List of Publications Until 2008 Hilmar W
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FY08 Technical Papers by GSMTPO Staff
AURA/NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation July 23, 2008 Revised as Complete and Submitted December 23, 2008 NGC 660, ~13 Mpc from the Earth, is a peculiar, polar ring galaxy that resulted from two galaxies colliding. It consists of a nearly edge-on disk and a strongly warped outer disk. Image Credit: T.A. Rector/University of Alaska, Anchorage NATIONAL OPTICAL ASTRONOMY OBSERVATORY NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation December 23, 2008 TABLE OF CONTENTS EXECUTIVE SUMMARY ............................................................................................................................. 1 1 SCIENTIFIC ACTIVITIES AND FINDINGS ..................................................................................... 2 1.1 Cerro Tololo Inter-American Observatory...................................................................................... 2 The Once and Future Supernova η Carinae...................................................................................................... 2 A Stellar Merger and a Missing White Dwarf.................................................................................................. 3 Imaging the COSMOS...................................................................................................................................... 3 The Hubble Constant from a Gravitational Lens.............................................................................................. 4 A New Dwarf Nova in the Period Gap............................................................................................................ -
Annual Report 2016–2017 AAVSO
AAVSO The American Association of Variable Star Observers Annual Report 2016–2017 AAVSO Annual Report 2012 –2013 The American Association of Variable Star Observers AAVSO Annual Report 2016–2017 The American Association of Variable Star Observers 49 Bay State Road Cambridge, MA 02138-1203 USA Telephone: 617-354-0484 Fax: 617-354-0665 email: [email protected] website: https://www.aavso.org Annual Report Website: https://www.aavso.org/annual-report On the cover... At the 2017 AAVSO Annual Meeting.(clockwise from upper left) Knicole Colon, Koji Mukai, Dennis Conti, Kristine Larsen, Joey Rodriguez; Rachid El Hamri, Andy Block, Jane Glanzer, Erin Aadland, Jamin Welch, Stella Kafka; and (clockwise from upper left) Joey Rodriguez, Knicole Colon, Koji Mukai, Frans-Josef “Josch” Hambsch, Chandler Barnes. Picture credits In additon to images from the AAVSO and its archives, the editors gratefully acknowledge the following for their image contributions: Glenn Chaple, Shawn Dvorak, Mary Glennon, Bill Goff, Barbara Harris, Mario Motta, NASA, Gary Poyner, Msgr. Ronald Royer, the Mary Lea Shane Archives of the Lick Observatory, Chris Stephan, and Wheatley, et al. 2003, MNRAS, 345, 49. Table of Contents 1. About the AAVSO Vision and Mission Statement 1 About the AAVSO 1 What We Do 2 What Are Variable Stars? 3 Why Observe Variable Stars? 3 The AAVSO International Database 4 Observing Variable Stars 6 Services to Astronomy 7 Education and Outreach 9 2. The Year in Review Introduction 11 The 106th AAVSO Spring Membership Meeting, Ontario, California 11 The -
On the Progenitor of V838 Monocerotis
A&A 441, 1099–1109 (2005) Astronomy DOI: 10.1051/0004-6361:20042485 & c ESO 2005 Astrophysics On the progenitor of V838 Monocerotis R. Tylenda1,3,N.Soker2, and R. Szczerba1 1 Department for Astrophysics, N. Copernicus Astronomical Center, Rabianska´ 8, 87-100 Torun,´ Poland e-mail: [tylenda;szczerba]@ncac.torun.pl 2 Department of Physics, Technion-Israel Institute of Technology, 32000 Haifa, Israel e-mail: [email protected] 3 Centre for Astronomy, N. Copernicus University, 87-100 Torun,´ Poland Received 6 December 2004 / Accepted 9 June 2005 ABSTRACT We summarize and analyze the available observational data on the progenitor and the environment of V838 Mon. From the available photometric data for the progenitor of V838 Mon we exclude the possibility that the object before eruption was an evolved red giant star (AGB or RGB star). We find that most likely it was a main sequence or pre-main sequence star of ∼5−10 M. From the light echo structure and evolution we conclude that the reflecting dust is of interstellar nature rather than blown by V838 Mon in the past. We discuss the IRAS and CO data for interstellar medium observed near the position of V838 Mon. Several interstellar molecular regions have radial velocities similar to that of V838 Mon, so dust seen in the light echo might be related to one of them. Key words. stars: early-type – stars: binaries: close – stars: circumstellar matter – stars: individual: V838 Mon – ISM: reflection nebulae – ISM: structure 1. Introduction binary system which can be an important fact for identifying the outburst mechanism. -
Commission 27 of the Iau Information Bulletin
COMMISSION 27 OF THE I.A.U. INFORMATION BULLETIN ON VARIABLE STARS Nos. 3401 - 3500 1989 December - 1990 August EDITORS: L. SZABADOS and B. SZEIDL KONKOLY OBSERVATORY H-1525 BUDAPEST P.O. Box 67, HUNGARY HU ISSN 0374 - 0676 CONTENTS 3401 TWO-COLOUR-LIGHTCURVE AND PRELIMINARY ELEMENTS FOR AL Leo F. Agerer, D. Lichtenknecker 8 December 1989 3402 CCD PHOTOMETRY OF V1500 CYGNI IN 1987 AND 1989 R.E. Schmidt, J.A. DeYoung, B.C. Wagner 11 December 1989 3403 1988 LIGHT CURVES OF RX HERCULIS O. Demircan, E. Derman 12 December 1989 3404 1989 LIGHT CURVES OF BH Vir E. Derman, A. Akalin, O. Demircan 12 December 1989 3405 REMARK ON THE TWO DWARF NOVAE V632 CYGNI AND V630 CYGNI W. Wenzel 14 December 1989 3406 REVISED ELEMENTS AND LIGHT CURVE FOR LS Del M. Wieck, E. Wunder 18 December 1989 3407 RADIAL VELOCITIES OF SOME BRIGHT SOUTHERN STARS M. Clark 27 December 1989 3408 TIMES OF MINIMUM LIGHT FOR 16 ECLIPSES OF 8 APSIDAL MOTION BINARIES D.B. Caton, R.Lee Hawkins, W.C. Burns 27 December 1989 3409 PHOTOELECTRIC OBSERVATIONS OF UW Ori Zhang Rong-Xian, Zhang Ji-Tong, Li Qi-Sheng, Zhai Di-Sheng, Zhang Xiao-Yu 28 December 1989 3410 THE PERIOD OF KO Aur Zhang Rong-Xian, Zhang Ji-Tong, Zhai Di-Sheng 28 December 1989 3411 NOVA OPHIUCHI 1988 MONITORED 2.5 MONTHS AFTER OUTBURST R. Haefner 29 December 1989 3412 THE PERIOD OF Gamma DORADUS A.W.J. Cousins, J.A.R. Caldwell, J.W. Menzies 29 December 1989 3413 VARIABLE POLARIZATION IN A COMPARISON STAR OF V3885 Sgr K. -
Arxiv:Astro-Ph/0204354 V1 20 Apr 2002 1 DI Ilb Netdb Adlater) Hand by Inserted Be Will (DOI: Astrophysics & Astronomy H Uecn Dnicto Fi O a Confusing
Astronomy & Astrophysics manuscript no. June 3, 2005 (DOI: will be inserted by hand later) Recurrent Nova IM Normae Taichi Kato1, Hitoshi Yamaoka2, William Liller3, and Berto Monard4 1 Department of Astronomy, Kyoto University, Kyoto 606-8502, Japan 2 Faculty of Science, Kyushu University, Fukuoka 810-8560, Japan 3 Center for Nova Studies, Casilla 5022 Renaca, Vi˜na del Mar, Chile 4 Bronberg Observatory, PO Box 11426, Tiegerpoort 0056, South Africa Received / accepted Abstract. We detected the second historical outburst of the 1920 nova IM Nor. Accurate astrometry of the outbursting object revealed the true quiescent counterpart having a magnitude of R=17.0 mag and B=18.0 mag. We show that the quiescent counterpart shows a noticeable variation. From the comparison of light curves and spectroscopic signatures, we propose that IM Nor and CI Aql comprise a new class of recurrent novae bearing some characteristics similar to those of classical novae. We interpret that the noticeable quiescent variation can be a result of either high orbital inclination, which may be also responsible for the low quiescent brightness, or the presence of high/low states. If the second possibility is confirmed by future observations, IM Nor becomes the first recurrent nova showing state changes in quiescence. Such state changes may provide a missing link between recurrent novae and supersoft X-ray sources. Key words. novae, cataclysmic variables — Stars: individual (IM Nor) 1. Introduction nal studies, Duerbeck (1987) reported the remeasured po- sition of the nova, and different candidates for the qui- IM Nor was originally discovered as a possible nova in 1920 escent counterpart, whose exact identification remained by I. -
V838 Monocerotis Revisited: Space Phenomenon Imitates Art
HEIC0405: EMBARGOED UNTIL: 12:00 (CET)/6:00 (EST) 04 March, 2004 Photo release: V838 Monocerotis revisited: Space phenomenon imitates art 04-March-2004 "Starry Night", Vincent van Gogh's famous painting, is renowned for its bold whorls of light sweeping across a raging night sky. Although this image of the heavens came only from the artist's restless imagination, a new picture from the NASA/ESA Hubble Space Telescope bears remarkable similarities to the van Gogh work, complete with never-before-seen spirals of dust swirling across trillions of kilometres of interstellar space. This image, obtained with the Advanced Camera for Surveys on February 8, 2004, is Hubble's latest view of an expanding halo of light around a distant star, named V838 Monocerotis (V838 Mon). The illumination of interstellar dust comes from the red supergiant star at the middle of the image, which gave off a flashbulb-like pulse of light two years ago. V838 Mon is located about 20,000 light-years away from Earth in the direction of the constellation Monoceros, placing the star at the outer edge of our Milky Way galaxy. Called a light echo, the expanding illumination of a dusty cloud around the star has been revealing remarkable structures ever since the star suddenly brightened for several weeks in early 2002. Though Hubble has followed the light echo in several snapshots, this new image shows swirls or eddies in the dusty cloud for the first time. These eddies are probably caused by turbulence in the dust and gas around the star as they slowly expand away. -
Hubble Space Telescope Observations of the Light Echoes Around V838 Monocerotis
Asymmetric Planetary Nebulae III ASP Conference Series, Vol. XXX, 2004 M. Meixner, J. Kastner, B. Balick and N. Soker eds. Hubble Space Telescope Observations of the Light Echoes around V838 Monocerotis Howard E. Bond1, Arne Henden2, Zoltan G. Levay1, Nino Panagia1, William B. Sparks1, Sumner Starrfield3, R. Mark Wagner4, R. L. M. Corradi5, and U. Munari6 Abstract. The outburst of the unusual variable star V838 Monocero- tis is being accompanied by the most spectacular display of light echoes in the history of astronomy. We have imaged the echoes on 5 occasions in 2002 with the Hubble Space Telescope and its Advanced Camera for Surveys. Analysis of the angular expansion rates and polarimetry data yields a direct geometric distance (6 kpc), and establishes that the star was extremely luminous at the maximum of its outburst. Unlike a classi- cal nova, V838 Mon has remained a very cool red supergiant, and is now producing copious amounts of dust. The dust illuminated in the echoes was presumably ejected during previous similar outbursts. This event thus bears some similarities to the proto-PN ejection process from more normal AGB and post-AGB stars, and is of relevance to this conference. Light-echo imaging allows construction of fully 3-D maps of the dust dis- tribution, and we present a map based on these early observations. The dust is already seen to be highly non-spherical and non-homogeneous, similar to the structure inferred for many proto-PNe. 1. The Light-Echo Phenomenon A light echo is produced when a wave of illumination from a stellar outburst sweeps out into space. -
The Infrared Evolution of Dust in V838 Monocerotis C
Draft version August 19, 2021 Typeset using LATEX twocolumn style in AASTeX63 The Infrared Evolution of Dust in V838 Monocerotis C. E. Woodward ,1 A. Evans ,2 D. P. K. Banerjee ,3 T. Liimets ,4, 5 A. A. Djupvik ,6 S. Starrfield ,7 G. C. Clayton ,8 S. P. S. Eyres ,9 R. D. Gehrz ,1 and R. M. Wagner 10, 11 1Minnesota Institute for Astrophysics, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455, USA 2Astrophysics Group, Keele University, Keele, Staffordshire, ST5 5BG, UK 3Physical Research Laboratory, Navrangpura, Ahmedabad, Gujarat 380009, India 4Astronomick´y´ustav,Akademie vˇed Cesk´erepubliky,ˇ v.v.i., Friˇcova298, 251 65 Ondˇrejov,Czech Republic 5Tartu Observatory, University of Tartu, Observatooriumi 1, 61602 T~oravere, Estonia 6Nordic Optical Telescope, Rambla Jos´eAna Fern´andezP´erez 7, ES-38711 Bre~naBaja, Spain 7School of Earth and Space Exploration, Arizona State University, Box 871404, Tempe, AZ 85287-1404, USA 8Louisiana State University, Baton Rouge, Department of Physics & Astronomy Baton Rouge, LA 70803-001, USA 9Faculty of Computing, Engineering & Science, University of South Wales, Pontypridd, CF37 1DL, UK 10Department of Astronomy, The Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210, USA 11Large Binocular Telescope Observatory, 933 North Cherry Avenue, Tucson, AZ 85721, USA (Received 2021 June 21; Accepted 2021 August 17; Published To Appear in The Astronomical Journal) ABSTRACT Luminous Red Variables (LRVs) are most likely eruptions that are the outcome of stellar mergers. V838 Mon is one of the best-studied members of this class, representing an archetype for stellar mergers resulting from B-type stars. -
V838 Monocerotis: the Central Star and Its Environment a Decade After Outburst
A&A 569, L3 (2014) Astronomy DOI: 10.1051/0004-6361/201424458 & c ESO 2014 Astrophysics Letter to the Editor V838 Monocerotis: the central star and its environment a decade after outburst O. Chesneau1, , F. Millour1,O.DeMarco2,S.N.Bright1,2,A.Spang1,D.P.K.Banerjee3,N.M.Ashok3, T. Kaminski´ 4,J.P.Wisniewski5, A. Meilland1, and E. Lagadec1, 1 Laboratoire Lagrange, UMR 7293, Univ. Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, 06300 Nice, France e-mail: [email protected] 2 Department of Physics & Astronomy, Macquarie University, Sydney, NSW 2109, Australia 3 Physical Research Laboratory, Navrangpura, Ahmedabad, 380009 Gujarat, India 4 Max-Planck Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany 5 HL Dodge Department of Physics & Astronomy, University of Oklahoma, 440 W Brooks Street, Norman, OK 73019, USA Received 24 June 2014 / Accepted 21 July 2014 ABSTRACT Aims. V838 Monocerotis erupted in 2002, brightened in a series of outbursts, and eventually developed a spectacular light echo. A very red star emerged a few months after the outburst. The whole event has been interpreted as the result of a merger. Methods. We obtained near- and mid-IR interferometric observations of V838 Mon with the AMBER and MIDI recombiners located at the Very Large Telescope Interferometer (VLTI) array. The MIDI two-beam observations were obtained with the 8 m unit telescopes between October 2011 and February 2012. The AMBER three-beam observations were obtained with the compact array (B ≤ 35 m) in April 2013 and the long array (B ≤ 140 m) in May 2014, using the 1.8 m auxiliary telescopes. -
Introduction to Astronomy Lecture 6: an Astronomical Miscellany – Binaries, Clusters and Variables Presented by Dr Helen Johnston School of Physics
Introduction to Astronomy Lecture 6: An Astronomical Miscellany – binaries, clusters and variables Presented by Dr Helen Johnston School of Physics Spring 2018 The University of Sydney Page In tonight’s lecture • Binary stars • Variable stars • Irregular variables – stars that go bang • Regular variables – stars that pulsate • Clusters • Open clusters • Globular clusters • The binary connection The University of Sydney Page !2 Binary stars Binary stars Perhaps 80% of all the stars in the Galaxy are in some kind of double- or multiple-star system. Of the stars we can see, at least 50% are in fact multiple star systems. Somewhere between 5% and 15% are in systems of three or more stars. “Three out of every two stars are in a binary system.” – Cecilia Payne-Gaposhkin The University of Sydney Page !4 Their orbital separations range from many times the size of our Solar System, like Proxima Centauri, which orbits the inner binary of α Cen A and α Cen B at a distance of 13,000 AU, to distances so close that the two stars actually share a common atmosphere. Artist’s impression of the view from a planet orbiting a contact binary. The University of Sydney Painting by Don Dixon. Page !5 Some binaries (the visual binaries) can actually be seen directly. The two stars are separately visible in a telescope, and we can actually see them moving around one another. Castor (α Geminorum) is a visual binary with a separation of a couple of seconds of arc. The binary has not yet completed one 467-year orbit since The University of Sydney the first observations were made inPage !6 1719. -
Interacting Binaries No
Interacting Binaries No. 16, June 6, 2003 An Electronic Newsletter Editors: Boris T. Gansic¨ ke Dept. of Physics & Astronomy, University of Southampton, Southampton SO17 1BJ, UK Jens Kube Stiftung Alfred-Wegener-Institut fur¨ Polar- und Meeresforschung, Koldewey-Station, N-9173 Ny-Alesund,˚ Norway [email protected], http://astrocat.org/ibnews Contents 1 Editorial 2 2 Abstracts of refereed papers 3 – 1RXS J062518.2+733433: A new intermediate polar Araujo-Betancor et al. 3 – RX J0042.3+4115: a stellar mass black hole binary identified in M31 Barnard et al. 3 – Physical changes during Z-track movement in Sco X-1 on the flaring branch Barnard et al. 4 – Anomalous ultraviolet line flux ratios in the cataclysmic variables 1RXS J232953.9+062814, CE315, BZ UMa and EY Cyg observed with HST/STIS Gansic¨ ke et al. 4 – A new evolutionary channel for Type Ia supernovae King et al. 5 – CVcat: an interactive database on cataclysmic variables Kube et al. 5 – The Fe XXII I(11.92 A)/I(11.77˚ A)˚ Density Diagnostic Applied to the Chandra High Energy Trans- mission Grating Spectrum of EX Hydrae Mauche et al. 5 – The formation of the coronal flow/ADAF Meyer-Hofmeister & Meyer . 6 – The Origin of Soft X-rays in DQ Herculis Mukai et al. 6 – Looking for Dust and Molecules in Nova V4743 Sagittarii Nielbock & Schmidtobreick . 6 – Ultraviolet Spectra of CV Accretion Disks with Non-Steady T(r) Laws Orosz & Wade . 7 – On resonance line profiles predicted by radiation driven disk wind models. Proga . 7 – The emission distribution in RR Pictoris Schmidtobreick et al. -
Chapter 1. Impact
Atmosphere a Novel Excerpt Chapter 1. Impact our thousand and seventy years ago in a distant part of the Milky Way galaxy, a pair of gravitationally-linked stars began their death spiral, F rumbling into a super energetic state that culminated in a gamma-ray burst beamed at light speed into a then-barren region of the Milky Way. In the 21st Century A.D., the Earth was racing at half a million miles per hour towards a cataclysmic collision with the brief but devastating burst of raw energy from that ancient star explosion. In the city of Papeete, the capital of French Polynesia on the island of Tahiti, children from the local yacht club were on the water with a bevy of single sail dinghies, eight-foot-long training boats with seven-foot sails. Each boat had room for just one child, so the tiny flotilla of snub-nosed boats was being shepherded by two sailing instructors in a motorboat, busily keeping the students corralled within their marked sailing practice area. There was a light breeze, ideal conditions for the Optimus training fleet, with enough force to propel the dinghies wherever the sailors commanded, but not strong enough to flip the boats over. The instructors’ coaching could be clearly heard by the young sailors over the slapping of the waves gently jostling each boat. It was 5:42 in the afternoon of November 23, but the sun was still high. The Milky Way galaxy lay unseen directly overhead the French Polynesian Windward Islands when a blast from a galactic neighbor, a binary star system in the constellation Sagittarius the Archer, descended like Sagittarius’s arrow directly on top of the luckless Tahitians.