New Magnetic Cyclone Model, Bombogenesis, Associated Supernova and Nova Effects
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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............................................................................................................ -
A Hot Subdwarf-White Dwarf Super-Chandrasekhar Candidate
A hot subdwarf–white dwarf super-Chandrasekhar candidate supernova Ia progenitor Ingrid Pelisoli1,2*, P. Neunteufel3, S. Geier1, T. Kupfer4,5, U. Heber6, A. Irrgang6, D. Schneider6, A. Bastian1, J. van Roestel7, V. Schaffenroth1, and B. N. Barlow8 1Institut fur¨ Physik und Astronomie, Universitat¨ Potsdam, Haus 28, Karl-Liebknecht-Str. 24/25, D-14476 Potsdam-Golm, Germany 2Department of Physics, University of Warwick, Coventry, CV4 7AL, UK 3Max Planck Institut fur¨ Astrophysik, Karl-Schwarzschild-Straße 1, 85748 Garching bei Munchen¨ 4Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106, USA 5Texas Tech University, Department of Physics & Astronomy, Box 41051, 79409, Lubbock, TX, USA 6Dr. Karl Remeis-Observatory & ECAP, Astronomical Institute, Friedrich-Alexander University Erlangen-Nuremberg (FAU), Sternwartstr. 7, 96049 Bamberg, Germany 7Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA 8Department of Physics and Astronomy, High Point University, High Point, NC 27268, USA *[email protected] ABSTRACT Supernova Ia are bright explosive events that can be used to estimate cosmological distances, allowing us to study the expansion of the Universe. They are understood to result from a thermonuclear detonation in a white dwarf that formed from the exhausted core of a star more massive than the Sun. However, the possible progenitor channels leading to an explosion are a long-standing debate, limiting the precision and accuracy of supernova Ia as distance indicators. Here we present HD 265435, a binary system with an orbital period of less than a hundred minutes, consisting of a white dwarf and a hot subdwarf — a stripped core-helium burning star. -
Unknown Amorphous Carbon II. LRS SPECTRA the Sample Consists Of
Table I A summary of the spectral -features observed in the LRS spectra of the three groups o-f carbon stars. The de-finition o-f the groups is given in the text. wavelength Xmax identification Group I B - 12 urn E1 9.7 M™ Silicate 12 - 23 jim E IB ^m Silicate Group II < 8.5 M"i A C2H2 CS? 12 - 16 f-i/n A 13.7 - 14 Mm C2H2 HCN? 8 - 10 Mm E 8.6 M"i Unknown 10 - 13 Mm E 11.3 - 11 .7 M«> SiC Group III 10 - 13 MJn E 11.3 - 11 .7 tun SiC B - 23 Htn C Amorphous carbon 1 The letter in this column indicates the nature o-f the -feature: A = absorption; E = emission; C indicates the presence of continuum opacity. II. LRS SPECTRA The sample consists of 304 carbon stars with entries in the LRS catalog (Papers I-III). The LRS spectra have been divided into three groups. Group I consists of nine stars with 9.7 and 18 tun silicate features in their LRS spectra pointing to oxygen-rich dust in the circumstellar shell. These sources are discussed in Paper I. The remaining stars all have spectra with carbon-rich dust features. Using NIR photometry we have shown that in the group II spectra the stellar photosphere is the dominant continuum. The NIR color temperature is of the order of 25OO K. Paper II contains a discussion of sources with this class of spectra. The continuum in the group III spectra is probably due to amorphous carbon dust. -
JOHN R. THORSTENSEN Address
CURRICULUM VITAE: JOHN R. THORSTENSEN Address: Department of Physics and Astronomy Dartmouth College 6127 Wilder Laboratory Hanover, NH 03755-3528; (603)-646-2869 [email protected] Undergraduate Studies: Haverford College, B. A. 1974 Astronomy and Physics double major, High Honors in both. Graduate Studies: Ph. D., 1980, University of California, Berkeley Astronomy Department Dissertation : \Optical Studies of Faint Blue X-ray Stars" Graduate Advisor: Professor C. Stuart Bowyer Employment History: Department of Physics and Astronomy, Dartmouth College: { Professor, July 1991 { present { Associate Professor, July 1986 { July 1991 { Assistant Professor, September 1980 { June 1986 Research Assistant, Space Sciences Lab., U.C. Berkeley, 1975 { 1980. Summer Student, National Radio Astronomy Observatory, 1974. Summer Student, Bartol Research Foundation, 1973. Consultant, IBM Corporation, 1973. (STARMAP program). Honors and Awards: Phi Beta Kappa, 1974. National Science Foundation Graduate Fellow, 1974 { 1977. Dorothea Klumpke Roberts Award of the Berkeley Astronomy Dept., 1978. Professional Societies: American Astronomical Society Astronomical Society of the Pacific International Astronomical Union Lifetime Publication List * \Can Collapsed Stars Close the Universe?" Thorstensen, J. R., and Partridge, R. B. 1975, Ap. J., 200, 527. \Optical Identification of Nova Scuti 1975." Raff, M. I., and Thorstensen, J. 1975, P. A. S. P., 87, 593. \Photometry of Slow X-ray Pulsars II: The 13.9 Minute Period of X Persei." Margon, B., Thorstensen, J., Bowyer, S., Mason, K. O., White, N. E., Sanford, P. W., Parkes, G., Stone, R. P. S., and Bailey, J. 1977, Ap. J., 218, 504. \A Spectrophotometric Survey of the A 0535+26 Field." Margon, B., Thorstensen, J., Nelson, J., Chanan, G., and Bowyer, S. -
DIRECT DETECTION of the L-DWARF DONOR in WZ SAGITTAE Thomas E
The Astrophysical Journal, 816:4 (6pp), 2016 January 1 doi:10.3847/0004-637X/816/1/4 © 2016. The American Astronomical Society. All rights reserved. DIRECT DETECTION OF THE L-DWARF DONOR IN WZ SAGITTAE Thomas E. Harrison1 Department of Astronomy, New Mexico State University, Box 30001, MSC 4500, Las Cruces, NM 88003-8001, USA Received 2015 September 15; accepted 2015 November 20; published 2015 December 21 ABSTRACT Analysis of a large set of phase-resolved K-band spectra of the cataclysmic variable WZ Sge shows that the secondary star of this system appears to be an L-dwarf. Previous K-band spectra of WZ Sge found that the CO 12 overtone bandheads were in emission. We show that absorption from the CO(2,0) bandhead of the donor star 12 creates a dip in the CO(2,0) emission feature. Measuring the motion of this feature over the orbital period, we −1 construct a radial velocity curve that gives a velocity amplitude of Kabs = 520±35 km s , consistent with the previously published values for this parameter. Key words: brown dwarfs – novae, cataclysmic variables – stars: dwarf novae 1. INTRODUCTION Harrison et al. 2004a) and has a very low accretion rate (Patterson 1998), the donor object has remained elusive. Cataclysmic variables (CVs) are short period binaries where While direct photospheric absorption features from the donor the white dwarf primary is accreting matter from a lower mass in WZ Sge have not previously been detected, Hα emission, secondary star. An angular momentum loss process keeps the ( ) due to the irradiation of the companion during the 2001 system in contact c.f., King & Kolb 1995 , and the orbital outburst, were clearly seen, and led to the first quantitative period shortens over time as the secondary continues to lose constraints on the nature of the secondary. -
Recent Advances in Research on Tropical Cyclogenesis
Available online at www.sciencedirect.com ScienceDirect Tropical Cyclone Research and Review 9 (2020) 87e105 www.keaipublishing.com/tcrr Recent advances in research on tropical cyclogenesis Brian H. Tang a,*, Juan Fang b, Alicia Bentley a,y, Gerard Kilroy c, Masuo Nakano d, Myung-Sook Park e, V.P.M. Rajasree f, Zhuo Wang g, Allison A. Wing h, Liguang Wu i a University at Albany, State University of New York, Albany, USA b Nanjing University, Nanjing, China c Ludwig-Maximilians University of Munich, Munich, Germany d Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan e Korea Institute of Ocean Science and Technology, Busan, South Korea f Centre for Atmospheric and Climate Physics Research, University of Hertfordshire, Hatfield, UK g University of Illinois, Urbana, USA h Florida State University, Tallahassee, USA i Fudan University, Shanghai, China Available online 7 May 2020 Abstract This review article summarizes recent (2014e2019) advances in our understanding of tropical cyclogenesis, stemming from activities at the ninth International Workshop on Tropical Cyclones. Tropical cyclogenesis involves the interaction of dynamic and thermodynamic processes at multiple spatio-temporal scales. Studies have furthered our understanding of how tropical cyclogenesis may be affected by external processes, such as intraseasonal oscillations, monsoon circulations, the intertropical convergence zone, and midlatitude troughs and cutoff lows. Addi- tionally, studies have furthered our understanding of how tropical cyclogenesis may be affected by internal processes, such as the organization of deep convection; the evolution of the “pouch” structure; the role of friction; the development of the moist, warm core; the importance of surface fluxes; and the role of the mid-level vortex. -
September 2020 BRAS Newsletter
A Neowise Comet 2020, photo by Ralf Rohner of Skypointer Photography Monthly Meeting September 14th at 7:00 PM, via Jitsi (Monthly meetings are on 2nd Mondays at Highland Road Park Observatory, temporarily during quarantine at meet.jit.si/BRASMeets). GUEST SPEAKER: NASA Michoud Assembly Facility Director, Robert Champion What's In This Issue? President’s Message Secretary's Summary Business Meeting Minutes Outreach Report Asteroid and Comet News Light Pollution Committee Report Globe at Night Member’s Corner –My Quest For A Dark Place, by Chris Carlton Astro-Photos by BRAS Members Messages from the HRPO REMOTE DISCUSSION Solar Viewing Plus Night Mercurian Elongation Spooky Sensation Great Martian Opposition Observing Notes: Aquila – The Eagle Like this newsletter? See PAST ISSUES online back to 2009 Visit us on Facebook – Baton Rouge Astronomical Society Baton Rouge Astronomical Society Newsletter, Night Visions Page 2 of 27 September 2020 President’s Message Welcome to September. You may have noticed that this newsletter is showing up a little bit later than usual, and it’s for good reason: release of the newsletter will now happen after the monthly business meeting so that we can have a chance to keep everybody up to date on the latest information. Sometimes, this will mean the newsletter shows up a couple of days late. But, the upshot is that you’ll now be able to see what we discussed at the recent business meeting and have time to digest it before our general meeting in case you want to give some feedback. Now that we’re on the new format, business meetings (and the oft neglected Light Pollution Committee Meeting), are going to start being open to all members of the club again by simply joining up in the respective chat rooms the Wednesday before the first Monday of the month—which I encourage people to do, especially if you have some ideas you want to see the club put into action. -
Variable Star Classification and Light Curves Manual
Variable Star Classification and Light Curves An AAVSO course for the Carolyn Hurless Online Institute for Continuing Education in Astronomy (CHOICE) This is copyrighted material meant only for official enrollees in this online course. Do not share this document with others. Please do not quote from it without prior permission from the AAVSO. Table of Contents Course Description and Requirements for Completion Chapter One- 1. Introduction . What are variable stars? . The first known variable stars 2. Variable Star Names . Constellation names . Greek letters (Bayer letters) . GCVS naming scheme . Other naming conventions . Naming variable star types 3. The Main Types of variability Extrinsic . Eclipsing . Rotating . Microlensing Intrinsic . Pulsating . Eruptive . Cataclysmic . X-Ray 4. The Variability Tree Chapter Two- 1. Rotating Variables . The Sun . BY Dra stars . RS CVn stars . Rotating ellipsoidal variables 2. Eclipsing Variables . EA . EB . EW . EP . Roche Lobes 1 Chapter Three- 1. Pulsating Variables . Classical Cepheids . Type II Cepheids . RV Tau stars . Delta Sct stars . RR Lyr stars . Miras . Semi-regular stars 2. Eruptive Variables . Young Stellar Objects . T Tau stars . FUOrs . EXOrs . UXOrs . UV Cet stars . Gamma Cas stars . S Dor stars . R CrB stars Chapter Four- 1. Cataclysmic Variables . Dwarf Novae . Novae . Recurrent Novae . Magnetic CVs . Symbiotic Variables . Supernovae 2. Other Variables . Gamma-Ray Bursters . Active Galactic Nuclei 2 Course Description and Requirements for Completion This course is an overview of the types of variable stars most commonly observed by AAVSO observers. We discuss the physical processes behind what makes each type variable and how this is demonstrated in their light curves. Variable star names and nomenclature are placed in a historical context to aid in understanding today’s classification scheme. -
Report on UN ESCAP / WMO Typhoon Committee Members Disaster Management System
Report on UN ESCAP / WMO Typhoon Committee Members Disaster Management System UNITED NATIONS Economic and Social Commission for Asia and the Pacific January 2009 Disaster Management ˆ ` 2009.1.29 4:39 PM ˘ ` 1 ¿ ‚fiˆ •´ lp125 1200DPI 133LPI Report on UN ESCAP/WMO Typhoon Committee Members Disaster Management System By National Institute for Disaster Prevention (NIDP) January 2009, 154 pages Author : Dr. Waonho Yi Dr. Tae Sung Cheong Mr. Kyeonghyeok Jin Ms. Genevieve C. Miller Disaster Management ˆ ` 2009.1.29 4:39 PM ˘ ` 2 ¿ ‚fiˆ •´ lp125 1200DPI 133LPI WMO/TD-No. 1476 World Meteorological Organization, 2009 ISBN 978-89-90564-89-4 93530 The right of publication in print, electronic and any other form and in any language is reserved by WMO. Short extracts from WMO publications may be reproduced without authorization, provided that the complete source is clearly indicated. Editorial correspon- dence and requests to publish, reproduce or translate this publication in part or in whole should be addressed to: Chairperson, Publications Board World Meteorological Organization (WMO) 7 bis, avenue de la Paix Tel.: +41 (0) 22 730 84 03 P.O. Box No. 2300 Fax: +41 (0) 22 730 80 40 CH-1211 Geneva 2, Switzerland E-mail: [email protected] NOTE The designations employed in WMO publications and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of WMO concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. -
Ludwig Neidhart
© Dr. Ludwig Neidhart, 1998, 2007 „Als die Zeit erfüllt war ...“ Ein Diskussionsbeitrag zu Grundproblemen der biblischen Weihnachtgeschichte und der Datierung der Geburt Christi von Ludwig Neidhart (überarbeitete Version, Stand 07.04.2019) Erstmals erschienen in: Brücke zum Menschen Nr. 133, 1. Quartal 1998 Leicht überarbeitete Version in: Pro Sancta Ecclesia Nr. 21, 2007, S. 20–110 Auszug mit dem Titel ‚Die Magier und der Stern’ in: Dörthe Emig-Herchen (Hg.), Silberglanz in stillen Gassen. Weihnachts-Anthologie 2007, Frankfurt a.M., 2007, S. 221–246 Inhaltsverzeichnis 1. Wie kam man auf den 25. Dezember?...................................................................................................2 2. Wie alt ist das Geburtsfest Christi am 25. Dezember?........................................................................3 3. Frühchristliche Traditionen über den Geburtstag Jesu......................................................................4 4. Kann Christus im Dezember geboren sein?.........................................................................................7 5. Biblische Chronologie des Lebens Christi............................................................................................8 5.1. Die Dauer des öffentlichen Wirkens Jesu......................................................................................8 5.2. Jesus starb am 7. April des Jahres 30.............................................................................................9 5.3. Exkurs über die Stunde der Kreuzigung.....................................................................................13 -
Minnesota Weathertalk Newsletter for Friday, January 3, 2014
Minnesota WeatherTalk Newsletter for Friday, January 3, 2014 To: MPR's Morning Edition From: Mark Seeley, Univ. of Minnesota, Dept of Soil, Water, and Climate Subject: Minnesota WeatherTalk Newsletter for Friday, January 3, 2014 HEADLINES -December 2013 was climate near historic for northern communities -Cold start to 2014 -Weekly Weather potpourri -MPR listener questions -Almanac for January 3rd -Past weather -Outlook Topic: December 2013 near historic for far north In assessing the climate for December 2013 it should be said that from the standpoint of cold temperatures the month was quite historic for many northern Minnesota communities, especially due to the Arctic cold that prevailed over the last few days of the month. Minnesota reported the coldest temperature in the 48 contiguous states thirteen times during the month, the highest frequency among all 48 states. Many northern observers saw overnight temperatures drop below -30 degrees F on several occasions. The mean monthly temperature for December from several communities ranked among the coldest Decembers ever. A sample listing includes: -4.1 F at International Falls, 2nd coldest all-time 4.6 F at Duluth, 8th coldest all-time 0.1 F at Crookston, 3rd coldest all-time -3.1 F at Roseau, 3rd coldest all-time 0.3 F at Park Rapids, 3rd coldest all-time -4.4 F at Embarrass, 2nd coldest all-time -4.1 F at Baudette, coldest all-time -3.7 F at Warroad, coldest all-time -2.9 F at Babbitt, coldest all-time -2.8 F at Gunflint Lake, coldest all-time In addition, some communities reported an exceptionally snowy month of December. -
Stars and Their Spectra: an Introduction to the Spectral Sequence Second Edition James B
Cambridge University Press 978-0-521-89954-3 - Stars and Their Spectra: An Introduction to the Spectral Sequence Second Edition James B. Kaler Index More information Star index Stars are arranged by the Latin genitive of their constellation of residence, with other star names interspersed alphabetically. Within a constellation, Bayer Greek letters are given first, followed by Roman letters, Flamsteed numbers, variable stars arranged in traditional order (see Section 1.11), and then other names that take on genitive form. Stellar spectra are indicated by an asterisk. The best-known proper names have priority over their Greek-letter names. Spectra of the Sun and of nebulae are included as well. Abell 21 nucleus, see a Aurigae, see Capella Abell 78 nucleus, 327* ε Aurigae, 178, 186 Achernar, 9, 243, 264, 274 z Aurigae, 177, 186 Acrux, see Alpha Crucis Z Aurigae, 186, 269* Adhara, see Epsilon Canis Majoris AB Aurigae, 255 Albireo, 26 Alcor, 26, 177, 241, 243, 272* Barnard’s Star, 129–130, 131 Aldebaran, 9, 27, 80*, 163, 165 Betelgeuse, 2, 9, 16, 18, 20, 73, 74*, 79, Algol, 20, 26, 176–177, 271*, 333, 366 80*, 88, 104–105, 106*, 110*, 113, Altair, 9, 236, 241, 250 115, 118, 122, 187, 216, 264 a Andromedae, 273, 273* image of, 114 b Andromedae, 164 BDþ284211, 285* g Andromedae, 26 Bl 253* u Andromedae A, 218* a Boo¨tis, see Arcturus u Andromedae B, 109* g Boo¨tis, 243 Z Andromedae, 337 Z Boo¨tis, 185 Antares, 10, 73, 104–105, 113, 115, 118, l Boo¨tis, 254, 280, 314 122, 174* s Boo¨tis, 218* 53 Aquarii A, 195 53 Aquarii B, 195 T Camelopardalis,