Spectral Classification of B-Type Stars
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FOIA Logs for US Army for 2000
Description of document: FOIA CASE LOGS for: United States Army, Alexandria, VA for 2000 - 2003 Released date: 2003 Posted date: 04-March-2008 Date/date range of document: 03-January-2000 – 27-March-2003 Source of document: Department Of The Army U.S. Army Freedom of Information and Privacy Office Casey Building, Suite 144 Attn: JDRP-RDF 7701 Telegraph Road Alexandria, VA 22315-3905 Phone: (703) 428-6494 Fax: (703) 428-6522 Email: [email protected] The governmentattic.org web site (“the site”) is noncommercial and free to the public. The site and materials made available on the site, such as this file, are for reference only. The governmentattic.org web site and its principals have made every effort to make this information as complete and as accurate as possible, however, there may be mistakes and omissions, both typographical and in content. The governmentattic.org web site and its principals shall have neither liability nor responsibility to any person or entity with respect to any loss or damage caused, or alleged to have been caused, directly or indirectly, by the information provided on the governmentattic.org web site or in this file 2000 FOIA# Rec'd Closed Susp Days Subject Refer By Control # Class AO Action 1 Action 2 Action 3 # Refer Q 00-0433 01/03/2000 04/06/2000 01/14/2000 67 Information on what the name or number of the group or company U SLF CATEGORY 9 0 S stationed in St. John's, Newfoundland during World War II in 1945 (E-Mail) 00-0434 01/03/2000 01/04/2000 01/14/2000 2 Information on the mortality rate of the former -
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A&A 601, A29 (2017) Astronomy DOI: 10.1051/0004-6361/201629685 & c ESO 2017 Astrophysics Delay-time distribution of core-collapse supernovae with late events resulting from binary interaction E. Zapartas1, S. E. de Mink1, R. G. Izzard2, S.-C. Yoon3, C. Badenes4, Y. Götberg1, A. de Koter1; 5, C. J. Neijssel1, M. Renzo1, A. Schootemeijer6, and T. S. Shrotriya6 1 Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands e-mail: [E.Zapartas;S.E.deMink]@uva.nl 2 Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK 3 Astronomy Program, Department of Physics and Astronomy, Seoul National University, 151–747 Seoul, Korea 4 Department of Physics and Astronomy & Pittsburgh Particle Physics, Astrophysics, and Cosmology Center (PITT-PACC), University of Pittsburgh, Pittsburgh, PA 15260, USA 5 Institute of Astronomy, KU Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium 6 Argelander-Institut für Astronomie, Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany Received 11 September 2016 / Accepted 1 January 2017 ABSTRACT Most massive stars, the progenitors of core-collapse supernovae, are in close binary systems and may interact with their companion through mass transfer or merging. We undertake a population synthesis study to compute the delay-time distribution of core-collapse supernovae, that is, the supernova rate versus time following a starburst, taking into account binary interactions. We test the systematic robustness of our results by running various simulations to account for the uncertainties in our standard assumptions. We find that +9 a significant fraction, 15−8%, of core-collapse supernovae are “late”, that is, they occur 50–200 Myr after birth, when all massive single stars have already exploded. -
Rotating Wolf-Rayet Stars in a Post RSG/LBV Phase an Evolutionary Channel Towards Long-Duration Grbs?
A&A 547, A83 (2012) Astronomy DOI: 10.1051/0004-6361/201118664 & c ESO 2012 Astrophysics Rotating Wolf-Rayet stars in a post RSG/LBV phase An evolutionary channel towards long-duration GRBs? G. Gräfener1,J.S.Vink1, T. J. Harries2, and N. Langer3 1 Armagh Observatory, College Hill, Armagh BT61 9DG, UK 2 School of Physics and Astronomy, University of Exeter, Stocker Rd, Exeter EX4 4QL, UK 3 Argelander-Institut für Astronomie der Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany Received 16 December 2011 / Accepted 3 October 2012 ABSTRACT Context. Wolf-Rayet (WR) stars with fast rotating cores are thought to be the direct progenitors of long-duration gamma-ray bursts (LGRBs). A well accepted evolutionary channel towards LGRBs is chemically-homogeneous evolution at low metallicities, which completely avoids a red supergiant (RSG), or luminous blue variable (LBV) phase. On the other hand, strong absorption features with velocities of several hundred km s−1 have been found in some LGRB afterglow spectra (GRB 020813 and GRB 021004), which have been attributed to dense circumstellar (CS) material that has been ejected in a previous RSG or LBV phase, and is interacting with a fast WR-type stellar wind. Aims. Here we investigate the properties of Galactic WR stars and their environment to identify similar evolutionary channels that may lead to the formation of LGRBs. Methods. We compile available information on the spectropolarimetric properties of 29 WR stars, the presence of CS ejecta for 172 WR stars, and the CS velocities in the environment of 34 WR stars in the Galaxy. -
PSR J1740-3052: a Pulsar with a Massive Companion
Haverford College Haverford Scholarship Faculty Publications Physics 2001 PSR J1740-3052: a Pulsar with a Massive Companion I. H. Stairs R. N. Manchester A. G. Lyne V. M. Kaspi Fronefield Crawford Haverford College, [email protected] Follow this and additional works at: https://scholarship.haverford.edu/physics_facpubs Repository Citation "PSR J1740-3052: a Pulsar with a Massive Companion" I. H. Stairs, R. N. Manchester, A. G. Lyne, V. M. Kaspi, F. Camilo, J. F. Bell, N. D'Amico, M. Kramer, F. Crawford, D. J. Morris, A. Possenti, N. P. F. McKay, S. L. Lumsden, L. E. Tacconi-Garman, R. D. Cannon, N. C. Hambly, & P. R. Wood, Monthly Notices of the Royal Astronomical Society, 325, 979 (2001). This Journal Article is brought to you for free and open access by the Physics at Haverford Scholarship. It has been accepted for inclusion in Faculty Publications by an authorized administrator of Haverford Scholarship. For more information, please contact [email protected]. Mon. Not. R. Astron. Soc. 325, 979–988 (2001) PSR J174023052: a pulsar with a massive companion I. H. Stairs,1,2P R. N. Manchester,3 A. G. Lyne,1 V. M. Kaspi,4† F. Camilo,5 J. F. Bell,3 N. D’Amico,6,7 M. Kramer,1 F. Crawford,8‡ D. J. Morris,1 A. Possenti,6 N. P. F. McKay,1 S. L. Lumsden,9 L. E. Tacconi-Garman,10 R. D. Cannon,11 N. C. Hambly12 and P. R. Wood13 1University of Manchester, Jodrell Bank Observatory, Macclesfield, Cheshire SK11 9DL 2National Radio Astronomy Observatory, PO Box 2, Green Bank, WV 24944, USA 3Australia Telescope National Facility, CSIRO, PO Box 76, Epping, NSW 1710, Australia 4Physics Department, McGill University, 3600 University Street, Montreal, Quebec, H3A 2T8, Canada 5Columbia Astrophysics Laboratory, Columbia University, 550 W. -
Regulus March-April 1991
REGULUS MARCH-APRIL 1991 NEWSLETTER OF THE KINGSTON CENTRE OF THE ROYAL ASTRONOMICAL SOCIETY OF CANADA OFFICERS AND EXECUTIVE COUNCIL HONORARY PRESIDENT.............. David Levy (000) 000-0000 PRESIDENT....................... Ian Levstein (000) 000-0000 VICE PRESIDENT.................. Victor Smida (000) 000-0000 SECRETARY....................... Kimberley Hay (000) 000-0000 TREASURER....................... Peter Kirk (000) 000-0000 LIBRARIAN....................... David Stokes (000) 000-0000 NEWSLETTER...................... Bill Broderick (000) 000-0000 NATIONAL COUNCIL REP............ Leo Enright (000) 000-0000 ALTERNATE N.C. REP.............. Walter MacDonald (000) 000-0000 COMMITTEES EDUCATION....................... Denise Sabatini (000) 000-0000 PUBLICITY....................... Bill Broderick (000) 000-0000 OBSERVING....................... Chris Collin (000) 000-0000 ASTRONOMY DAY................... Stan Hanna (000) 000-0000 Peggy Torney (000) 000-0000 UPCOMING MEETINGS AND EVENTS Regular Meetings of the Kingston Centre, RASC are held on the second Friday of each month at 8 p.m., in Room D-216, MacIntosh-Corry Hall, Queen’s University. Non—members are welcome. Executive meetings are at 7:30 p.m. Fri., March 8 Regular Meeting Peggy Torney, Review of "Voyage Through the Universe" Film, "To Boldly Go...", the Voyager Mission Thurs., March 28 Special Meeting Alister Ling, "Deep Sky Observing" Fri., April 12 Regular Meeting Ian Levstein, "The Surface is Fine and Powdery” Sat., April 20 ASTRONOMY DAY -- Mall Displays, etc. Sat., May 4 NFCAAA SPRING MEETING -- See information inside IN THIS ISSUE Page Message From The President................................................ 2 Holleford Meteorite Crater Tour........................................... 2 An Opportunity to State Our Opposition to Light Pollution................. 3 Report of the National Council Meeting of February 2, 1991................ 4 Observations of Mars During November, 1990................................ 6 Astro Jumble, Hunour, Etc................................................ -