Assessment of Stellar Stratification in Three Young Star Clusters in The
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Giant H II Regions in the Merging System NGC 3256: Are They the Birthplaces of Globular Clusters?
CORE Metadata, citation and similar papers at core.ac.uk Provided by CERN Document Server Paper I: To be submitted to A.J. Giant H II regions in the merging system NGC 3256: Are they the birthplaces of globular clusters? J. English University of Manitoba K.C. Freeman Research School of Astronomy and Astrophysics, The Australian National University ABSTRACT CCD images and spectra of ionized hydrogen in the merging system NGC3256 were acquired as part of a kinematic study to investigate the formation of globular clusters (GC) during the interactions and mergers of disk galaxies. This paper focuses on the proposition by Kennicutt & Chu (1988) that giant H II regions, with an Hα luminosity > 1:5 1040 erg s 1, are birthplaces of young populous clusters (YPC’s ). × − Although NGC 3256 has relatively few (7) giant H II complexes, compared to some other interacting systems, these regions are comparable in total flux to about 85 30- Doradus-like H II regions (30-Dor GHR’s). The bluest, massive YPC’s (Zepf et al. 1999) are located in the vicinity of observed 30-Dor GHR’s, contributing to the notion that some fraction of 30-Dor GHR’s do cradle massive YPC’s, as 30 Dor harbors R136. If interactions induce the formation of 30-Dor GHR’s, the observed luminosities indi- cate that almost 900 30-Dor GHR’s would form in NGC 3256 throughout its merger epoch. In order for 30-Dor GHR’s to be considered GC progenitors, this number must be consistent with the specific frequencies of globular clusters estimated for elliptical galaxies formed via mergers of spirals (Ashman & Zepf 1993). -
The State of Anthro–Earth
The Rosette Gazette Volume 22,, IssueIssue 7 Newsletter of the Rose City Astronomers July, 2010 RCA JULY 19 GENERAL MEETING The State Of Anthro–Earth THE STATE OF ANTHRO-EARTH: A Visitor From Far, Far Away Reviews the Status of Our Planet In This Issue: A Talk (in Earth-English) By Richard Brenne 1….General Meeting Enrico Fermi famously wondered why we hadn't heard from any other planetary 2….Club Officers civilizations, and Richard Brenne, who we'd always suspected was probably from another planet, thinks he might know the answer. Carl Sagan thought it was likely …...Magazines because those on other planets blew themselves up with nuclear weapons, but Richard …...RCA Library thinks its more likely that burning fossil fuels changed the climates and collapsed the 3….Local Happenings civilizations of those we might otherwise have heard from. Only someone from another planet could discuss this most serious topic with Richard's trademark humor 4…. Telescope (in a previous life he was an award-winning screenwriter - on which planet we're not Transformation sure) and bemused detachment. 5….Special Interest Groups Richard Brenne teaches a NASA-sponsored Global Climate Change class, serves on 6….Star Party Scene the American Meteorological Society's Committee to Communicate Climate Change, has written and produced documentaries about climate change since 1992, and has 7.…Observers Corner produced and moderated 50 hours of panel discussions about climate change with 18...RCA Board Minutes many of the world's top climate change scientists. Richard writes for the blog "Climate Progress" and his forthcoming book is titled "Anthro-Earth", his new name 20...Calendars for his adopted planet. -
Download the 2016 Spring Deep-Sky Challenge
Deep-sky Challenge 2016 Spring Southern Star Party Explore the Local Group Bonnievale, South Africa Hello! And thanks for taking up the challenge at this SSP! The theme for this Challenge is Galaxies of the Local Group. I’ve written up some notes about galaxies & galaxy clusters (pp 3 & 4 of this document). Johan Brink Peter Harvey Late-October is prime time for galaxy viewing, and you’ll be exploring the James Smith best the sky has to offer. All the objects are visible in binoculars, just make sure you’re properly dark adapted to get the best view. Galaxy viewing starts right after sunset, when the centre of our own Milky Way is visible low in the west. The edge of our spiral disk is draped along the horizon, from Carina in the south to Cygnus in the north. As the night progresses the action turns north- and east-ward as Orion rises, drawing the Milky Way up with it. Before daybreak, the Milky Way spans from Perseus and Auriga in the north to Crux in the South. Meanwhile, the Large and Small Magellanic Clouds are in pole position for observing. The SMC is perfectly placed at the start of the evening (it culminates at 21:00 on November 30), while the LMC rises throughout the course of the night. Many hundreds of deep-sky objects are on display in the two Clouds, so come prepared! Soon after nightfall, the rich galactic fields of Sculptor and Grus are in view. Gems like Caroline’s Galaxy (NGC 253), the Black-Bottomed Galaxy (NGC 247), the Sculptor Pinwheel (NGC 300), and the String of Pearls (NGC 55) are keen to be viewed. -
The VLT-FLAMES Tarantula Survey? XXIX
A&A 618, A73 (2018) Astronomy https://doi.org/10.1051/0004-6361/201833433 & c ESO 2018 Astrophysics The VLT-FLAMES Tarantula Survey? XXIX. Massive star formation in the local 30 Doradus starburst F. R. N. Schneider1, O. H. Ramírez-Agudelo2, F. Tramper3, J. M. Bestenlehner4,5, N. Castro6, H. Sana7, C. J. Evans2, C. Sabín-Sanjulián8, S. Simón-Díaz9,10, N. Langer11, L. Fossati12, G. Gräfener11, P. A. Crowther5, S. E. de Mink13, A. de Koter13,7, M. Gieles14, A. Herrero9,10, R. G. Izzard14,15, V. Kalari16, R. S. Klessen17, D. J. Lennon3, L. Mahy7, J. Maíz Apellániz18, N. Markova19, J. Th. van Loon20, J. S. Vink21, and N. R. Walborn22,?? 1 Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK e-mail: [email protected] 2 UK Astronomy Technology Centre, Royal Observatory Edinburgh, Blackford Hill, Edinburgh EH9 3HJ, UK 3 European Space Astronomy Centre, Mission Operations Division, PO Box 78, 28691 Villanueva de la Cañada, Madrid, Spain 4 Max-Planck-Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany 5 Department of Physics and Astronomy, Hicks Building, Hounsfield Road, University of Sheffield, Sheffield S3 7RH, UK 6 Department of Astronomy, University of Michigan, 1085 S. University Avenue, Ann Arbor, MI 48109-1107, USA 7 Institute of Astrophysics, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium 8 Departamento de Física y Astronomía, Universidad de La Serena, Avda. Juan Cisternas 1200, Norte, La Serena, Chile 9 Instituto de Astrofísica de Canarias, 38205 La Laguna, -
Ngc Catalogue Ngc Catalogue
NGC CATALOGUE NGC CATALOGUE 1 NGC CATALOGUE Object # Common Name Type Constellation Magnitude RA Dec NGC 1 - Galaxy Pegasus 12.9 00:07:16 27:42:32 NGC 2 - Galaxy Pegasus 14.2 00:07:17 27:40:43 NGC 3 - Galaxy Pisces 13.3 00:07:17 08:18:05 NGC 4 - Galaxy Pisces 15.8 00:07:24 08:22:26 NGC 5 - Galaxy Andromeda 13.3 00:07:49 35:21:46 NGC 6 NGC 20 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 7 - Galaxy Sculptor 13.9 00:08:21 -29:54:59 NGC 8 - Double Star Pegasus - 00:08:45 23:50:19 NGC 9 - Galaxy Pegasus 13.5 00:08:54 23:49:04 NGC 10 - Galaxy Sculptor 12.5 00:08:34 -33:51:28 NGC 11 - Galaxy Andromeda 13.7 00:08:42 37:26:53 NGC 12 - Galaxy Pisces 13.1 00:08:45 04:36:44 NGC 13 - Galaxy Andromeda 13.2 00:08:48 33:25:59 NGC 14 - Galaxy Pegasus 12.1 00:08:46 15:48:57 NGC 15 - Galaxy Pegasus 13.8 00:09:02 21:37:30 NGC 16 - Galaxy Pegasus 12.0 00:09:04 27:43:48 NGC 17 NGC 34 Galaxy Cetus 14.4 00:11:07 -12:06:28 NGC 18 - Double Star Pegasus - 00:09:23 27:43:56 NGC 19 - Galaxy Andromeda 13.3 00:10:41 32:58:58 NGC 20 See NGC 6 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 21 NGC 29 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 22 - Galaxy Pegasus 13.6 00:09:48 27:49:58 NGC 23 - Galaxy Pegasus 12.0 00:09:53 25:55:26 NGC 24 - Galaxy Sculptor 11.6 00:09:56 -24:57:52 NGC 25 - Galaxy Phoenix 13.0 00:09:59 -57:01:13 NGC 26 - Galaxy Pegasus 12.9 00:10:26 25:49:56 NGC 27 - Galaxy Andromeda 13.5 00:10:33 28:59:49 NGC 28 - Galaxy Phoenix 13.8 00:10:25 -56:59:20 NGC 29 See NGC 21 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 30 - Double Star Pegasus - 00:10:51 21:58:39 -
Arxiv:1803.10763V1 [Astro-Ph.GA] 28 Mar 2018
Draft version October 10, 2018 Typeset using LATEX default style in AASTeX61 TRACERS OF STELLAR MASS-LOSS - II. MID-IR COLORS AND SURFACE BRIGHTNESS FLUCTUATIONS Rosa A. Gonzalez-L´ opezlira´ 1 1Instituto de Radioastronomia y Astrofisica, UNAM, Campus Morelia, Michoacan, Mexico, C.P. 58089 (Received 2017 October 20; Revised 2018 February 20; Accepted 2018 February 21) Submitted to ApJ ABSTRACT I present integrated colors and surface brightness fluctuation magnitudes in the mid-IR, derived from stellar popula- tion synthesis models that include the effects of the dusty envelopes around thermally pulsing asymptotic giant branch (TP-AGB) stars. The models are based on the Bruzual & Charlot CB∗ isochrones; they are single-burst, range in age from a few Myr to 14 Gyr, and comprise metallicities between Z = 0.0001 and Z = 0.04. I compare these models to mid-IR data of AGB stars and star clusters in the Magellanic Clouds, and study the effects of varying self-consistently the mass-loss rate, the stellar parameters, and the output spectra of the stars plus their dusty envelopes. I find that models with a higher than fiducial mass-loss rate are needed to fit the mid-IR colors of \extreme" single AGB stars in the Large Magellanic Cloud. Surface brightness fluctuation magnitudes are quite sensitive to metallicity for 4.5 µm and longer wavelengths at all stellar population ages, and powerful diagnostics of mass-loss rate in the TP-AGB for intermediater-age populations, between 100 Myr and 2-3 Gyr. Keywords: stars: AGB and post{AGB | stars: mass-loss | Magellanic Clouds | infrared: stars | stars: evolution | galaxies: stellar content arXiv:1803.10763v1 [astro-ph.GA] 28 Mar 2018 Corresponding author: Rosa A. -
Parameters of Selected Central Stars of Planetary Nebulae from Consistent Optical and Uv Spectral Analysis
PARAMETERS OF SELECTED CENTRAL STARS OF PLANETARY NEBULAE FROM CONSISTENT OPTICAL AND UV SPECTRAL ANALYSIS Cornelius Bernhard Kaschinski PARAMETERS OF SELECTED CENTRAL STARS OF PLANETARY NEBULAE FROM CONSISTENT OPTICAL AND UV SPECTRAL ANALYSIS Dissertation Ph.D. Thesis an der Ludwig–Maximilians–Universitat¨ (LMU) Munchen¨ at the Ludwig–Maximilians–University (LMU) Munich fur¨ den Grad des for the degree of Doctor rerum naturalium vorgelegt von submitted by Cornelius Bernhard Kaschinski Munchen,¨ 2013 1st Evaluator: Prof. Dr. A. W. A. Pauldrach 2nd Evaluator: Prof. Dr. Barbara Ercolano Date of oral exam: 25.4.2013 Contents Contents vii List of Figures xii List of Tables xiii Zusammenfassung xv Abstract xvii 1 Introduction 1 1.1 Hot Stars . 1 1.1.1 Evolution of hot stars . 1 1.2 Impact of massive stars on the evolution of stellar clusters . 5 1.3 Motivation of this thesis . 5 1.4 Organization of this thesis . 8 2 Radiation-driven winds of hot luminous stars 11 XVII. Parameters of selected central stars of PN from consistent optical and UV spectral analysis and the universality of the mass–luminosity relation 2.1 Introduction . 12 2.2 Methods . 15 2.2.1 Parameter determination using hydrodynamic models and the UV spectrum . 15 2.2.2 Parameter determination using optical H and He lines . 18 2.2.3 Combined analysis . 19 2.3 Implementation of Stark broadening in the model atmosphere code WM-basic . 19 2.4 CSPN observational material . 25 2.5 Consistent optical and UV analysis of the CSPNs NGC 6826 and NGC 2392 . 25 2.5.1 NGC 6826 . -
The Changing Role of the 'Catts
Journal of Astronomical History and Heritage , 13(3), 235-254 (2010). THE CHANGING ROLE OF THE ‘CATTS TELESCOPE’: THE LIFE AND TIMES OF A NINETEENTH CENTURY 20-INCH GRUBB REFLECTOR Wayne Orchiston Centre for Astronomy, James Cook University, Townsville, Queensland 4811, Australia. [email protected] Abstract: An historic 20-in (50.8-cm) Grubb reflector originally owned by the London amateur astronomer, Henry Ellis, was transferred to Australia in 1928. After passing through a number of amateur owners the Catts Telescope— as it became known locally—was acquired by Mount Stromlo Observatory in 1952, and was then used for astrophysical research and for site-testing. In the mid-1960s the telescope was transferred to the University of Western Australia and was installed at Perth Observatory, but with other demands on the use of the dome it was removed in 1999 and placed in storage, thus ending a century of service to astronomy in England and Australia. Keywords: Catts Telescope, Henry Ellis, Walter Gale, Mount Stromlo Observatory, Mount Bingar field station, photoelectric photometry, spectrophotometry, Lawrence Aller, Bart Bok, Priscilla Bok, Olin Eggen, Don Faulkner, John Graham, Arthur Hogg, Gerald Kron, Pamela Kennedy, Antoni Przybylski, David Sher, Robert Shobbrook, Bengt Westerlund, John Whiteoak, Frank Bradshaw Wood. 1 INTRODUCTION what of other telescopes, like the 20-in (50.8-cm) ‘Catts Telescope’? After passing from amateur owner- One of the roles of the Historic Instruments Working ship to Mount Stromlo Observatory in 1952, this was Group of the IAU is to assemble national master lists used over the following twelve years to make a valu- of surviving historically-significant telescopes and able contribution to astrophysics and to provide data auxiliary instrumentation, and at the 2000 General for five different Ph.D. -
The R136 Star Cluster Dissected with Hubble Space Telescope/STIS
MNRAS 000, 1–39 (2015) Preprint 29 January 2016 Compiled using MNRAS LATEXstylefilev3.0 The R136 star cluster dissected with Hubble Space Telescope/STIS. I. Far-ultraviolet spectroscopic census and the origin of He ii λ1640 in young star clusters Paul A. Crowther1⋆, S.M. Caballero-Nieves1, K.A. Bostroem2,3,J.Ma´ız Apell´aniz4, F.R.N. Schneider5,6,N.R.Walborn2,C.R.Angus1,7,I.Brott8,A.Bonanos9, A. de Koter10,11,S.E.deMink10,C.J.Evans12,G.Gr¨afener13,A.Herrero14,15, I.D. Howarth16, N. Langer6,D.J.Lennon17,J.Puls18,H.Sana2,11,J.S.Vink13 1Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, UK 2Space Telescope Science Institute, 3700 San Martin Drive, Baltimore MD 21218, USA 3Department of Physics, University of California, Davis, 1 Shields Ave, Davis CA 95616, USA 4Centro de Astrobiologi´a, CSIC/INTA, Campus ESAC, Apartado Postal 78, E-28 691 Villanueva de la Ca˜nada, Madrid, Spain 5 Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH, UK 6 Argelanger-Institut fur¨ Astronomie der Universit¨at Bonn, Auf dem Hugel¨ 71, D-53121 Bonn, Germany 7 Department of Physics, University of Warwick, Gibbet Hill Rd, Coventry CV4 7AL, UK 8 Institute for Astrophysics, Tuerkenschanzstr. 17, AT-1180 Vienna, Austria 9 Institute of Astronomy & Astrophysics, National Observatory of Athens, I. Metaxa & Vas. Pavlou St, P. Penteli 15236, Greece 10 Astronomical Institute Anton Pannekoek, University of Amsterdam, Kruislaan 403, 1098 SJ, Amsterdam, Netherlands 11 Institute of Astronomy, KU Leuven, Celestijnenlaan -
19 91Apjs. . .76. .185E the Astrophysical Journal Supplement
The Astrophysical Journal Supplement Series, 76:185-214, 1991 May .185E © 1991. The American Astronomical Society. All rights reserved. Printed in U.S.A. .76. 91ApJS. THE STRUCTURE AND EVOLUTION OF RICH STAR CLUSTERS IN THE LARGE MAGELLANIC CLOUD 19 Rebecca A. W. Elson Bunting Institute, Radcliffe College; and Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 Received 1990 March 19; accepted 1990 September 14 ABSTRACT Surface brightness profiles and color-magnitude diagrams are presented for 18 rich star clusters in the Large Magellanic Cloud (LMC), with ages ~ 107-109 yr. The profiles of the older clusters are well represented by models with a King-like core. The profiles of many of the younger clusters show departures from such models in the form of bumps, sharp “shoulders,” and central dips. These features persist in profiles derived from images from which the bright stars have been subtracted; they therefore appear to reflect real substructure within the clusters. There is an upper limit to the radii of the cluster cores, and this upper limit increases with age from ^ 1 pc for the youngest clusters, to ^6 pc for the oldest ones. This trend probably reflects expansion of the cores driven by mass loss from evolving stars. Recent models of cluster evolution predict that the cores should expand at a rate that depends on the slope of the initial mass function ( IMF). In the context of these models, the data favor an IMF for most of the clusters with a slope slightly flatter than the Salpeter value (for the range of stellar masses 0.4-14M©), but with significant cluster-to-cluster variations. -
1970Aj 75. . 933H the Astronomical Journal
933H . 75. THE ASTRONOMICAL JOURNAL VOLUME 75, NUMBER 8 OCTOBER 1970 The System of Stellar Associations of the Large Magellanic Cloud 1970AJ Paul W. Hodge and Peter B. Lucke Astronomy Department, University of Washington, Seattle, Washington (Received 13 May 1970; revised 10 July 1970) From a study of the 122 recognized stellar O associations in the Large Magellanic Cloud it is found that the mean diameter is 78 pc, similar to the mean diameter of stellar associations recognized in the solar neigh- borhood. The mean number of stars with absolute visual magnitudes brighter than about —4 per 103 projected square parsecs in the associations is 19, while the mean total population of such stars is 18 per stellar association. Both of these figures are somewhat larger than the populations and the population densities of such stars in stellar associations near the sun. There is a considerable spread in the densities of bright stars in the LMC’s associations, but a general over-all correlation exists between the size of the asso- ciation and the total number of stars. Fifteen “star clouds” are recognized and these have a mean diameter of 225 pc, with total populations averaging 32 stars brighter than A/V= —4.2. In dimensions these objects are more similar to the objects studied in M31 by van den Bergh than are the majority of the stellar associa- tions in the LMC or our Galaxy. There is, however, no obvious discontinuity between the characteristics of the two kinds of objects. The radial distribution of the associations is shown in Fig. -
Open Clusters PAGING
Open Clusters in Turn Left at Orion (5th edition) Page Name Constellation RA Dec Chapter 193 NGC 129 Cassiopeia 0 H 29.8 min. 60° 14' North 210 NGC 220 Tucana 0 H 40.5 min. −73° 24' South 210 NGC 222 Tucana 0 H 40.7 min. −73° 23' South 210 NGC 231 Tucana 0 H 41.1 min. −73° 21' South 192 NGC 225 Cassiopeia 0 H 43.4 min. 61° 47' North 210 NGC 265 Tucana 0 H 47.2 min. −73° 29' South 202 NGC 188 Cepheus 0 H 47.5 min. 85° 15' North 210 NGC 330 Tucana 0 H 56.3 min. −72° 28' South 210 NGC 371 Tucana 1 H 3.4 min. −72° 4' South 210 NGC 376 Tucana 1 H 3.9 min. −72° 49' South 210 NGC 395 Tucana 1 H 5.1 min. −72° 0' South 210 NGC 460 Tucana 1 H 14.6 min. −73° 17' South 210 NGC 458 Tucana 1 H 14.9 min. −71° 33' South 193 NGC 436 Cassiopeia 1 H 15.5 min. 58° 49' North 210 NGC 465 Tucana 1 H 15.7 min. −73° 19' South 193 NGC 457 Cassiopeia 1 H 19.0 min. 58° 20' North 194 M103 Cassiopeia 1 H 33.2 min. 60° 42' North 179 NGC 604, in M33 Triangulum 1 H 34.5 min. 30° 47' October–December 195 NGC 637 Cassiopeia 1 H 41.8 min. 64° 2' North 195 NGC 654 Cassiopeia 1 H 43.9 min. 61° 54' North 195 NGC 659 Cassiopeia 1 H 44.2 min.