ASTRONOMY and ASTROPHYSICS Understanding A-Type Supergiants II
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Interstellarum 85 • Dezember/Januar 2013 1 Inhalt
Editorial fokussiert Liebe Leserinnen und Leser, wissen Sie schon, was Sie am 21. Dezember tun werden? Wahrschein- lich werden Sie auf der Jagd nach letzten Geschenken durch die Geschäfte ziehen oder einen Glühwein auf dem Weihnachtsmarkt trinken. Geht es nach vielen Paranoikern im Internet, wird dieser Tag aber weniger beschau- lich enden – nichts weniger als der Weltuntergang ist angekündigt. Nun . t könnte uns diese unsinnige Prophezeiung so wenig interessieren wie viele g andere zuvor, doch diesmal wird die Astronomie als Schreckgespenst miss- braucht: Ein mythischer »Planet X« soll sich uns nähern, die anderen Pla- neten die Erde aus ihrer Bahn reißen, die Sonne sich mit dem Zentrum der Milchstraße »synchronisieren«, und zu allem Überfl uss »endet« auch noch ist untersa g der Kalender der Maya. Was sich hinter dieser wüsten Ankündigung ver- Ronald Stoyan, Chefredakteur birgt, haben Oliver Debus und Oliver Dreißigacker recherchiert (Seite 12). reitun Dass viele Menschen diese Ankündigungen tatsächlich glauben, berichtet b Florian Freistetter in einem Interview auf interstellarum.de. Jupiter steht nicht nur bestens platziert am Abendhimmel, sondern auch im Zentrum dieses Heftes. Neben Details zur aktuellen Oppositions- stellung (Seite 18) und Neuigkeiten von seiner veränderlichen Wolkenober- fl äche (Seite 23), bringt dieses Heft eine ausführliche Anleitung zur Beob- achtung des Riesenplaneten (Seite 34). Außerdem erklärt Peter M. Oden in seinem Beitrag, wie man aus Webcam-Aufnahmen Rotations-Animationen der Planeten erstellt (Seite 52). Nutzen Sie den idealen Stand von Jupiter für eigene Versuche! Sind Sie Astrofotograf – oder gerade dabei, einer zu werden? Dann sollten Sie unbedingt an unserem neuen Fotowettbewerb teilnehmen, zu dem wir mit der Firma Astrosysteme Austria (ASA) zusammen einladen: In den Kategorien Einsteiger und Experten sind Preise im Gesamtwert von über 15000 Euro ausgelobt – so viel gab es noch bei keinem astro- nur zu privaten Zwecken. -
Cam OB1 Region Is Investigated
NOTE TO USERS The original manuscript received by UMI contains pages with indistinct print. Pages were microfilmed as received. This reproduction is the best copy available UMI National Library Bibliothèque nationale du Canada Acquisitions and Acquisitions et Bibliographie Services services bibliographiques 395 Wellington Street 395. nie Weilington OttawaON K1AW OttawaON K1AW canada canada The author has granted a non- L'auteur a accordé une licence non exclusive licence allowing the exclusive permettant à la National Library of Canada to Bibliothèque nationale du Canada de reproduce, loan, distribute or sell reproduire, prêter, distribuer ou copies of this thesis in microfom, vendre des copies de cette thèse sous paper or electronic formats. la fome de microfiche/nlm, de reproduction sur papier ou sur format électronique. The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantial extracts 6-om it Ni la thèse ni des extraits substantiels may be printed or othenivise de celle-ci ne doivent être imprimés reproduced without the author's ou autrement reproduits sans son permission. autorisation. Supervisors: Drs. .A. C. Gower and C. R. Purton Star formation in the Cam OB1 region is investigated. Star formation. in general. is considered in terms of three elements: a) the structural relationship between the parent molecular clouds and newly formed stars. b) the temporal evolution of the parent molecular clouds, and c) the probability of the occurrence of star formation. Star formation in Cam OBI. over the range in 1 and b considered in this work. -
The Pre-Main-Sequence Star IP Persei
A&A 377, 854–867 (2001) Astronomy DOI: 10.1051/0004-6361:20010958 & c ESO 2001 Astrophysics The pre-main-sequence star IP Persei A. S. Miroshnichenko1,2,K.S.Bjorkman1,E.L.Chentsov3,4,V.G.Klochkova3,4,R.O.Gray5, P. Garc´ıa-Lario6, and J. V. Perea Calder´on7 1 Ritter Observatory, Dept. of Physics & Astronomy, University of Toledo, Toledo, OH 43606-3390, USA 2 Central Astronomical Observatory of the Russian Academy of Sciences at Pulkovo, 196140, Saint-Petersburg, Russia 3 Special Astrophysical Observatory of the Russian Academy of Sciences, Karachai-Cirkassian Republic, Nizhnij Arkhyz, 369167, Russia 4 Issac Newton Institute of Chile, SAO Branch, Russia 5 Dept. of Physics and Astronomy, Appalachian State University, Boone, NC 28608, USA 6 ISO Data Centre, Astrophysics Division, Space Science Department of ESA, Villafranca del Castillo, Apartado de Correos 50727, 28080 Madrid, Spain 7 INSA SA, Villafranca del Castillo, Apartado de Correos 50727, 28080 Madrid, Spain Received 19 March 2001 / Accepted 21 June 2001 Abstract. We present the results of high- and low-resolution spectroscopic and broadband multicolour photometric observations of the emission-line A-type star IP Per. Significant variations of the Balmer line profiles and near-IR brightness are detected. Comparison with the spectra of other stars and theoretical models allowed us to derive its fundamental parameters as follows: Teff ' 8000 K, log g ' 4.4, log Lbol/L ' 1.0. They correspond to the MK type A7 v. We also found that the metallicity of the object’s atmosphere is nearly 40 per cent that of the Sun. -
The Atmospheric Parameters and Spectral Interpolator for the MILES Stars
A&A 531, A165 (2011) Astronomy DOI: 10.1051/0004-6361/201116769 & c ESO 2011 Astrophysics The atmospheric parameters and spectral interpolator for the MILES stars Ph. Prugniel1, I. Vauglin1,andM.Koleva2,1 1 Université de Lyon, Université Lyon 1, 69622 Villeurbanne, France; CRAL, Observatoire de Lyon, CNRS UMR 5574, 69561 Saint-Genis Laval, France e-mail: [philippe.prugniel;isabelle.vauglin]@univ-lyon1.fr 2 Instituto de Astrofísica de Canarias, La Laguna, 38200 Tenerife, Spain; Departamento de Astrofísica, Universidad de La Laguna, 38205 La Laguna, Tenerife, Spain e-mail: [email protected] Received 22 February 2011 / Accepted 16 April 2011 ABSTRACT Context. Empirical libraries of stellar spectra are used to classify stars and synthetize stellar populations. MILES is a medium spectral- resolution library in the optical domain covering a wide range of temperatures, surface gravities and metallicities. Aims. We redetermine the atmospheric parameters of these stars in order to improve the homogeneity and accuracy. We build an interpolating function that returns a spectrum as a function of the three atmospheric parameters, and finally we characterize the precision of the wavelength calibration and stability of the spectral resolution. Methods. We used the ULySS program with the ELODIE library as a reference and compared the results with those in the literature. Results. We obtain precisions of 60 K, 0.13, and 0.05 dex, respectively, for Teff ,logg,and[Fe/H] for the FGK stars. For the M stars, the mean errors are 38 K, 0.26, and 0.12 dex and 3.5%, 0.17, and 0.13 dex for the OBA. -
Astrophysics
Publications of the Astronomical Institute rais-mf—ii«o of the Czechoslovak Academy of Sciences Publication No. 70 EUROPEAN REGIONAL ASTRONOMY MEETING OF THE IA U Praha, Czechoslovakia August 24-29, 1987 ASTROPHYSICS Edited by PETR HARMANEC Proceedings, Vol. 1987 Publications of the Astronomical Institute of the Czechoslovak Academy of Sciences Publication No. 70 EUROPEAN REGIONAL ASTRONOMY MEETING OF THE I A U 10 Praha, Czechoslovakia August 24-29, 1987 ASTROPHYSICS Edited by PETR HARMANEC Proceedings, Vol. 5 1 987 CHIEF EDITOR OF THE PROCEEDINGS: LUBOS PEREK Astronomical Institute of the Czechoslovak Academy of Sciences 251 65 Ondrejov, Czechoslovakia TABLE OF CONTENTS Preface HI Invited discourse 3.-C. Pecker: Fran Tycho Brahe to Prague 1987: The Ever Changing Universe 3 lorlishdp on rapid variability of single, binary and Multiple stars A. Baglln: Time Scales and Physical Processes Involved (Review Paper) 13 Part 1 : Early-type stars P. Koubsfty: Evidence of Rapid Variability in Early-Type Stars (Review Paper) 25 NSV. Filtertdn, D.B. Gies, C.T. Bolton: The Incidence cf Absorption Line Profile Variability Among 33 the 0 Stars (Contributed Paper) R.K. Prinja, I.D. Howarth: Variability In the Stellar Wind of 68 Cygni - Not "Shells" or "Puffs", 39 but Streams (Contributed Paper) H. Hubert, B. Dagostlnoz, A.M. Hubert, M. Floquet: Short-Time Scale Variability In Some Be Stars 45 (Contributed Paper) G. talker, S. Yang, C. McDowall, G. Fahlman: Analysis of Nonradial Oscillations of Rapidly Rotating 49 Delta Scuti Stars (Contributed Paper) C. Sterken: The Variability of the Runaway Star S3 Arietis (Contributed Paper) S3 C. Blanco, A. -
The Electric Sun Hypothesis
Basics of astrophysics revisited. II. Mass- luminosity- rotation relation for F, A, B, O and WR class stars Edgars Alksnis [email protected] Small volume statistics show, that luminosity of bright stars is proportional to their angular momentums of rotation when certain relation between stellar mass and stellar rotation speed is reached. Cause should be outside of standard stellar model. Concept allows strengthen hypotheses of 1) fast rotation of Wolf-Rayet stars and 2) low mass central black hole of the Milky Way. Keywords: mass-luminosity relation, stellar rotation, Wolf-Rayet stars, stellar angular momentum, Sagittarius A* mass, Sagittarius A* luminosity. In previous work (Alksnis, 2017) we have shown, that in slow rotating stars stellar luminosity is proportional to spin angular momentum of the star. This allows us to see, that there in fact are no stars outside of “main sequence” within stellar classes G, K and M. METHOD We have analyzed possible connection between stellar luminosity and stellar angular momentum in samples of most known F, A, B, O and WR class stars (tables 1-5). Stellar equatorial rotation speed (vsini) was used as main parameter of stellar rotation when possible. Several diverse data for one star were averaged. Zero stellar rotation speed was considered as an error and corresponding star has been not included in sample. RESULTS 2 F class star Relative Relative Luminosity, Relative M*R *eq mass, M radius, L rotation, L R eq HATP-6 1.29 1.46 3.55 2.950 2.28 α UMi B 1.39 1.38 3.90 38.573 26.18 Alpha Fornacis 1.33 -
Publications of the Astronomical Society of the Pacific 106: 382-396, 1994 April
Publications of the Astronomical Society of the Pacific 106: 382-396, 1994 April An Atlas of Southern MK Standards From 5800 to 10,200 A1 Anthony C. Danks Hughes STX/Goddard Space Flight Center, Code 683.0, Greenbelt, Maryland 20771 Michel Dennefeld Institut d'Astrophysique, 98bis Boulevard Arago, F-75014 Paris, France Received 1992 December 30; accepted 1994 February 2 ABSTRACT. An atlas of stellar spectra covering the wavelength range from 5800 to 10,200 A is presented of 126 southern MK standard stars, covering the luminosity classes I, III, and V. Some peculiar stars are included for comparison purposes. The spectra were obtained at a resolution of 4.3 A per pixel using a Cassegrain-mounted Boiler and Chivens spectrograph equipped with a Reticon detector. The quality and utility of the data are discussed and examples of the spectra are presented. The atlas is available in digital format through the NSSDC. 1. INTRODUCTION tion of 15 A which is lower than that used in this atlas, but overlaps nicely in wavelength. Mantegazza (1992) has be- Spectral synthesis of galaxies is one of the major driving forces for producing new stellar libraries covering as large gun the work of extending calibration to the Magellanic a spectral interval as possible. The "photographic" wave- clouds by observing 34 LMC and 15 SMC supergiants be- length region from 3800 to 4800 A, initially used for the tween AO and G5 in the wavelength range from 5600 to MK classification scheme, has been extended to shorter 9000 A, interestingly made with the same spectrograph as wavelengths through space technology. -
1970Aj 75. . 602H the Astronomical Journal
602H . 75. THE ASTRONOMICAL JOURNAL VOLUME 75, NUMBER 5 JUNE 19 70 The Space Distribution and Kinematics of Supergiants 1970AJ Roberta M. Humphreys *f University of Michigan, Ann Arbor, Michigan (Received 15 January 1970; revised 1 April 1970) The distribution and kinematics of the supergiants of all spectral types are investigated with special emphasis on the correlation of these young stars and the interstellar gas. The stars used for this study are included as a catalogue of supergiants. Sixty percent of these supergiants occur in stellar groups. Least- squares solutions for the Galactic rotation constants yield 14 km sec-1 kpc-1 for Oort’s constant and a meaningful result for the second-order coefficient of —0.6 km sec-1 kpc-2. A detailed comparison of the stellar and gas velocities in the same regions shows good agreement, and these luminous stars occur in relatively dense gas. The velocity residuals for the stars also indicate noncircular group motions. In the Carina-Centaurus region, systematic motions of 10 km/sec were found between the two sides of the arm in agreement with Lin’s density-wave theory. The velocity residuals in the Perseus arm may also be due in part to these shearing motions. I. INTRODUCTION II. THE CATALOGUE OF SUPERGIANTS SINCE the pioneering work of Morgan et al. (1952) The observational data required for this study were on the distances of Galactic H 11 regions, many largely obtained from the literature. Use of a card file investigators have studied the space distribution of compiled by Dr. W. P. Bidelman was very helpful in various Population I objects, the optical tracers of this regard. -
Redox DAS Artist List for Period: 01.08.2017
Page: 1 Redox D.A.S. Artist List for period: 01.08.2017 - 31.08.2017 Date time: Number: Title: Artist: Publisher Lang: 01.08.2017 00:02:09 HD 04463 BOBBY BROWN FRANK ZAPPA ANG 01.08.2017 00:04:55 HD 55594 LJUBEZEN HLADNEGA DEKLETA THE STICKY LICKS SLO 01.08.2017 00:09:59 HD 46532 PARTY ALL NIGHT (SLEEP ALL DAY) [ALBUMSEAN KINGSTON VERSION] ANG 01.08.2017 00:13:47 HD 40707 FLAME TREES COLD CHISEL ANG 01.08.2017 00:18:07 HD 52793 TUDI TI A-NI-TA SLO 01.08.2017 00:21:11 HD 42017 UNANSWERED PRAYERS GARTH BROOKS ANG 01.08.2017 00:24:43 HD 34818 LIFTED LIGHTHOUSE FAMILY ANG 01.08.2017 00:28:48 HD 10759 EMANUELLE MAGNIFICO SLO 01.08.2017 00:33:33 HD 16344 DO SOMETHIN' BRITNEY SPEARS ANG 01.08.2017 00:37:01 HD 36333 PUMPKIN SOUP KATE NASH ANG 01.08.2017 00:40:00 HD 52816 V RITMU SANJ KATRINAS SLO 01.08.2017 00:44:06 HD 36201 MILLION FACES PAOLO NUTINI ANG 01.08.2017 00:47:44 HD 58724 BREATHE (FEAT NEEV) SEEB ANG 01.08.2017 00:51:30 HD 12353 PRID K MEN PETER LOVSIN & VITEZI OM'A SLO 01.08.2017 00:55:11 HD 10793 EVERY BREATH YOU TAKE FAME ACADEMY ANG 01.08.2017 00:59:03 HD 42719 UNTIL I DIE SEPTEMBER ANG 01.08.2017 01:02:43 HD 44564 BREZ OBRAZA REBEKA & TRKAJ SLO 01.08.2017 01:05:54 HD 25447 QUANDO, QUANDO, QUANDO MICHAEL BUBLE FT NELLY FURTADO ANG 01.08.2017 01:10:43 HD 54865 GIVING ME AWAY BETTY WHO ANG 01.08.2017 01:14:39 HD 21353 HELENA FOLKROLA SLO 01.08.2017 01:17:57 HD 02753 DANCE (WITH YOU) LEMAR ANG 01.08.2017 01:21:27 HD 56725 DON'T WE BELONG IN LOVE STEPHANIE WINSLOW ANG 01.08.2017 01:23:43 HD 42913 HALO DAN D SLO 01.08.2017 01:27:10 HD 52736 THE WORLD IS YOURS JUSTIN'S CASE ANG 01.08.2017 01:30:59 HD 27349 LIVE YOUR LIFE BE FREE BELINDA CARLISLE ANG 01.08.2017 01:35:11 HD 50937 TINA MANCA SPIK SLO 01.08.2017 01:38:11 HD 43429 BELLE OF THE BOULEVARD DASHBOARD CONFESSIONAL ANG 01.08.2017 01:41:38 HD 13655 OBVIOUS WESTLIFE ANG 01.08.2017 01:45:02 HD 52083 SLADOLED NE ME JUGAT SLO 01.08.2017 01:48:29 HD 53183 BROTHER LOUIE MIX '98 MODERN TALKING FEAT. -
Effects of Rotation Arund the Axis on the Stars, Galaxy and Rotation of Universe* Weitter Duckss1
Effects of Rotation Arund the Axis on the Stars, Galaxy and Rotation of Universe* Weitter Duckss1 1Independent Researcher, Zadar, Croatia *Project: https://www.svemir-ipaksevrti.com/Universe-and-rotation.html; (https://www.svemir-ipaksevrti.com/) Abstract: The article analyzes the blueshift of the objects, through realized measurements of galaxies, mergers and collisions of galaxies and clusters of galaxies and measurements of different galactic speeds, where the closer galaxies move faster than the significantly more distant ones. The clusters of galaxies are analyzed through their non-zero value rotations and gravitational connection of objects inside a cluster, supercluster or a group of galaxies. The constant growth of objects and systems is visible through the constant influx of space material to Earth and other objects inside our system, through percussive craters, scattered around the system, collisions and mergers of objects, galaxies and clusters of galaxies. Atom and its formation, joining into pairs, growth and disintegration are analyzed through atoms of the same values of structure, different aggregate states and contiguous atoms of different aggregate states. The disintegration of complex atoms is followed with the temperature increase above the boiling point of atoms and compounds. The effects of rotation around an axis are analyzed from the small objects through stars, galaxies, superclusters and to the rotation of Universe. The objects' speeds of rotation and their effects are analyzed through the formation and appearance of a system (the formation of orbits, the asteroid belt, gas disk, the appearance of galaxies), its influence on temperature, surface gravity, the force of a magnetic field, the size of a radius. -
Research Collection
Research Collection Doctoral Thesis Properties of symbiotic binaries A study of selected systems Author(s): Dumm, Thomas Publication Date: 1999 Permanent Link: https://doi.org/10.3929/ethz-a-003840353 Rights / License: In Copyright - Non-Commercial Use Permitted This page was generated automatically upon download from the ETH Zurich Research Collection. For more information please consult the Terms of use. ETH Library Diss ETH No. 13147 Properties of Symbiotic Binaries A Study of Selected Systems A dissertation submitted to the SWISS FEDERAL INSTITUTE OF TECHNOLOGY for the degree of Doctor of Natural Sciences presented by Thomas Dumm Dipl. Phys. ETH born on February 9th, 1969 citizen of Germany accepted on the recommendation of Prof. Dr. Harry Nussbaumer, examiner Dr. habil. Werner Schmutz co-examiner , Prof. Dr. Jan Olof Stenflo co-examiner , Mai 1999 Va/ V*/ E t. Va# 8beibm\e/' 'W 1 {IV Properties of Symbiotic Binaries A Study of Selected Systems Diss ETH No. 13147 Thomas Dumm Seite Leer / Blank leaf Contents Introduction 1 I Properties of Symbiotic Binaries from the Study of Se¬ lected Systems 11 1 Orbital and stellar parameters of BX Monocerotis 15 1.1 Introduction 16 1.2 Spectroscopic data 17 1.2.1 Optical and near IR spectroscopy 17 1.2.2 UVdata 17 1.3 The orbital period 20 1.3.1 The light curve of BX Mon 20 1.3.2 Eclipse effects in the UV 22 1.4 Radial velocity curves and stellar masses 22 1.4.1 Radial velocity curve of the M star 22 1.4.2 Radial velocities for the hot component 25 1.4.3 Mass function and stellar masses 26 1.5 -
Mg and Tio Spectral Features at the Near-IR: Spectrophotometric Index
Mon. Not. R. Astron. Soc. 000, 1–?? (2000) Printed 25 September 2018 (MN LaTEX style file v1.4) Mg and TiO spectral features at the near-IR: Spectrophotometric index definitions and empirical calibrations ⋆ A.J. Cenarro1, N. Cardiel2, A. Vazdekis1, and J. Gorgas2 1Instituto de Astrof´ısica de Canarias, E-38200, La Laguna, Tenerife, Spain. 2Depto. de Astrof´ısica, Fac. de Ciencias F´ısicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain. Accepted 2009 March 26. Received 2008 December 4 ABSTRACT Using the near-infrared spectral stellar library of Cenarro et al. (2001a,b), the behaviours of the Mg i line at 8807 A˚ and nearby TiO bands are analyzed in terms of the effective temperature, surface gravity, and metallicity of the library stars. New spectroscopic indices for both spectral features —namely MgI and sTiO— are defined, and their sensitivities to different signal-to-noise ratios, spectral resolutions, flux cali- brations, and sky emission line residuals are characterized. The new two indices exhibit interesting properties. In particular, MgI reveals as a good indicator of the Mg abun- dance, whereas sTiO is a powerful dwarf-to-giant discriminator for cold spectral types. Empirical fitting polynomials that reproduce the strength of the new indices as a func- tion of the stellar atmospheric parameters are computed, and a fortran routine with the fitting functions predictions is made available. A thorough study of several error sources, non-solar [Mg/Fe] ratios, and their influence on the fitting function residuals is also presented. From this analysis, a [Mg/Fe] underabundance of ∼−0.04 is derived for the Galactic open cluster M67.