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From Luminous Hot Stars to Starburst Galaxies
9780521791342pre CUP/CONT July 9, 2008 11:48 Page-i FROM LUMINOUS HOT STARS TO STARBURST GALAXIES Luminous hot stars represent the extreme upper mass end of normal stellar evolution. Before exploding as supernovae, they live out their lives of only a few million years with prodigious outputs of radiation and stellar winds which dramatically affect both their evolution and environments. A detailed introduction to the topic, this book connects the astrophysics of mas- sive stars with the extremes of galaxy evolution represented by starburst phenomena. A thorough discussion of the physical and wind parameters of massive stars is pre- sented, together with considerations of their birth, evolution, and death. Hll galaxies, their connection to starburst galaxies, and the contribution of starburst phenomena to galaxy evolution through superwinds, are explored. The book concludes with the wider cosmological implications, including Population III stars, Lyman break galaxies, and gamma-ray bursts, for each of which massive stars are believed to play a crucial role. This book is ideal for graduate students and researchers in astrophysics who are interested in massive stars and their role in the evolution of galaxies. Peter S. Conti is an Emeritus Professor at the Joint Institute for Laboratory Astro- physics (JILA) and theAstrophysics and Planetary Sciences Department at the University of Colorado. Paul A. Crowther is a Professor of Astrophysics in the Department of Physics and Astronomy at the University of Sheffield. Claus Leitherer is an Astronomer with the Space Telescope Science Institute, Baltimore. 9780521791342pre CUP/CONT July 9, 2008 11:48 Page-ii Cambridge Astrophysics Series Series editors: Andrew King, Douglas Lin, Stephen Maran, Jim Pringle and Martin Ward Titles available in the series 10. -
The Hubble Tarantula Treasury Project
Mem. S.A.It. Vol. 89, 95 c SAIt 2018 Memorie della The Hubble Tarantula Treasury Project E. Sabbi and the HTTP Team Space Telescope Science Institute – 3700 San Martin Dr. 21218, Baltimore, MD USA e-mail: [email protected] Abstract. We present results from the Hubble Tarantula Treasury Project (HTTP), a Hubble Space Telescope panchromatic survey (from the near UV to the near IR) of the entire 30 Doradus region down to the sub-solar (∼ 0:5 M ) mass regime. The survey was done using the Wide Field Camera 3 and the Advanced Camera for Surveys in parallel. HTTP provides the first rich and statistically significant sample of intermediate- and low-mass pre-main se- quence candidates and allows us to trace how star formation has been developing through the region. We used synthetic color-magnitude diagrams (CMDs) to infer the star formation his- tory of the main clusters in the Tarantula Nebula, while the analysis of the pre-main sequence spatial distribution highlights the dual role of stellar feedback in quenching and triggering star formation on the giant Hii region scale. Key words. galaxies: star clusters: individual (30 Doradus, NGC2070, NGC2060, Hodge 301) – Magellanic Clouds – stars: formation – stars: massive – stars: pre-main sequence stars: evo- lution - stars: massive - stars: pre-main sequence 1. Introduction 1:3 × 10−8 erg cm−2 s−1, Kennicutt & Hodge 1986). Located in the Large Magellanic Cloud The Tarantula Nebula (also known as 30 (LMC), 30 Dor is the closest extragalactic gi- Doradus, hereafter ”30 Dor”) is one of the ant Hii region, and is comparable in size (∼ most famous objects in astronomy. -
The Luminosities of Cool Supergiants in the Magellanic Clouds, and the Humphreys-Davidson Limit Revisited
This is a repository copy of The luminosities of cool supergiants in the Magellanic Clouds, and the Humphreys-Davidson limit revisited. White Rose Research Online URL for this paper: http://eprints.whiterose.ac.uk/130065/ Version: Accepted Version Article: Davies, B., Crowther, P.A. and Beasor, E.R. (2018) The luminosities of cool supergiants in the Magellanic Clouds, and the Humphreys-Davidson limit revisited. Monthly Notices of the Royal Astronomical Society, 478 (3). pp. 3138-3148. ISSN 0035-8711 https://doi.org/10.1093/mnras/sty1302 This is a pre-copyedited, author-produced PDF of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. The version of record Ben Davies, Paul A Crowther, Emma R Beasor, The luminosities of cool supergiants in the Magellanic Clouds, and the Humphreys–Davidson limit revisited, Monthly Notices of the Royal Astronomical Society, Volume 478, Issue 3, August 2018, Pages 3138–3148, is available online at: https://doi.org/10.1093/mnras/sty1302 Reuse Items deposited in White Rose Research Online are protected by copyright, with all rights reserved unless indicated otherwise. They may be downloaded and/or printed for private study, or other acts as permitted by national copyright laws. The publisher or other rights holders may allow further reproduction and re-use of the full text version. This is indicated by the licence information on the White Rose Research Online record for the item. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request. -
Cfa in the News ~ Week Ending 3 January 2010
Wolbach Library: CfA in the News ~ Week ending 3 January 2010 1. New social science research from G. Sonnert and co-researchers described, Science Letter, p40, Tuesday, January 5, 2010 2. 2009 in science and medicine, ROGER SCHLUETER, Belleville News Democrat (IL), Sunday, January 3, 2010 3. 'Science, celestial bodies have always inspired humankind', Staff Correspondent, Hindu (India), Tuesday, December 29, 2009 4. Why is Carpenter defending scientists?, The Morning Call, Morning Call (Allentown, PA), FIRST ed, pA25, Sunday, December 27, 2009 5. CORRECTIONS, OPINION BY RYAN FINLEY, ARIZONA DAILY STAR, Arizona Daily Star (AZ), FINAL ed, pA2, Saturday, December 19, 2009 6. We see a 'Super-Earth', TOM BEAL; TOM BEAL, ARIZONA DAILY STAR, Arizona Daily Star, (AZ), FINAL ed, pA1, Thursday, December 17, 2009 Record - 1 DIALOG(R) New social science research from G. Sonnert and co-researchers described, Science Letter, p40, Tuesday, January 5, 2010 TEXT: "In this paper we report on testing the 'rolen model' and 'opportunity-structure' hypotheses about the parents whom scientists mentioned as career influencers. According to the role-model hypothesis, the gender match between scientist and influencer is paramount (for example, women scientists would disproportionately often mention their mothers as career influencers)," scientists writing in the journal Social Studies of Science report (see also ). "According to the opportunity-structure hypothesis, the parent's educational level predicts his/her probability of being mentioned as a career influencer (that ism parents with higher educational levels would be more likely to be named). The examination of a sample of American scientists who had received prestigious postdoctoral fellowships resulted in rejecting the role-model hypothesis and corroborating the opportunity-structure hypothesis. -
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. -
Carbon Stars T. Lloyd Evans
J. Astrophys. Astr. (2010) 31, 177–211 Carbon Stars T. Lloyd Evans SUPA, School of Physics and Astronomy, University of St. Andrews, North Haugh, St. Andrews, Fife KY16 9SS, UK. e-mail: [email protected] Received 2010 July 19; accepted 2010 October 18 Abstract. In this paper, the present state of knowledge of the carbon stars is discussed. Particular attention is given to issues of classification, evolution, variability, populations in our own and other galaxies, and circumstellar material. Key words. Stars: carbon—stars: evolution—stars: circumstellar matter —galaxies: magellanic clouds. 1. Introduction Carbon stars have been reviewed on several previous occasions, most recently by Wallerstein & Knapp (1998). A conference devoted to this topic was held in 1996 (Wing 2000) and two meetings on AGB stars (Le Bertre et al. 1999; Kerschbaum et al. 2007) also contain much on carbon stars. This review emphasizes develop- ments since 1997, while paying particular attention to connections with earlier work and to some of the important sources of concepts. Recent and ongoing develop- ments include surveys for carbon stars in more of the galaxies of the local group and detailed spectroscopy and infrared photometry for many of them, as well as general surveys such as 2MASS, AKARI and the Sirius near infrared survey of the Magel- lanic Clouds and several dwarf galaxies, the Spitzer-SAGE mid-infrared survey of the Magellanic Clouds and the current Herschel infrared satellite project. Detailed studies of relatively bright galactic examples continue to be made by high-resolution spectroscopy, concentrating on abundance determinations using the red spectral region, and infrared and radio observations which give information on the history of mass loss. -
Information to Users
A quantitative figure-of-merit approach for optimization of an unmanned Mars Sample Return mission Item Type text; Thesis-Reproduction (electronic) Authors Preiss, Bruce Kenneth, 1964- Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 06/10/2021 06:30:51 Link to Item http://hdl.handle.net/10150/278010 INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand corner and continuing from left to right in equal sections with small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back of the book. -
Atlas Menor Was Objects to Slowly Change Over Time
C h a r t Atlas Charts s O b by j Objects e c t Constellation s Objects by Number 64 Objects by Type 71 Objects by Name 76 Messier Objects 78 Caldwell Objects 81 Orion & Stars by Name 84 Lepus, circa , Brightest Stars 86 1720 , Closest Stars 87 Mythology 88 Bimonthly Sky Charts 92 Meteor Showers 105 Sun, Moon and Planets 106 Observing Considerations 113 Expanded Glossary 115 Th e 88 Constellations, plus 126 Chart Reference BACK PAGE Introduction he night sky was charted by western civilization a few thou - N 1,370 deep sky objects and 360 double stars (two stars—one sands years ago to bring order to the random splatter of stars, often orbits the other) plotted with observing information for T and in the hopes, as a piece of the puzzle, to help “understand” every object. the forces of nature. The stars and their constellations were imbued with N Inclusion of many “famous” celestial objects, even though the beliefs of those times, which have become mythology. they are beyond the reach of a 6 to 8-inch diameter telescope. The oldest known celestial atlas is in the book, Almagest , by N Expanded glossary to define and/or explain terms and Claudius Ptolemy, a Greco-Egyptian with Roman citizenship who lived concepts. in Alexandria from 90 to 160 AD. The Almagest is the earliest surviving astronomical treatise—a 600-page tome. The star charts are in tabular N Black stars on a white background, a preferred format for star form, by constellation, and the locations of the stars are described by charts. -
A FUSE Survey of Interstellar O VI Absorption in the Small Magellanic
Accepted for publication in the Astrophysical Journal A FUSE Survey of Interstellar O VI Absorption in the Small Magellanic Cloud Charles G. Hoopes1, Kenneth R. Sembach1,2, J. Christopher Howk1, Blair D. Savage3, and Alex W. Fullerton1,4 ABSTRACT We present the results of a Far Ultraviolet Spectroscopic Explorer (FUSE) survey of O VI 1031.93 A˚ and 1037.62 A˚ absorption toward 18 OB stars in the Small Magellanic Cloud (SMC). The FUSE data are of very high quality, allowing a detailed study of the coronal temperature gas in the SMC. We find that O VI is ubiquitous in the SMC, with a detection along every sight line. The average value of the O VI column density in the SMC is log < N(O VI)>= 14.53. This value is 1.7 times higher than the average value for the Milky Way halo (perpendicular to the Galactic plane) of log N⊥(O VI)=14.29 found by FUSE, even though the SMC has much lower metallicity than the Galaxy. The column density in the SMC is higher along sight lines that lie close to star-forming regions, in particular NGC 346 in the northern part of the SMC, and to a lesser degree the southwestern complex of H II regions. This correlation with star formation suggests that local processes have an important effect on the distribution of coronal gas in the SMC. If the sight lines within NGC 346 are excluded, the mean column density for the SMC is log N(O VI)= 14.45, only 1.4 times higher than the Milky Way average. -
FY13 High-Level Deliverables
National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2013 (1 October 2012 – 30 September 2013) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 13 December 2013 Revised 18 September 2014 Contents NOAO MISSION PROFILE .................................................................................................... 1 1 EXECUTIVE SUMMARY ................................................................................................ 2 2 NOAO ACCOMPLISHMENTS ....................................................................................... 4 2.1 Achievements ..................................................................................................... 4 2.2 Status of Vision and Goals ................................................................................. 5 2.2.1 Status of FY13 High-Level Deliverables ............................................ 5 2.2.2 FY13 Planned vs. Actual Spending and Revenues .............................. 8 2.3 Challenges and Their Impacts ............................................................................ 9 3 SCIENTIFIC ACTIVITIES AND FINDINGS .............................................................. 11 3.1 Cerro Tololo Inter-American Observatory ....................................................... 11 3.2 Kitt Peak National Observatory ....................................................................... 14 3.3 Gemini Observatory ........................................................................................ -
Jahresbericht 2010 Mitteilungen Der Astronomischen Gesellschaft 94 (2013), 583–627
Jahresbericht 2010 Mitteilungen der Astronomischen Gesellschaft 94 (2013), 583–627 Potsdam Leibniz-Institut für Astrophysik Potsdam (AIP) An der Sternwarte 16, D-14482 Potsdam Tel. 03317499-0, Telefax: 03317499-267 E-Mail: [email protected] WWW: http://www.aip.de Beobachtungseinrichtungen Robotisches Observatorium STELLA Observatorio del Teide, Izaña E-38205 La Laguna, Teneriffa, Spanien Tel. +34 922 329 138 bzw. 03317499-633 LOFAR-Station DE604 Potsdam-Bornim D-14469 Potsdam Tel. 03317499-291, Telefax: 03317499-352 Observatorium für Solare Radioastronomie Tremsdorf D-14552 Tremsdorf Tel. 03317499-291, Telefax: 03317499-352 Sonnenobservatorium Einsteinturm Telegrafenberg, D-14473 Potsdam Tel. 0331288-2303/-2304, Telefax: 03317499-524 0 Allgemeines Das Leibniz-Institut für Astrophysik Potsdam (AIP) ist eine Stiftung bürgerlichen Rechts zum Zweck der wissenschaftlichen Forschung auf dem Gebiet der Astrophysik. Als außer- universitäre Forschungseinrichtung ist es Mitglied der Leibniz-Gemeinschaft. Seinen For- schungsauftrag führt das AIP im Rahmen von nationalen und internationalen Kooperatio- nen aus. Die Beteiligung am Large Binocular Telescope auf dem Mt Graham in Arizona, dem größten optischen Teleskop der Welt, verdient hierbei besondere Erwähnung. Neben seinen Forschungsarbeiten profiliert sich das Institut zunehmend als Kompetenzzentrum im Bereich der Entwicklung von Forschungstechnologie. Vier gemeinsame Berufungen mit der Universität Potsdam und mehrere außerplanmäßige Professuren und Privatdozenturen an Universitäten in der Region und -
STAR FORMATION (Ch. 19)
STAR FORMATION (Ch. 19) The basics: GRAVITY vs. PRESSURE (heat; but also rotation and magnetic fields can be important) Stages (you don’t have to memorize numbers of stages in textbook or here, just be able to describe the sequence of events) 1. Interstellar cloud—cold (T~10K), large (~1-10pc), massive 3 5 (~10 – 10 Msun), so gravity wins easily over gas pressure (atomic motions—see Fig. 19.2): cloud must break up, or “fragment.” Other inhibitors: rotation, magnetic fields (More Precisely 19-1, p. 503). 2. Collapsing cloud fragment—still cold, size~0.1-0.01pc. This may fragment further, so have multiple stages of fragmentation (see Fig. 19.3). 3. Fragmentation ceases—center of fragment dense enough to become opaque to its own radiation, so it heats up, slowing the collapse. (Previously it was transparent and so could stay cool because radiation escaped easily.) This property makes qualifies the object as a: 4. Protostar—now object has a “surface” because it is opaque; this surface is the photosphere (the layer where the photons can finally escape into space). So a protostar is defined by when the object becomes dense enough to have a photosphere. It appears in the H-R diagram in upper right (large! See Fig. 19.4) Protostar heats up by gravitational contraction and accretion of remaining material (from a disk). But the temperature in center is too low for nuclear reactions at this stage. 5. Continued slow contraction (getting fainter), heating. Protostar moves roughly on a vertical track in the H-R diagram (see Fig.