DOCSLIB.ORG

Observation and Interpretation of the Cygnus X-1 System

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Observation and Interpretation of the Cygnus X-1 System OBSERVATION AND INTERPRETATION OF THE CYGNUS X-1 SYSTEM by ZORAN NINKOV M.Sc., Monash University, 1981 B.Sc.(Honours), University of Western Australia, 1978 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE STUDIES Department of Geophysics and Astronomy We accept this thesis as conforming to the req^r^o" standard THE UNIVERSITY OF BRITISH COLUMBIA July 1985 £ © Zoran Ninkov, 1985 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the The University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the Head of my Department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of Geophysics and Astronomy The University of British Columbia 2075 Wesbrook Place Vancouver, Canada V6T 1W5 Date: July 1985 ABSTRACT The results of a long term monitoring program on the massive X-ray binary Cygnus X-1, whose constituents are believed to consist of a normal 0 star primary and a black hole companion, are presented. Spectra of this system were collected between 1980 and 1984 using a Reticon detector. The resulting absorption line radial velocity (RV) curve is characteristic of a single line spectroscopic binary. These velocities were combined with those available in the literature to determine an orbital period of 5.59977 ± 0.00001 days. A P/P =* 10"5 day"1 was found from analysis of all available velocity measures. This change in the period is larger than that expected as a result of mass loss from the primary or from- models of the system in which large mass transfer rates occur between the components. A fit of the orbital motion of the primary to the RV curve gives a K = 75.0 ± 1 km/s and no significant eccentricity. The vsini of the primary was found, using the fourier transform technique, to be 94.3 km/sec. This is substantially smaller than the literature value of vsini = 140 km/sec. The value of the K and vsini allow the ratio m /m to be determined as p x * 2.0 . The equivalent width of H7 allows the absolute magnitude -ol the primary to be estimated at -6.5 ± 0.2 . A comparison of the spectrum of the primary to those of an array of standards allows the spectral type to be given as between 09.5 and 09.7 I . This spectral type is consistent with the absolute magnitude obtained and it is thus likely that the primary is a normal star of mass « 20 MQ. The mass of the secondary is therefore 10 ± 3 MQ. Measurement of the interstellar lines to obtain an independent E(B-V) reveals that the interstellar line strength per unit E(B-V) is lower than in any other direction in the sky. Stars for which velocity-excitation slopes and mass loss estimates, from UV line profile modeling and/or radio free-free emission measures, are available in the literature were collated. An empirical fit to this material allowed the mass loss rate for HDE 226868 (the primary of Cygnus X-1) to be estimated at 5.7 ± 2 x 10~6 M/year. The He II X4686 and Ha lines are found in emission. After removal of the contribution to the line profile from the primary the radial velocity curve of the residual He II X4686 line is found to have small scatter from a smooth fit ( ± 10 km/sec ) with no significant eccentricity. No sizeable variation in the K amplitude at different epochs was found contrary to a previous investigation and the origin of the emission is thus apparently fixed and stable. A phase lag of 130° is measured between the absorption and emission velocity curves and thus the simple interpretation of the emmision originating near the secondary can not be correct. The He II emission equivalent width, corrected for the underlying primary absorption, shows strong modulation (30%) over the 5.6 day orbital period. This variation is probably the result of the profile of the primary varying with which face of the star is directed towards the observer. During two separate observing sessions in 1982 the He II equivalent widths were found to be 40% and 15% larger than the mean of all other observations while still showing the same variation with orbital phase. Such a change has been seen once before and may be associated with transitions to the X-ray high state. The H7 and H/3 lines show a 20% variation on the 294 day X-ray period in the sense of largest equvalent widths at X-ray minimum ( 0 phase ). The Balmer lines are a composite of an absorption component from the primary and a weak emission component. This is best explained by variations in the outflow from the star, which is the source of both the emission component and the X-ray flux via accretion. Such variations may be the result of pulsation of the primary. The Ha line profile has been decomposed into three components; the absorption component from the primary, emission from a shell with an inner radius 1.4 times that of the primary, arid a component with properties similar to the He II X4686 line. The great width of the Ha line, previously explained as being the result of rotation of the disc, is instead shown to be the result of superposition of these components. The origin of the He II X4686 emission is explained by assuming that a stellar wind enhanced in the direction of the . secondary is completely ionized within a volume surrounding the secondary. The He II between the edge of this volume and the surface of the primary is enhanced as a result of X-ray heating and ionization. Model profiles appear in reasonable agreement with high dispersion spectra. The obvious explanation for the orbital variation in the He II line is that X-ray heating of the side of the primary facing the secondary produces a change in the effective temperature. Calculation of the size of this effect reveals that it is too small to explain the changes observed. X-ray observations made with EXOSAT with excellent time resolution allowed timing of the X-ray absorption features seen near orbital phase zero. Simultaneous X-ray spectra allowed an estimate of their column density as 2.0 x 1023 cm"2. Two scale lengths of dips were found of 10s and 1011 cm. These values are in good agreement with theoretical predictions for the sizes of inhomogeneties in high mass loss stellar winds. The location of the material producing the absorption dips was calculated as being * 4-8 R@ from the X-ray source. v Table of Contents Abstract ii Table of Contents vi List of Tables viii List of Figures x Acknowledgements xiv 1 . Introduction 1 1.1 Early History of X-ray Binaries 1 1.2 History of Cygnus X-1 6 2. Data Collection and Analysis 11 2.1 The Observations 11 2.2 The Reticon Detector 12 2.3 The Data Reduction 16 2.4 Problems with Darks ". 19 2.5 Cosmic Ray Events 23 2.6 The Data 36 2.7 Digital Subtraction 36 3. The Absorption Line Spectrum 48 3.1 Rationale for the Study 48 3.2 The Spectrum Itself 50 3.3 Equivalent Width Determination 58 3.4 The Spectral Type 64 3.5 The Rotational Velocity 80 3.6 The Radial Velocity Curve 92 3.7 Masses of the Components 131 3.8 E(B-V) and the Interstellar Lines 136 3.9 Mass Loss Rate 138 vi 3.10 Equivalent Width Variations 146 3.11 Line Halfwidth Variations 160 4. The Emission Line Spectrum 165 4.1 Rationale for the Study 165 4.2 Analysis of the He II 74686 Data 166 4.2.1 Finding a Good Reference Star 166 4.2.2 Correction of the He II Profiles 172 4.2.3 The CFHT He II 74686 Profiles 181 4.3 The He II Emission Radial Velocity Curve 181 4.4 Equivalent Width Measures 192 4.5 The Ha Data 199 4.6 The Ha Profile of the Primary 206 4.7 The Hydrogen Absorption Lines 216 5. Emission Mechanisms ..222 5.1 X-Ray heating of the Primary 222 5.2 Overflow onto the Secondary 223 5.3 Trailing Shock Model 231 5.4 Emission from the Disc 233 5.5 Enhanced Stellar Wind 234 5.6 The Model 238 5.7 Variation of He II Absorption Line 255 6. X-Ray Observations 266 7. Conclusions 281 Bibliography 285 Appendix A 30.2 vii List of Tables 1.01 Type I vs Type II X-ray System Characteristics 5 1.02 Observed Properties of the Cygnus X-1 System 8 2.01 Ret icon Systems 16 2.02 Details of occurrence of spikes 32 2.03 Details of observations of Cygnus X-1 37 2.04 Details of observations of Comparison Stars 40 3.01a Line List for Early Type Stars (blue) 56 3.01b Line List for Early Type Stars (Red) ....57 3.02 Standard Star Characteristics 67 3.03 Standard Star Ratios of Spectrally Sensitive Lines 78 3.04 Line weights for least squares fitting radial velocity curve and excitation potential' for line groups 97 3.05 Calculated velocities for spectra of HDE 226868 ....98 3.06 Fitted ?T? at different epochs ...123 3.07 Weights for least squares fitting radial velocity curve by year 130 3.08 Orbit Solution for Cygnus X-1 130 3.09 E(B-V) as determined from the Interstellar lines ..137 3.10 Mass loss rates from different techniques ...142 3.11 Normalized equivalent width variations with phase .158 3.12 Normalized phase variations of He I halfwidth 162 4.01 Line List for CFHT 169 4.02 Equivalent Widths for lines from CFHT Data 174 vi i i 4.03 He II X4686 emission radial velocities and equivalent widths ..187 4.04 Orbit parameters for He II X4686 emission radial velocity curve 191 4.05 He II X4686 equivalent widths and halfwidths as function of orbital phase 194 4.06 Equivalent Widths Binned on the 294 day Period ....217 5.01 Assumed Basic Parameters of Cygnus X-1 253 5.02
Load more

Recommended publications
  • Hard X-Ray Emission Clumps in the Γ-Cygni Supernova Remnant: the an INTEGRAL-ISGRI View To
    A&A 427, L21–L24 (2004) Astronomy DOI: 10.1051/0004-6361:200400089 & c ESO 2004 Astrophysics Editor Hard X-ray emission clumps in the γ-Cygni supernova remnant: the An INTEGRAL-ISGRI view to A. M. Bykov1, A. M. Krassilchtchikov1 , Yu. A. Uvarov1,H.Bloemen2,R.A.Chevalier3, M. Yu. Gustov1, W. Hermsen2,F.Lebrun4,T.A.Lozinskaya5,G.Rauw6,T.V.Smirnova7, S. J. Sturner8, J.-P. Swings6, R. Terrier4, and I. N. Toptygin1 Letter 1 A. F. Ioffe Institute for Physics and Technology, 26 Polytechnicheskaia, 194021 St. Petersburg, Russia e-mail: [email protected] 2 SRON National Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands 3 Department of Astronomy, University of Virginia, PO Box 3818, Charlottesville, VA 22903, USA 4 CEA – Saclay, DSM/DAPNIA/Service d’Astrophysique, 91191 Gif-sur-Yvette Cedex, France 5 Sternberg Astronomical Institute, Moscow State University, 13 Universitetskij, 119899 Moscow, Russia 6 Institut d’Astrophysique et de Géophysique, Université de Liège, Allée du 6 Août 17, Bât. B5c, 4000 Liège, Belgium 7 Astro Space Center of the Lebedev Physics Institute, 84/32 Profsoyuznaia, 117810 Moscow, Russia 8 NASA Goddard Space Flight Center, Code 661, Greenbelt, MD 20771, USA Received 22 September 2004 / Accepted 9 October 2004 Abstract. Spatially resolved images of the galactic supernova remnant G78.2+2.1 (γ-Cygni) in hard X-ray energy bands from 25 keV to 120 keV are obtained with the IBIS-ISGRI imager aboard the International Gamma-Ray Astrophysics Laboratory INTEGRAL. The images are dominated by localized clumps of about ten arcmin in size.
    [Show full text]
  • International Astronomical Union Commission 42 BIBLIOGRAPHY of CLOSE BINARIES No. 93
    International Astronomical Union Commission 42 BIBLIOGRAPHY OF CLOSE BINARIES No. 93 Editor-in-Chief: C.D. Scarfe Editors: H. Drechsel D.R. Faulkner E. Kilpio E. Lapasset Y. Nakamura P.G. Niarchos R.G. Samec E. Tamajo W. Van Hamme M. Wolf Material published by September 15, 2011 BCB issues are available via URL: http://www.konkoly.hu/IAUC42/bcb.html, http://www.sternwarte.uni-erlangen.de/pub/bcb or http://www.astro.uvic.ca/∼robb/bcb/comm42bcb.html The bibliographical entries for Individual Stars and Collections of Data, as well as a few General entries, are categorized according to the following coding scheme. Data from archives or databases, or previously published, are identified with an asterisk. The observation codes in the first four groups may be followed by one of the following wavelength codes. g. γ-ray. i. infrared. m. microwave. o. optical r. radio u. ultraviolet x. x-ray 1. Photometric data a. CCD b. Photoelectric c. Photographic d. Visual 2. Spectroscopic data a. Radial velocities b. Spectral classification c. Line identification d. Spectrophotometry 3. Polarimetry a. Broad-band b. Spectropolarimetry 4. Astrometry a. Positions and proper motions b. Relative positions only c. Interferometry 5. Derived results a. Times of minima b. New or improved ephemeris, period variations c. Parameters derivable from light curves d. Elements derivable from velocity curves e. Absolute dimensions, masses f. Apsidal motion and structure constants g. Physical properties of stellar atmospheres h. Chemical abundances i. Accretion disks and accretion phenomena j. Mass loss and mass exchange k. Rotational velocities 6. Catalogues, discoveries, charts a.
    [Show full text]
  • The Star Newsletter
    THE HOT STAR NEWSLETTER ? An electronic publication dedicated to A, B, O, Of, LBV and Wolf-Rayet stars and related phenomena in galaxies No. 37 February 1998 editor: Philippe Eenens http://www.astro.ugto.mx/∼eenens/hot/ [email protected] http://www.star.ucl.ac.uk/∼hsn/index.html Contents of this newsletter Abstracts of 6 accepted papers . 1 Abstracts of 2 submitted papers . .4 Abstract of 2 dissertation theses . 6 Accepted Papers The WC10 Central Stars CPD–56o8032 and He 2–113: III. Wind Electron Temperature and Abundances O. De Marco, P. J. Storey and M. J.Barlow Dept. of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK We present a direct spectroscopic measurement of the wind electron temperatures and a determination of the stellar wind abundances of the WC10 central stars of planetary nebulae CPD–56o8032 and He 2– 113, for which high resolution (0.15 A)˚ UCLES echelle spectra have been obtained using the 3.9 m AAT. The intensities of dielectronic recombination lines, originating from auto–ionising resonance states situated in the C2+ + e− continuum, are sensitive to the electron temperature through the populations of these states which are close to their LTE values. The high resolution spectra allow the intensities of fine–structure components of the dielectronic multiplets to be measured. New atomic data for the autoionization and radiative transition probabilities of the resonance states are presented and used to derive wind electron temperatures in the two stars of 21 300 K for CPD–56o8023 and 16 400 K for He 2–113.
    [Show full text]
  • The Mimes Survey of Magnetism in Massive Stars: Magnetic Analysis of the O-Type Stars
    MNRAS 000, 1–42 (2016) Preprint 26 October 2016 Compiled using MNRAS LATEX style file v3.0 The MiMeS survey of magnetism in massive stars: Magnetic analysis of the O-type stars J.H. Grunhut1,2⋆, G.A. Wade3, C. Neiner4, M.E. Oksala4,5, V. Petit6, E. Alecian4,7, D.A. Bohlender8, J.-C. Bouret9, H.F. Henrichs10, G.A.J. Hussain1, O. Kochukhov11, and the MiMeS Collaboration 1European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching bei Munchen,¨ Germany 2Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON, M5S 3H4, Canada 3Department of Physics, Royal Military College of Canada, PO Box 17000, Kingston, Ontario, K7K 7B4, Canada 4LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universit´es, UPMC Univ. Paris 06, Univ. Paris Diderot, Sorbonne Paris Cit´e, 5 place Jules Janssen, 92195 Meudon, France 5Department of Physics, California Lutheran University, 60 West Olsen Road #3700, Thousand Oaks, CA, 91360 6Department of Physics & Space Sciences, Florida Institute of Technology, Melbourne, FL 32901, USA 7UJF-Grenoble 1/CNRS-INSU, Institut de Plan´etologie et d’Astrophysique de Grenoble, UMR 5274, 38041 Grenoble, France 8Dominion Astrophysical Observatory, Herzberg Astronomy and Astrophysics Program, National Research Council of Canada, 5071 West Saanich Road, Victoria, BC V9E 2E7, Canada 9Aix Marseille Universit´e, CNRS, LAM (Laboratoire d’Astrophysique de Marseille) UMR 7326, 13388, Marseille, France 10Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands 11Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120 Uppsala, Sweden Accepted XXX.
    [Show full text]
  • The Local Cygnus Cold Cloud and Further Constraints on a Local Hot Bubble
    University of Louisville ThinkIR: The University of Louisville's Institutional Repository Electronic Theses and Dissertations 8-2015 The local Cygnus cold cloud and further constraints on a local hot bubble. Geoffrey Robert Lentner University of Louisville Follow this and additional works at: https://ir.library.louisville.edu/etd Part of the Physics Commons Recommended Citation Lentner, Geoffrey Robert, "The local ygnC us cold cloud and further constraints on a local hot bubble." (2015). Electronic Theses and Dissertations. Paper 2213. https://doi.org/10.18297/etd/2213 This Master's Thesis is brought to you for free and open access by ThinkIR: The nivU ersity of Louisville's Institutional Repository. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of ThinkIR: The nivU ersity of Louisville's Institutional Repository. This title appears here courtesy of the author, who has retained all other copyrights. For more information, please contact [email protected]. THE LOCAL CYGNUS COLD CLOUD AND FUTHER CONSTRAINTS ON A LOCAL HOT BUBBLE By Geoffrey Robert Lentner B.S., Purdue University, 2013 A Thesis Submitted to the Faculty of the College of Arts and Sciences of the University of Louisville in Partial Fulfillment of the Requirements for the Degree of Master of Science in Physics Department of Physics and Astronomy University of Louisville Louisville, Kentucky August 2015 Copyright 2015 by Geoffrey Robert Lentner All rights reserved THE LOCAL CYGNUS COLD CLOUD AND FUTHER CONSTRAINTS ON A LOCAL HOT BUBBLE By Geoffrey Robert Lentner B.S., Purdue University, 2013 A Thesis Approved On July 20, 2015 by the following Thesis Committee: Thesis Director James Lauroesch Lutz Haberzettl John Kielkopf Ryan Gill ii DEDICATION This work is dedicated to my two beautiful boys, Henry and Charlie.
    [Show full text]
  • Gamma-Ray Observations Of
    Gamma-Ray Observations of SLAC Summer Institute, August 4th - August 15, 2008 Olaf Reimer Hansen Experimental Physics Labs & Kavli Institute for Particle Astrophysics and Cosmology, Stanford University AGILE first gamma-ray detection of a GRB: GRB 080514B (Mereghetti et al., to be submitted) SuperAGILE 1-D SuperAGILE – Mars Odyssey annulus GRB 080514B has been localized jointly by SuperAGILE and IPN (GCN 7715) and shows a significant gamma ray emission (GCN 7716). Follow-up by Swift (GCN 7719 and 7750) provided the afterglow in X-rays. Many telescopes participated in the observation of the optical afterglow: Watcher (GCN 7718), GRON (GCN 7722), KPNO (GCN 7725) and NOT (GCN 7734). Gamma-ray Observations of Supernova Remnants EGRET sources and Supernova Remnants A mixed blessing: • Spatial coincidences of UNIDs and cataloged (radio-)SNRs -23.0 2.00 W28 W44 -23.2 1.75 -23.4 1.50 Dec lination Dec lination -23.6 1.25 -23.8 1.00 270.4 270.2 270.0 269.8 269.6 284.75 284.50 284.25 284.00 R.A. R.A. γ Cyg 41.5 IC443 22.8 41.0 22.6 Declination Declination 40.5 22.4 40.0 Esposito et al. 1996 306.0 305.5 305.0 304.5 304.0 94.6 94.4 94.2 R.A. R.A. • No detections in cases like SN1006, Tycho & Kepler • multifrequency support, that several synchrotron nebulae in SNR harbour magnetospherically active neutron stars (i.e. CTA1) • GeV-measured gamma-ray source positions do not correlate well with X- ray bright rim/shell features (although hampered by angular resolution) • GeV-cutoffs already significant in EGRET-spectra → serious consideration of neutron star origin at GeV SNR-associations CTA1 W28 γCyg IC443 Zhang & Cheng 98 Cheng & Zhang 98 EGRET sources and Supernova Remnants – the X-ray view on the associations Cas A : central X-ray point source (Chakrabarty et al.
    [Show full text]
  • An Evaluation of the Membership Probability of 212$\Lambda $ Boo Stars: I. a Catalogue
    Mon. Not. R. Astron. Soc. 000, 000–000 (0000) Printed 18 July 2018 (MN LATEX style file v2.2) An evaluation of the membership probability of 212 λ Boo stars: I. A Catalogue. Simon J. Murphy1,2,†, Christopher J. Corbally3, Richard O. Gray4, Kwang-Ping Cheng5, James E. Neff6, Chris Koen7, Charles A. Kuehn1,2, Ian Newsome4 and Quinlin Riggs4 1 Sydney Institute for Astronomy (SIfA), School of Physics, University of Sydney, NSW 2006, Australia 2 Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark 3 Vatican Observatory Research Group, Steward Observatory, Tucson, AZ 85721-0065, USA 4 Department of Physics and Astronomy, Appalachian State University, Boone, NC 28608, USA 5 Department of Physics, California State University, Fullerton, CA, USA 6 Department of Physics and Astronomy, College of Charleston, Charleston, SC, USA 7 Department of Statistics, University of the Western Cape, Private Bag X17, Bellville, 7535 Cape, South Africa †email: [email protected] 18 July 2018 ABSTRACT The literature on the λ Boo stars has grown to become somewhat heterogenous, as different authors have applied different criteria across the UV, optical and infrared regions to determine the membership status of λ Boo candidates. We aim to clear up the confusion by consulting the literature on 212 objects that have been consid- ered as λ Boo candidates, and subsequently evaluating the evidence in favour of their admission to the λ Boo class. We obtained new spectra of ∼90 of these candidates and classified them on the MK system to aid in the membership evaluations.
    [Show full text]
  • August 2019 BRAS Newsletter
    A Monthly Meeting August 12th at 7PM at HRPO (Monthly meetings are on 2nd Mondays, Highland Road Park Observatory). Program: John Nagle will share his experiences at the Texas Star Party last May, includes video. What's In This Issue? President’s Message Secretary's Summary Outreach Report Astrophotography Group Asteroid and Comet News Light Pollution Committee Report Globe at Night Member’s Corner – John Nagle at the Texas Star Party Messages from the HRPO Science Academy Friday Night Lecture Series Solar Viewing Perseid Meteor Shower Celestial Fantasia Plus Night Observing Notes: Cygnus – The Swan & Mythology Like this newsletter? See PAST ISSUES online back to 2009 Visit us on Facebook – Baton Rouge Astronomical Society Newsletter of the Baton Rouge Astronomical Society Page 2 August 2019 © 2019 President’s Message July 20, 2019, marked the 50th anniversary of the Apollo 11 Moon Landing. I was able to attend the Astronomical League’s 50th anniversary celebration of the moon landing, held in Titusville, Florida from July 25th through July 29th, 2019, and their cruise to the Bahamas on the Mariner Of The Seas. It was great fun. We went to the Kennedy Space Center to meet Astronaut Al Worden. We also saw the July 25 SpaceX launch from the parking lot of a Cracker Barrel restaurant near the hotel. Food and talk were great. AL’s Apollo 11 cruise to the Bahamas on Royal Caribbean’s “Mariner Of The Seas” ALCON 2018 and 2019 was so much fun I believe we should host one. I am setting up the "ALCON 2022 Bid Preparation and Planning Committee" to look into it.
    [Show full text]
  • Arxiv:1104.4810V2
    Version 3 - Accepted by AJ An Interferometric and Spectroscopic Analysis of the Multiple Star System HD 193322 Theo A. ten Brummelaar1, David P. O’Brien2, Brian D. Mason3, Christopher D. Farrington1, Alexander W. Fullerton4,5, Douglas R. Gies2, Erika D. Grundstrom6,7, William I. Hartkopf3, Rachel A. Matson2, Harold A. McAlister2, M. Virginia McSwain7,8, Lewis C. Roberts, Jr.9, Gail H. Schaefer1, Sergio Sim´on-D´ıaz10, Judit Sturmann1, Laszlo Sturmann1, Nils H. Turner1, and Stephen J. Williams2,11 ABSTRACT 1Center for High Angular Resolution Astronomy, Georgia State University, Mt. Wilson, CA 91023; [email protected], [email protected], [email protected], [email protected] 2Center for High Angular Resolution Astronomy, Department of Physics and Astronomy, Georgia State University, P.O. Box 4106, Atlanta, GA 30302-4106; [email protected], [email protected], rmat- [email protected], [email protected], [email protected] 3U. S. Naval Observatory, 3450 Massachusetts Avenue, NW, Washington, DC 20392-5420; [email protected], [email protected] 4Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218; [email protected] 5Based on observations obtained at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council of Canada, the Institut National des Sciences de l’Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii. 6Physics and Astronomy Department, Vanderbilt University, 6301 Stevenson Center, Nashville, TN 37235; [email protected] 7Visiting Astronomer, Kitt Peak National Observatory, National Optical Astronomy Observatory, oper- arXiv:1104.4810v2 [astro-ph.SR] 27 Apr 2011 ated by the Association of Universities for Research in Astronomy, Inc., under contract with the National Science Foundation.
    [Show full text]
  • X-Ray Irradiation of the Winds in Binaries with Massive Components⋆
    A&A 579, A111 (2015) Astronomy DOI: 10.1051/0004-6361/201525637 & c ESO 2015 Astrophysics X-ray irradiation of the winds in binaries with massive components J. Krtickaˇ 1,J.Kubát2, and I. Krtickovᡠ1 1 Ústav teoretické fyziky a astrofyziky, Masarykova univerzita, Kotlárskᡠ2, 611 37 Brno, Czech Republic e-mail: [email protected] 2 Astronomický ústav, Akademie vedˇ Ceskéˇ republiky, Fricovaˇ 298, 251 65 Ondrejov,ˇ Czech Republic Received 10 January 2015 / Accepted 20 April 2015 ABSTRACT Context. Binaries with hot massive components are strong X-ray sources. Besides the intrinsic X-ray emission of individual binary members originating in their winds, X-ray emission stems from the accretion on the compact companion or from wind collision. Since hot star winds are driven by the light absorption in the lines of heavier elements, wind acceleration is sensitive to the ionization state. Therefore, the over-ionization induced by external X-ray source strongly influences the winds of individual components. Aims. We studied the effect of external X-ray irradiation on hot star winds. Methods. We used our kinetic equilibrium (NLTE) wind models to estimate the influence of external X-ray ionization for different X-ray luminosities and source distances. The models are calculated for parameters typical of O stars. Results. The influence of X-rays is given by the X-ray luminosity, by the optical depth between a given point and the X-ray source, and by a distance to the X-ray source. Therefore, the results can be interpreted in the diagrams of X-ray luminosity vs.
    [Show full text]
  • Curriculum Vitae
    Curriculum Vitae Dr. Theo ten Brummelaar August 8, 2018 Home Work XXXXXXXXXXXXXXXXX The CHARA Array of Altadena, CA 91001 Georgia State University U.S.A. PO Box 48 Mount Wilson, CA 91023, U.S.A. Ph: (XXX)-XXX-XXXX Ph: (+1 626)-796-8607 Cell: (XXX)-XXX-XXXX FAX: (+1 626)-796-6717 email: [email protected] email: [email protected] WWW: http://www.astro.gsu.edu/∼theo Date of Birth: Second of May, 1962. Citizenship: United States & Australia. Employment History: • Center for High Angular Resolution Astronomy (CHARA - Georgia State University): { September 2015 - Present: Director of the CHARA Array { March 2001 - July 2015: Associate Director of CHARA { May 1996 - February 2001 : Research Scientist II. { April 1993 - April 1996 : Postdoctoral Research Fellow. • University of Sydney: 2008-present Honorary Appointment at the School of Physics • Partner in CHIP software company: January 1989 - January 1993. Clients included: { University of New South Wales: Civil Engineering Department, Road illumina- tion simulation software. { University of Sydney: Music Department, MIDI Music/Studio control software. { Commonwealth Scientific and Industrial Research Organisation: Non-destructive test group, FTI a large gear testing instrument. • Lamplight Theatre: 1990. Actor. • Continuing Education Programme (Sydney University) : March 1989 - 1991. Lecturer in a basic Astronomy course for adults entitled `Introduction to Astronomy'. 1 • Special Broadcasting Service : April 1980 - December 1992. Part-time Radio Broadcast Operator, Producer and Sound Engineer. • Commonwealth Scientific and Industrial Research Organisation (CSIRO), Division of Applied Physics : Experimental Scientist December 1985 - November 1988. Working on the development of a new 3-D ultrasonic scanning and imaging system for the metal and airline industries.
    [Show full text]
  • University Microfilms, Inc., Ann Arbor, Michigan a STUDY of MULTIPLE STAR SYSTEMS INVOLVING
    This dissertation has been microfilmed exactly as received 68-3028 MEISEL, David Dering, 1940- A STUDY OF MULTIPLE STAR SYSTEMS INVOLVING COMPONENTS OF SPECIAL A ST RO PHY SICA L INTEREST. The Ohio State University, Ph.D., 1967 Astronomy University Microfilms, Inc., Ann Arbor, Michigan A STUDY OF MULTIPLE STAR SYSTEMS INVOLVING. COMPONENTS OF SPECIAL ASTROPHYSICAL INTEREST DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By David. Dering Meisel, B.S., M.S. The Ohio State University 1967 Approved by Adviser Department of Astronomy ACKNOWLEDGMENTS I would like to thank Dr. Arne Slettebak, Dr. George Collins, and Dr. Phillip Keenan of the Perkins Observatory Staff for their suggestions, comments and patience during all phases of this work. Also I would like to thank Dr. Walter Mitchell for the loan of the Gerber GOAT in order to complete the microphotometer reduction. Also I would thank Dr. Carlos and Mercedes Jaschek for reading the manuscript, particularly the notes to Table 6, and for their valuable comments. The help of a number of other people and institutions is also grate­ fully acknowledged; in particular, Father F. J. Heyden at Georgetown College Observatory for time on their microphotometer, Ted Fay and Dr. Holis Johnson for the radial velocity reduction program and three runs on the Indiana University CDC computer, and the staff of the University of Virginia Computer Science Center for generous support. I would, like to thank my colleagues at the Leander McCormick Obser­ vatory for suggestions and their aid of telescope time and equipment with­ out which the photometry could not have been completed.
    [Show full text]