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NASA's Goddard Space Flight Center Laboratory for High Energy
1 NASA’s Goddard Space Flight Center Laboratory for High Energy Astrophysics Greenbelt, Maryland 20771 @S0002-7537~99!00301-7# This report covers the period from July 1, 1997 to June 30, Toshiaki Takeshima, Jane Turner, Ken Watanabe, Laura 1998. Whitlock, and Tahir Yaqoob. This Laboratory’s scientific research is directed toward The following investigators are University of Maryland experimental and theoretical research in the areas of X-ray, Scientists: Drs. Keith Arnaud, Manuel Bautista, Wan Chen, gamma-ray, and cosmic-ray astrophysics. The range of inter- Fred Finkbeiner, Keith Gendreau, Una Hwang, Michael Loe- ests of the scientists includes the Sun and the solar system, wenstein, Greg Madejski, F. Scott Porter, Ian Richardson, stellar objects, binary systems, neutron stars, black holes, the Caleb Scharf, Michael Stark, and Azita Valinia. interstellar medium, normal and active galaxies, galaxy clus- Visiting scientists from other institutions: Drs. Vadim ters, cosmic-ray particles, and the extragalactic background Arefiev ~IKI!, Hilary Cane ~U. Tasmania!, Peter Gonthier radiation. Scientists and engineers in the Laboratory also ~Hope College!, Thomas Hams ~U. Seigen!, Donald Kniffen serve the scientific community, including project support ~Hampden-Sydney College!, Benzion Kozlovsky ~U. Tel such as acting as project scientists and providing technical Aviv!, Richard Kroeger ~NRL!, Hideyo Kunieda ~Nagoya assistance to various space missions. Also at any one time, U.!, Eugene Loh ~U. Utah!, Masaki Mori ~Miyagi U.!, Rob- there are typically between twelve and eighteen graduate stu- ert Nemiroff ~Mich. Tech. U.!, Hagai Netzer ~U. Tel Aviv!, dents involved in Ph.D. research work in this Laboratory. Yasushi Ogasaka ~JSPS!, Lev Titarchuk ~George Mason U.!, Currently these are graduate students from Catholic U., Stan- Alan Tylka ~NRL!, Robert Warwick ~U. -
Whole Earth Telescope Observations of AM Canum Venaticorum – Discoseismology at Last
Astron. Astrophys. 332, 939–957 (1998) ASTRONOMY AND ASTROPHYSICS Whole Earth Telescope observations of AM Canum Venaticorum – discoseismology at last J.-E. Solheim1;14, J.L. Provencal2;15, P.A. Bradley2;16, G. Vauclair3, M.A. Barstow4, S.O. Kepler5, G. Fontaine6, A.D. Grauer7, D.E. Winget2, T.M.K. Marar8, E.M. Leibowitz9, P.-I. Emanuelsen1, M. Chevreton10, N. Dolez3, A. Kanaan5, P. Bergeron6, C.F. Claver2;17, J.C. Clemens2;18, S.J. Kleinman2, B.P. Hine12, S. Seetha8, B.N. Ashoka8, T. Mazeh9, A.E. Sansom4;19, R.W. Tweedy4, E.G. Meistasˇ 11;13, A. Bruvold1, and C.M. Massacand1 1 Nordlysobservatoriet, Institutt for Fysikk, Universitetet i Tromsø, N-9037 Tromsø, Norway 2 McDonald Observatory and Department of Astronomy, The University of Texas at Austin, Austin, TX 78712, USA 3 Observatoire Midi–Pyrenees, 14 Avenue E. Belin, F-31400 Toulouse, France 4 Department of Physics and Astronomy, University of Leicester, Leicester, LE1 7RH, UK 5 Instituto de Fisica, Universidade Federal do Rio Grande do Sul, 91500-970 Porto Alegre - RS, Brazil 6 Department de Physique, Universite´ de Montreal,´ C.P. 6128, Succ A., Montreal,´ PQ H3C 3J7, Canada 7 Department of Physics and Astronomy, University of Arkansas, 2801 S. University Ave, Little Rock, AR 72204, USA 8 Technical Physics Division, ISRO Satelite Centre, Airport Rd, Bangalore, 560 017 India 9 University of Tel Aviv, Department of Physics and Astronomy, Ramat Aviv, Tel Aviv 69978, Israel 10 Observatoire de Paris-Meudon, F-92195 Meudon Principal Cedex, France 11 Institute of Material Research and Applied Sciences, Vilnius University, Ciurlionio 29, Vilnius 2009, Lithuania 12 NASA Ames Research Center, M.S. -
1000 Cataclysmic Variables from the Catalina Real-Time Transient Survey
MNRAS 443, 3174–3207 (2014) doi:10.1093/mnras/stu1377 1000 cataclysmic variables from the Catalina Real-time Transient Survey E. Breedt,1‹ B. T. Gansicke,¨ 1 A. J. Drake,2 P. Rodr´ıguez-Gil,3,4 S. G. Parsons,5 T. R. Marsh,1 P. Szkody,6 M. R. Schreiber5 and S. G. Djorgovski2 1Department of Physics, University of Warwick, Coventry, CV4 7AL, UK 2California Institute of Technology, 1200 E. California Blvd, CA 91225, USA 3Instituto de Astrof´ısica de Canarias, V´ıa Lactea´ s/n, La Laguna, E-38205, Santa Cruz de Tenerife, Spain 4Departamento de Astrof´ısica, Universidad de La Laguna, La Laguna, E-38206, Santa Cruz de Tenerife, Spain 5Instituto de F´ısica y Astronom´ıa, Universidad de Valpara´ıso, Avenida Gran Bretana 1111, 2360102 Valpara´ıso, Chile 6Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195-1580, USA Downloaded from Accepted 2014 July 6. Received 2014 July 5; in original form 2014 May 13 ABSTRACT Over six years of operation, the Catalina Real-time Transient Survey (CRTS) has identified http://mnras.oxfordjournals.org/ 1043 cataclysmic variable (CV) candidates – the largest sample of CVs from a single survey to date. Here, we provide spectroscopic identification of 85 systems fainter than g ≥ 19, including three AM Canum Venaticorum binaries, one helium-enriched CV, one polar and one new eclipsing CV. We analyse the outburst properties of the full sample and show that it contains a large fraction of low-accretion-rate CVs with long outburst recurrence times. We argue that most of the high-accretion-rate dwarf novae in the survey footprint have already been found and that future CRTS discoveries will be mostly low-accretion-rate systems. -
Superwasp Observations of Long Timescale Photometric Variations in Cataclysmic Variables
A&A 514, A30 (2010) Astronomy DOI: 10.1051/0004-6361/200912650 & c ESO 2010 Astrophysics SuperWASP observations of long timescale photometric variations in cataclysmic variables N. L. Thomas1,A.J.Norton1, D. Pollacco2,R.G.West3,P.J.Wheatley4, B. Enoch5, and W. I. Clarkson6 1 Department of Physics and Astronomy, The Open University, Milton Keynes MK7 6AA, UK e-mail: [email protected] 2 Astrophysics Research Centre, School of Mathematics and Physics, Queen’s University, University Road, Belfast BT7 1NN, UK 3 Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK 4 Department of Physics, University of Warwick, Coventry CV4 7AL, UK 5 SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St. Andrews, Fife KY16 9SS, UK 6 STScI, 3700 San Martin Drive, Baltimore, MD 21218, USA Received 7 June 2009 / Accepted 26 January 2010 ABSTRACT Aims. We investigated whether the predictions and results of Stanishev et al. (2002, A&A, 394, 625) concerning a possible relation- ship between eclipse depths in PX And and its retrograde disc precession phase, could be confirmed in long term observations made by SuperWASP. In addition, two further CVs (DQ Her and V795 Her) in the same SuperWASP data set were investigated to see whether evidence of superhump periods and disc precession periods were present and what other, if any, long term periods could be detected. Methods. Long term photometry of PX And, V795 Her and DQ Her was carried out and Lomb-Scargle periodogram analysis under- taken on the resulting light curves. For the two eclipsing CVs, PX And and DQ Her, we analysed the potential variations in the depth of the eclipse with cycle number. -
Arxiv:1810.09864V2 [Astro-Ph.SR] 6 Nov 2018
Manuscript for Revista Mexicana de Astronomía y Astrofísica (2007) EXTENSIVE PHOTOMETRY OF V1838 AQL DURING THE 2013 SUPEROUTBURST J. Echevarría1, E. de Miguel2, J. V. Hernández Santisteban3, R. Michel4, R. Costero1, L. J. Sánchez1, A. Ruelas-Mayorga1, J. Olivares5, D. González-Buitrago6, J.L. Jones7, A. Oskanen8, W. Goff9, J. Ulowetz10, G. Bolt11, R. Sabo12, F.-J Hambsch13, D. Slauson14, and W. Stein15 Draft version: September 6, 2021 RESUMEN Presentamos un estudio fotométrico detallado de la super-erupción de V1838 Aql, una variable cataclísmica recientemente descubierta, desde el máx- imo en 2013 hasta su regreso al mínimo. Examinamos en detalle la evolución de los superhumps. Determinamos el período orbital Porb = 0:05698(9) d a partir de la periodicidad de los superhumps tempranos. Comparando los períodos de superhumps en las etapas A y B con el valor del período orbital, derivamos un valor del cambio en el período orbital de = 0:024(2) y un cociente de masa para el sistema de q = 0:10(1). Sugerimos que V1838 Aql se está acercando al mínimo período orbital, por lo que la secundaria sería una estrella de baja masa y no un objeto sub-estelar. ABSTRACT We present an in-depth photometric study of the 2013 superoutburst of the recently discovered cataclysmic variable V1838 Aql and subsequent pho- tometry near its quiescent state. A careful examination of the development of the superhumps is presented. Our best determination of the orbital period is Porb = 0:05698(9) days, based on the periodicity of early superhumps. Com- paring the superhump periods at stages A and B with the early superhump 1Instituto de Astronomía, Universidad Nacional Autónoma de México, Apartado Postal 70-264, Ciudad Universitaria, México D.F., C.P. -
SAS-2019 the Symposium on Telescope Science
Proceedings for the 38th Annual Conference of the Society for Astronomical Sciences SAS-2019 The Symposium on Telescope Science Joint Meeting with the Center for Backyard Astrophysics Editors: Robert K. Buchheim Robert M. Gill Wayne Green John C. Martin John Menke Robert Stephens May, 2019 Ontario, CA i Disclaimer The acceptance of a paper for the SAS Proceedings does not imply nor should it be inferred as an endorsement by the Society for Astronomical Sciences of any product, service, method, or results mentioned in the paper. The opinions expressed are those of the authors and may not reflect those of the Society for Astronomical Sciences, its members, or symposium Sponsors Published by the Society for Astronomical Sciences, Inc. Rancho Cucamonga, CA First printing: May 2019 Photo Credits: Front Cover: NGC 2024 (Flame Nebula) and B33 (Horsehead Nebula) Alson Wong, Center for Solar System Studies Back Cover: SA-200 Grism spectrum of Wolf-Rayet star HD214419 Forrest Sims, Desert Celestial Observatory ii TABLE OF CONTENTS PREFACE v SYMPOSIUM SPONSORS vi SYMPOSIUM SCHEDULE viii PRESENTATION PAPERS Robert D. Stephens, Brian D. Warner THE SEARCH FOR VERY WIDE BINARY ASTEROIDS 1 Tom Polakis LESSONS LEARNED DURING THREE YEARS OF ASTEROID PHOTOMETRY 7 David Boyd SUDDEN CHANGE IN THE ORBITAL PERIOD OF HS 2325+8205 15 Tom Kaye EXOPLANET DETECTION USING BRUTE FORCE TECHNIQUES 21 Joe Patterson, et al FORTY YEARS OF AM CANUM VENATICORIUM 25 Robert Denny ASCOM – NOT JUST FOR WINDOWS ANY MORE 31 Kalee Tock HIGH ALTITUDE BALLOONING 33 William Rust MINIMIZING DISTORTION IN TIME EXPOSED CELESTIAL IMAGES 43 James Synge PROJECT PANOPTES 49 Steve Conard, et al THE USE OF FIXED OBSERVATORIES FOR FAINT HIGH VALUE OCCULTATIONS 51 John Martin, Logan Kimball UPDATE ON THE M31 AND M33 LUMINOUS STARS SURVEY 53 John Morris CURRENT STATUS OF “VISUAL” COMET PHOTOMETRY 55 Joe Patterson, et al ASASSN-18EY = MAXIJ1820+070 = “MAXIE”: KING OF THE BLACK HOLE 61 SUPERHUMPS Richard Berry IMAGING THE MOON AT THERMAL INFRARED WAVELENGTHS 67 iii Jerrold L. -
Case 20-32299-KLP Doc 208 Filed 06/01/20 Entered 06/01/20 16
Case 20-32299-KLP Doc 208 Filed 06/01/20 Entered 06/01/20 16:57:32 Desc Main Document Page 1 of 137 Case 20-32299-KLP Doc 208 Filed 06/01/20 Entered 06/01/20 16:57:32 Desc Main Document Page 2 of 137 Exhibit A Case 20-32299-KLP Doc 208 Filed 06/01/20 Entered 06/01/20 16:57:32 Desc Main Document Page 3 of 137 Exhibit A1 Served via Overnight Mail Name Attention Address 1 Address 2 City State Zip Country Aastha Broadcasting Network Limited Attn: Legal Unit213 MezzanineFl Morya LandMark1 Off Link Road, Andheri (West) Mumbai 400053 IN Abs Global LTD Attn: Legal O'Hara House 3 Bermudiana Road Hamilton HM08 BM Abs-Cbn Global Limited Attn: Legal Mother Ignacia Quezon City Manila PH Aditya Jain S/O Sudhir Kumar Jain Attn: Legal 12, Printing Press Area behind Punjab Kesari Wazirpur Delhi 110035 IN AdminNacinl TelecomunicacionUruguay Complejo Torre De Telecomuniciones Guatemala 1075. Nivel 22 HojaDeEntrada 1000007292 5000009660 Montevideo CP 11800 UY Advert Bereau Company Limited Attn: Legal East Legon Ars Obojo Road Asafoatse Accra GH Africa Digital Network Limited c/o Nation Media Group Nation Centre 7th Floor Kimathi St PO Box 28753-00100 Nairobi KE Africa Media Group Limited Attn: Legal Jamhuri/Zaramo Streets Dar Es Salaam TZ Africa Mobile Network Communication Attn: Legal 2 Jide Close, Idimu Council Alimosho Lagos NG Africa Mobile Networks Cameroon Attn: Legal 131Rue1221 Entree Des Hydrocarbures Derriere Star Land Hotel Bonapriso-Douala Douala CM Africa Mobile Networks Cameroon Attn: Legal BP12153 Bonapriso Douala CM Africa Mobile Networks Gb, -
Constelações – Volume 8
Coleção Os Mensageiros das Estrelas: Constelações – volume 8 Constelações de Maio Organizador Paulo Henrique Colonese Autores Leonardo Pereira de Castro Rafaela Ribeiro da Silva Ilustrador Caio Lopes do Nascimento Baldi Fiocruz-COC 2021 Coleção Os Mensageiros das Estrelas: Constelações – volume 8 Constelações de Maio Organizador Paulo Henrique Colonese Autores Leonardo Pereira de Castro Rafaela Ribeiro da Silva Ilustrador Caio Lopes do Nascimento Baldi Fiocruz-COC 2021 ii Licença de Uso O conteúdo dessa obra, exceto quando indicado outra licença, está disponível sob a Licença Creative Commons, Atribuição-Não Comercial-Compartilha Igual 4.0. FUNDAÇÃO OSWALDO CRUZ Presidente Nísia Trindade Lima Diretor da Casa de Oswaldo Cruz Paulo Roberto Elian dos Santos Chefe do Museu da Vida Alessandro Machado Franco Batista TECNOLOGIAS SERVIÇO DE ITINERÂNCIA Stellarium, OBS Studio, VideoScribe, Canva CIÊNCIA MÓVEL Paulo Henrique Colonese (Coordenação) Ana Carolina de Souza Gonzalez Fernanda Marcelly de Gondra França REVISÃO CADERNO DE CONTEÚDOS Flávia Souza Lima Paulo Henrique Colonese Lais Lacerda Viana Marta Fabíola do Valle G. Mayrink APOIO ADMINISTRATIVO (Coordenação) Fábio Pimentel Paulo Henrique Colonese Rodolfo de Oliveira Zimmer MÍDIAS E DIVULGAÇÃO Julianne Gouveia CONCEPÇÃO E DESENVOLVIMENTO Melissa Raquel Faria Silva Jackson Almeida de Farias Renata Bohrer Leonardo Pereira de Castro Renata Maria B. Fontanetto (Coordenação) Luiz Gustavo Barcellos Inácio (in memoriam) Paulo Henrique Colonese (Coordenação) CAPTAÇÃO DE RECURSOS Rafaela Ribeiro da Silva Escritório de Captação da Fiocruz Willian Alves Pereira Willian Vieira de Abreu GESTÃO CULTURAL Sociedade de Promoção da Casa de Oswaldo DESIGN GRÁFICO E ILUSTRAÇÃO Cruz Caio Lopes do Nascimento Baldi Biblioteca de Educação e Divulgação Científica Iloni Seibel C756 Constelações de maio [recurso eletrônico] / Organizador: Paulo Henrique Colonese. -
Arxiv:2001.10147V1
Magnetic fields in isolated and interacting white dwarfs Lilia Ferrario1 and Dayal Wickramasinghe2 Mathematical Sciences Institute, The Australian National University, Canberra, ACT 2601, Australia Adela Kawka3 International Centre for Radio Astronomy Research, Curtin University, Perth, WA 6102, Australia Abstract The magnetic white dwarfs (MWDs) are found either isolated or in inter- acting binaries. The isolated MWDs divide into two groups: a high field group (105 − 109 G) comprising some 13 ± 4% of all white dwarfs (WDs), and a low field group (B < 105 G) whose incidence is currently under investigation. The situation may be similar in magnetic binaries because the bright accretion discs in low field systems hide the photosphere of their WDs thus preventing the study of their magnetic fields’ strength and structure. Considerable research has been devoted to the vexed question on the origin of magnetic fields. One hypothesis is that WD magnetic fields are of fossil origin, that is, their progenitors are the magnetic main-sequence Ap/Bp stars and magnetic flux is conserved during their evolution. The other hypothesis is that magnetic fields arise from binary interaction, through differential rotation, during common envelope evolution. If the two stars merge the end product is a single high-field MWD. If close binaries survive and the primary develops a strong field, they may later evolve into the arXiv:2001.10147v1 [astro-ph.SR] 28 Jan 2020 magnetic cataclysmic variables (MCVs). The recently discovered population of hot, carbon-rich WDs exhibiting an incidence of magnetism of up to about 70% and a variability from a few minutes to a couple of days may support the [email protected] [email protected] [email protected] Preprint submitted to Journal of LATEX Templates January 29, 2020 merging binary hypothesis. -
Determination of Stellar Parameters for M-Dwarf Stars: the NIR Approach
Determination of stellar parameters for M-dwarf stars: the NIR approach by Daniel Thaagaard Andreasen A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Graduate Department of Departamento de Fisica e Astronomia University of Porto c Copyright 2017 by Daniel Thaagaard Andreasen Dedication To Linnea, Henriette, Rico, and Else For always supporting me ii Acknowledgements When doing a PhD it is important to remember it is more a team effort than the work of an individual. This is something I learned quickly during the last four years. Therefore there are several people I would like to thank. First and most importantly are my two supervisors, Sérgio and Nuno. They were after me in the beginning of my studies because I was too shy to ask for help; something that I quickly learned I needed to do. They always had their door open for me and all my small questions. It goes without saying that I am thankful for all their guidance during my studies. However, what I am most thankful for is the freedom I have had to explorer paths and ideas on my own, and with them safely on the sideline. This sometimes led to failures and dead ends, but it make me grow as a researcher both by learning from my mistake, but also by prioritising my time. When I thank Sérgio and Nuno, my official supervisors, I also have to thank Elisa. She has been my third unofficial supervisor almost from the first day. Although she did not have any experience with NIR spectroscopy, she was never afraid of giving her opinion and trying to help. -
Patrick Moore's Practical Astronomy Series
Patrick Moore’s Practical Astronomy Series Other Titles in this Series Navigating the Night Sky Astronomy of the Milky Way How to Identify the Stars and The Observer’s Guide to the Constellations Southern/Northern Sky Parts 1 and 2 Guilherme de Almeida hardcover set Observing and Measuring Visual Mike Inglis Double Stars Astronomy of the Milky Way Bob Argyle (Ed.) Part 1: Observer’s Guide to the Observing Meteors, Comets, Supernovae Northern Sky and other transient Phenomena Mike Inglis Neil Bone Astronomy of the Milky Way Human Vision and The Night Sky Part 2: Observer’s Guide to the How to Improve Your Observing Skills Southern Sky Michael P. Borgia Mike Inglis How to Photograph the Moon and Planets Observing Comets with Your Digital Camera Nick James and Gerald North Tony Buick Telescopes and Techniques Practical Astrophotography An Introduction to Practical Astronomy Jeffrey R. Charles Chris Kitchin Pattern Asterisms Seeing Stars A New Way to Chart the Stars The Night Sky Through Small Telescopes John Chiravalle Chris Kitchin and Robert W. Forrest Deep Sky Observing Photo-guide to the Constellations The Astronomical Tourist A Self-Teaching Guide to Finding Your Steve R. Coe Way Around the Heavens Chris Kitchin Visual Astronomy in the Suburbs A Guide to Spectacular Viewing Solar Observing Techniques Antony Cooke Chris Kitchin Visual Astronomy Under Dark Skies How to Observe the Sun Safely A New Approach to Observing Deep Space Lee Macdonald Antony Cooke The Sun in Eclipse Real Astronomy with Small Telescopes Sir Patrick Moore and Michael Maunder Step-by-Step Activities for Discovery Transit Michael K. -
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Baltic Astronomy, vol. 19, 95{110, 2010 CHEMICAL COMPOSITION OF THE RS CVn-TYPE STAR LAMBDA ANDROMEDAE G. Tautvaiˇsien_e1, G. Bariseviˇcius1, S. Berdyugina2, Y. Chorniy1 and I. Ilyin3 1 Institute of Theoretical Physics and Astronomy, Vilnius University, Goˇstauto12, Vilnius LT-01108, Lithuania 2 Kiepenheuer Institut f¨urSonnenphysik, Sch¨oneckstrasse 6, Freiburg D-79104, Germany 3 Astrophysical Institute Potsdam, An der Sternwarte 16, Potsdam D-14482, Germany Received: 2010 June 8; accepted: 2010 June 15 Abstract. Photospheric parameters and chemical composition are deter- mined for the single-lined chromospherically active RS CVn-type star λ And (HD 222107). From the high resolution spectra obtained on the Nordic Optical Telescope, abundances of 22 chemical elements and isotopes, including such key elements as 12C, 13C, N and O, were investigated. The differential line analysis with the MARCS model atmospheres gives Teff = 4830 K, log g = 2.8, [Fe/H] = {0.53, [C/Fe] = 0.09, [N/Fe] = 0.35, [O/Fe] = 0.45, C/N = 2.21, 12C/13C = 14. The 12C/13C ratio for a star of the RS CVn-type is determined for the first time, and its low value gives a hint that extra-mixing processes may start acting in low-mass chromospherically active stars below the bump of the luminosity function of red giants. Key words: stars: RS CVn binaries, abundances { stars: individual (λ And = HD 222107) 1. INTRODUCTION The RS CVn-type stars have been studied thoroughly since 1965 when their peculiar light curves were detected (Rodon´o1965; Chisari & Lacona 1965) and a new distinct class of binaries was named (Olivier 1974; Hall 1976).