- tion vector for TWA, and improved proper motion for 2M1207, I use the moving cluster method to estimate the distance to the 2M1207 system and other TWA members. The derived distance for 2M1207 (53 ± 6 pc) forces the brown dwarf and planet to be half as luminous as previously thought. The inferred masses for 2M 1207 A and B decrease to ∼21 MJup and ∼3-4MJup, respectively, with the mass of B being well below the observed tip of the planetary mass function and the theoretical deuterium-burning limit. After removing probable Lower arXiv:astro-ph/0507416v1 18 Jul 2005 Centaurus-Crux (LCC) members from the TWA sample, as well as the prob- able non-member TWA 22, the remaining TWA members are found to have distances of 49 ± 3 (s.e.m.) ± 12(1σ) pc, and an internal 1D velocity dispersion of +0.3 −1 0.8−0.2 km s . There is weak evidence that the TWA is expanding, and the data are consistent with a lower limit on the expansion age of 10 Myr (95% confidence). -
![Arxiv:1803.01321V1 [Astro-Ph.GA] 4 Mar 2018 H Adsget Rw” Uhrte Ogand Calling Long Feature, Rather Such This “Rows”](https://docslib.b-cdn.net/cover/9532/arxiv-1803-01321v1-astro-ph-ga-4-mar-2018-h-adsget-rw-uhrte-ogand-calling-long-feature-rather-such-this-rows-1569532.webp)
Arxiv:1803.01321V1 [Astro-Ph.GA] 4 Mar 2018 H Adsget Rw” Uhrte Ogand Calling Long Feature, Rather Such This “Rows”
Butenko M.A., Khoperskov A.V. Galaxies with https://doi.org/10.1134/S1990341317030130 “Rows”: A New Catalog // Astrophysical Bul- letin, 2017, vol.72, No.3, 232–250 GALAXIES WITH “ROWS”: A NEW CATALOG M. A. Butenko1, * and A. V. Khoperskov1, ** 1Volgograd State University, Volgograd, 400062 Russia Galaxies with “rows” in Vorontsov-Velyaminov’s terminology stand out among the variety of spiral galactic patterns. A characteristic feature of such objects is the sequence of straight- line segments that forms the spiral arm. In 2001 A. Chernin and co-authors published a catalog of such galaxies which includes 204 objects from the Palomar Atlas. In this paper, we supplement the catalog with 276 objects based on an analysis of all the galaxies from the New General Catalogue and Index Catalogue. The total number of NGC and IC galaxies with rows is 406, including the objects of Chernin et al. (2001). The use of more recent galaxy images allowed us to detect more “rows” on average, compared with the catalog of Chernin et al. When comparing the principal galaxy properties we found no significant differences between galaxies with rows and all S-typeNGC/IC galaxies.We discuss twomechanisms for the formation of polygonal structures based on numerical gas-dynamic and collisionless N- body calculations, which demonstrate that a spiral pattern with rows is a transient stage in the evolution of galaxies and a system with a powerful spiral structure can pass through this stage. The hypothesis of A. Chernin et al. (2001) that the occurrence frequency of interacting galaxies is twice higher among galaxies with rows is not confirmed for the combined set of 480 galaxies. -
Bar Strength and Star Formation Activity in Late-Type Barred Galaxies
A&A manuscript no. (will be inserted by hand later) ASTRONOMY AND Your thesaurus codes are: ASTROPHYSICS 4(11.01.1; 11.05.2; 11.19.3; 13.09.1) 30.9.2018 Bar strength and star formation activity in late-type barred galaxies L. Martinet and D. Friedli ⋆ Observatoire de Gen`eve, CH-1290 Sauverny, Switzerland E-mail: [email protected] Received 23 September 1996 / Accepted 24 December 1996 Abstract. With the prime aim of better probing and un- the past. For instance, the role of gas, the effects of inter- derstanding the intimate link between star formation ac- actions not only between galaxies but also between vari- tivity and the presence of bars, a representative sample of ous components of a given system, the necessity to fully 32 non-interacting late-type galaxies with well-determined take into account 3D structures, the interplay between bar properties has been selected. We show that all the star formation and dynamical mechanisms, etc. In fact, galaxies displaying the highest current star forming ac- discs are the seat of evolutionary processes on timescales tivity have both strong and long bars. Conversely not all of the order of the Hubble time or less (see the reviews by strong and long bars are intensively creating stars. Except Kormendy 1982; Martinet 1995; Pfenniger 1996; see also for two cases, strong bars are in fact long as well. Numer- e.g. Pfenniger & Norman 1990; Friedli & Benz 1993, 1995; ical simulations allow to understand these observational Courteau et al. 1996; Norman et al. 1996). In particular, facts as well as the connection between bar axis ratio, bars do play a decisive role in such processes. -
Doppler Imaging of the Helium-Variable Star a Centauri*
A&A 520, A44 (2010) Astronomy DOI: 10.1051/0004-6361/201014157 & c ESO 2010 Astrophysics Doppler imaging of the helium-variable star a Centauri D. A. Bohlender1,J.B.Rice2, and P. Hechler2 1 National Research Council of Canada, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC, V9E 2E7, Canada e-mail: [email protected] 2 Department of Physics and Astronomy, Brandon University, Brandon, MB R7A 6A9, Canada e-mail: [email protected] Received 29 January 2010 / Accepted 14 June 2010 ABSTRACT Aims. The helium-peculiar star a Cen exhibits interesting line profile variations of elements such as iron, nitrogen and oxygen in addition to its well-known extreme helium variability. The objective of this paper is to use new high signal-to-noise, high-resolution spectra to perform a quantitative measurement of the helium, iron, nitrogen and oxygen abundances of the star and determine the relation of the concentrations of the heavier elements on the surface of the star to the helium concentration and perhaps to the magnetic field orientation. Methods. Doppler images have been created for the elements helium, iron, nitrogen and oxygen using the programs described in earlier papers by Rice and others. An alternative surface abundance mapping code has been used to model the helium line variations after our Doppler imaging of certain individual helium lines produced mediocre results. Results. Doppler imaging of the helium abundance of a Cen confirms the long-known existence of helium-rich and helium-poor hemispheres on the star and we measure a difference of more than two orders of magnitude in helium abundance from one side of the star to the other.