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Fine-Structure Feii and Siii Absorption in the Spectrum of GRB 051111
Draft version November 11, 2018 Preprint typeset using LATEX style emulateapj Fine-Structure Fe II and Si II Absorption in the Spectrum of GRB051111: Implications for the Burst Environment E. Berger1,2,3, B. E. Penprase4, D. B. Fox5, S. R. Kulkarni6, G. Hill7, B. Schaefer7, and M. Reed7 Draft version November 11, 2018 ABSTRACT We present an analysis of fine-structure transitions of Fe II and Si II detected in a high-resolution optical spectrum of the afterglow of GRB051111 (z =1.54948). The fine-structure absorption features arising from Fe II* to Fe II****, as well as Si II*, are confined to a narrow velocity structure extending over ±30 km s−1, which we interpret as the burst local environment, most likely a star forming region. We investigate two scenarios for the excitation of the fine-structure levels by collisions with electrons and radiative pumping by an infra-red or ultra-violet radiation field produced by intense star formation in the GRB environment, or by the GRB afterglow itself. We find that the conditions required for collisional excitation of Fe II fine-structure states cannot be easily reconciled with the relatively weak Si II* absorption. Radiative pumping by either IR or UV emission requires > 103 massive hot OB stars within a compact star-forming region a few pc in size, and in the case of IR pumping a large dust content. On the other hand, it is possible that the GRB itself provides the source of IR and/or UV radiation, in which case we estimate that the excitation takes place at a distance of ∼ 10 − 20 pc from the burst. -
Eclipsing Systems with Pulsating Components (Types Β Cep, Δ Sct, Γ Dor Or Red Giant) in the Era of High-Accuracy Space Data
galaxies Review Eclipsing Systems with Pulsating Components (Types b Cep, d Sct, g Dor or Red Giant) in the Era of High-Accuracy Space Data Patricia Lampens Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium; [email protected] Abstract: Eclipsing systems are essential objects for understanding the properties of stars and stellar systems. Eclipsing systems with pulsating components are furthermore advantageous because they provide accurate constraints on the component properties, as well as a complementary method for pulsation mode determination, crucial for precise asteroseismology. The outcome of space missions aiming at delivering high-accuracy light curves for many thousands of stars in search of planetary systems has also generated new insights in the field of variable stars and revived the interest of binary systems in general. The detection of eclipsing systems with pulsating components has particularly benefitted from this, and progress in this field is growing fast. In this review, we showcase some of the recent results obtained from studies of eclipsing systems with pulsating components based on data acquired by the space missions Kepler or TESS. We consider different system configurations including semi-detached eclipsing binaries in (near-)circular orbits, a (near-)circular and non-synchronized eclipsing binary with a chemically peculiar component, eclipsing binaries showing the heartbeat phenomenon, as well as detached, eccentric double-lined systems. All display one or more pulsating component(s). Among the great variety of known classes of pulsating stars, we discuss unevolved or slightly evolved pulsators of spectral type B, A or F and red giants with solar-like oscillations. Some systems exhibit additional phenomena such as tidal effects, angular momentum transfer, (occasional) Citation: Lampens, P. -
Macrocosmo Nº33
HA MAIS DE DOIS ANOS DIFUNDINDO A ASTRONOMIA EM LÍNGUA PORTUGUESA K Y . v HE iniacroCOsmo.com SN 1808-0731 Ano III - Edição n° 33 - Agosto de 2006 * t i •■•'• bSÈlÈWW-'^Sif J fé . ’ ' w s » ws» ■ ' v> í- < • , -N V Í ’\ * ' "fc i 1 7 í l ! - 4 'T\ i V ■ }'- ■t i' ' % r ! ■ 7 ji; ■ 'Í t, ■ ,T $ -f . 3 j i A 'A ! : 1 l 4/ í o dia que o ceu explodiu! t \ Constelação de Andrômeda - Parte II Desnudando a princesa acorrentada £ Dicas Digitais: Softwares e afins, ATM, cursos online e publicações eletrônicas revista macroCOSMO .com Ano III - Edição n° 33 - Agosto de I2006 Editorial Além da órbita de Marte está o cinturão de asteróides, uma região povoada com Redação o material que restou da formação do Sistema Solar. Longe de serem chamados como simples pedras espaciais, os asteróides são objetos rochosos e/ou metálicos, [email protected] sem atmosfera, que estão em órbita do Sol, mas são pequenos demais para serem considerados como planetas. Até agora já foram descobertos mais de 70 Diretor Editor Chefe mil asteróides, a maior parte situados no cinturão de asteróides entre as órbitas Hemerson Brandão de Marte e Júpiter. [email protected] Além desse cinturão podemos encontrar pequenos grupos de asteróides isolados chamados de Troianos que compartilham a mesma órbita de Júpiter. Existem Editora Científica também aqueles que possuem órbitas livres, como é o caso de Hidalgo, Apolo e Walkiria Schulz Ícaro. [email protected] Quando um desses asteróides cruza a nossa órbita temos as crateras de impacto. A maior cratera visível de nosso planeta é a Meteor Crater, com cerca de 1 km de Diagramadores diâmetro e 600 metros de profundidade. -
Hydrogen Subordinate Line Emission at the Epoch of Cosmological Recombination M
Astronomy Reports, Vol. 47, No. 9, 2003, pp. 709–716. Translated from Astronomicheski˘ı Zhurnal, Vol. 80, No. 9, 2003, pp. 771–779. Original Russian Text Copyright c 2003 by Burgin. Hydrogen Subordinate Line Emission at the Epoch of Cosmological Recombination M. S. Burgin Astro Space Center, Lebedev Physical Institute, Russian Academy of Sciences, Profsoyuznaya ul. 84/32, Moscow, 117997 Russia Received December 10, 2002; in final form, March 14, 2003 Abstract—The balance equations for the quasi-stationary recombination of hydrogen plasma in a black- body radiation field are solved. The deviations of the excited level populations from equilibrium are computed and the rates of uncompensated line transitions determined. The expressions obtained are stable for computations of arbitrarily small deviations from equilibrium. The average number of photons emitted in hydrogen lines per irreversible recombination is computed for plasma parameters corresponding to the epoch of cosmological recombination. c 2003 MAIK “Nauka/Interperiodica”. 1. INTRODUCTION of this decay is responsible for the appreciable differ- When the cosmological expansion of the Universe ence between the actual degree of ionization and the lowered the temperature sufficiently, the initially ion- value correspondingto the Saha –Boltzmann equi- ized hydrogen recombined. According to [1, 2], an librium. A detailed analysis of processes affectingthe appreciable fraction of the photons emitted at that recombination rate and computations of the temporal time in subordinate lines survive to the present, lead- behavior of the degree of ionization for various sce- ingto the appearance of spectral lines in the cosmic narios for the cosmological expansion are presented background (relict) radiation. Measurements of the in [5, 6]. -
The 2003-4 Multisite Photometric Campaign for the Beta Cephei And
Mon. Not. R. Astron. Soc. 000, 000–000 (0000) Printed 14 August 2018 (MN LATEX style file v2.2) The 2003-4 multisite photometric campaign for the β Cephei and eclipsing star 16 (EN) Lacertae with an Appendix on 2 Andromedae, the variable comparison star M. Jerzykiewicz,1⋆ G. Handler,2 J. Daszy´nska-Daszkiewicz,1 A. Pigulski,1 E. Poretti,3 E. Rodr´ıguez,4 P. J. Amado,4 Z. Ko laczkowski,1 K. Uytterhoeven,5,6 T. N. Dorokhova,7 N. I. Dorokhov,7 D. Lorenz,8 D. Zsuffa,9 S.-L. Kim,10 P.-O. Bourge,11 B. Acke,5 J. De Ridder,5 T. Verhoelst,5 R. Drummond,5 A. I. Movchan,7 J.-A. Lee,10 M. St¸e´slicki,12 J. Molenda-Zakowicz,˙ 1 R. Garrido,4 S.-H. Kim,10 G. Michalska,1 M. Papar´o,9 V. Antoci,8 C. Aerts5 1 Astronomical Institute of the Wroc law Univeristy, Kopernika 11, 51-622 Wroc law, Poland 2 Copernicus Astronomical Center, Bartycka 18, 00-716, Warsaw, Poland 3 INAF-Osservatorio Astronomico di Brera, Via Bianchi 46, 23807 Merate, Italy 4 Instituto de Astrofisica de Andalucia, C.S.I.C., Apdo. 3004, 18080 Granada, Spain 5 Instituut voor Sterrenkunde, K. U. Leuven, Celestijnenlaan 200B, B-3001 Leuven, Belgium 6 Mercator Telescope, Calle Alvarez de Abreu 70, 38700 Santa Cruz de La Palma, Spain 7 Astronomical Observatory of Odessa National University, Marazlievskaya, 1v, 65014 Odessa, Ukraine 8 Institut f¨ur Astronomie, Universit¨at Wien, T¨urkenschanzstrasse 17, A-1180 Wien, Austria 9 Konkoly Observatory, MTA CSFK, Konkoly Thege Mikl´os ´ut 15-17., 1121 Budapest, Hungary 10 Korea Astronomy and Space Science Institute, Daejeon, 305-348, Korea 11 Institut d’Astrophysique et de G´eophysique, Universit´e de Li`ege, all´ee du Six Aoˆut 17, 4000 Li`ege, Belgium 12 Space Research Centre, Polish Academy of Sciences, Solar Physics Division, ul. -
Biological Damage of Uv Radiation in Environments Of
BIOLOGICAL DAMAGE OF UV RADIATION IN ENVIRONMENTS OF F-TYPE STARS by SATOKO SATO Presented to the Faculty of the Graduate School of The University of Texas at Arlington in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY THE UNIVERSITY OF TEXAS AT ARLINGTON May 2014 Copyright c by Satoko Sato 2014 All Rights Reserved I dedicate this to my daughter Akari Y. Sato. Acknowledgements First of all, I would like to thank my supervising professor Dr. Manfred Cuntz. His advice on my research and academic life has always been invaluable. I would have given up the Ph.D. bound program without his encouragement and generous support as the supervising professor during a few difficult times in my life. I would like to thank Dr. Wei Chen, Dr. Yue Deng, Dr. Zdzislaw E. Musielak, and Dr. Sangwook Park for their interest in my research and for their time to serve in my committee. Next, I would like to acknowledge my research collaborators at University of Guanajuato, Cecilia M. Guerra Olvera, Dr. Dennis Jack, and Dr. Klaus-Peter Schr¨oder,for providing me the data of F-type evolutionary tracks and UV spectra. I would also like to express my deep gratitude to my parents, Hideki and Kumiko Yakushigawa, for their enormous support in many ways in my entire life, and to my sister, Tomoko Yakushigawa, for her constant encouragement to me. I am grateful to my husband, Makito Sato, and my daughter, Akari Y. Sato. Their presence always gives me strength. I am thankful to my parents-in-law, Hisao and Tsuguho Sato, and my grand-parents-in-law, Kanji and Ayako Momoi, for their financial support and prayers. -
Information Bulletin on Variable Stars
COMMISSIONS AND OF THE I A U INFORMATION BULLETIN ON VARIABLE STARS Nos April November EDITORS L SZABADOS K OLAH TECHNICAL EDITOR A HOLL TYPESETTING MB POCS ADMINISTRATION Zs KOVARI EDITORIAL BOARD E Budding HW Duerb eck EF Guinan P Harmanec chair D Kurtz KC Leung C Maceroni NN Samus advisor C Sterken advisor H BUDAPEST XI I Box HUNGARY URL httpwwwkonkolyhuIBVSIBVShtml HU ISSN 2 IBVS 4701 { 4800 COPYRIGHT NOTICE IBVS is published on b ehalf of the th and nd Commissions of the IAU by the Konkoly Observatory Budap est Hungary Individual issues could b e downloaded for scientic and educational purp oses free of charge Bibliographic information of the recent issues could b e entered to indexing sys tems No IBVS issues may b e stored in a public retrieval system in any form or by any means electronic or otherwise without the prior written p ermission of the publishers Prior written p ermission of the publishers is required for entering IBVS issues to an electronic indexing or bibliographic system to o IBVS 4701 { 4800 3 CONTENTS WOLFGANG MOSCHNER ENRIQUE GARCIAMELENDO GSC A New Variable in the Field of V Cassiop eiae :::::::::: JM GOMEZFORRELLAD E GARCIAMELENDO J GUARROFLO J NOMENTORRES J VIDALSAINZ Observations of Selected HIPPARCOS Variables ::::::::::::::::::::::::::: JM GOMEZFORRELLAD HD a New Low Amplitude Variable Star :::::::::::::::::::::::::: ME VAN DEN ANCKER AW VOLP MR PEREZ D DE WINTER NearIR Photometry and Optical Sp ectroscopy of the Herbig Ae Star AB Au rigae ::::::::::::::::::::::::::::::::::::::::::::::::::: -