The VLT-FLAMES Tarantula Survey XVII. Physical and Wind Properties of Massive Stars at the Top of the Main Sequence
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Limits from the Hubble Space Telescope on a Point Source in SN 1987A
Limits from the Hubble Space Telescope on a Point Source in SN 1987A The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Graves, Genevieve J. M., Peter M. Challis, Roger A. Chevalier, Arlin Crotts, Alexei V. Filippenko, Claes Fransson, Peter Garnavich, et al. 2005. “Limits from the Hubble Space Telescopeon a Point Source in SN 1987A.” The Astrophysical Journal 629 (2): 944–59. https:// doi.org/10.1086/431422. Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:41399924 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA The Astrophysical Journal, 629:944–959, 2005 August 20 # 2005. The American Astronomical Society. All rights reserved. Printed in U.S.A. LIMITS FROM THE HUBBLE SPACE TELESCOPE ON A POINT SOURCE IN SN 1987A Genevieve J. M. Graves,1, 2 Peter M. Challis,2 Roger A. Chevalier,3 Arlin Crotts,4 Alexei V. Filippenko,5 Claes Fransson,6 Peter Garnavich,7 Robert P. Kirshner,2 Weidong Li,5 Peter Lundqvist,6 Richard McCray,8 Nino Panagia,9 Mark M. Phillips,10 Chun J. S. Pun,11,12 Brian P. Schmidt,13 George Sonneborn,11 Nicholas B. Suntzeff,14 Lifan Wang,15 and J. Craig Wheeler16 Received 2005 January 27; accepted 2005 April 26 ABSTRACT We observed supernova 1987A (SN 1987A) with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST ) in 1999 September and again with the Advanced Camera for Surveys (ACS) on the HST in 2003 November. -
FY13 High-Level Deliverables
National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2013 (1 October 2012 – 30 September 2013) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 13 December 2013 Revised 18 September 2014 Contents NOAO MISSION PROFILE .................................................................................................... 1 1 EXECUTIVE SUMMARY ................................................................................................ 2 2 NOAO ACCOMPLISHMENTS ....................................................................................... 4 2.1 Achievements ..................................................................................................... 4 2.2 Status of Vision and Goals ................................................................................. 5 2.2.1 Status of FY13 High-Level Deliverables ............................................ 5 2.2.2 FY13 Planned vs. Actual Spending and Revenues .............................. 8 2.3 Challenges and Their Impacts ............................................................................ 9 3 SCIENTIFIC ACTIVITIES AND FINDINGS .............................................................. 11 3.1 Cerro Tololo Inter-American Observatory ....................................................... 11 3.2 Kitt Peak National Observatory ....................................................................... 14 3.3 Gemini Observatory ........................................................................................ -
The VLT-FLAMES Tarantula Survey
Astronomy & Astrophysics manuscript no. msOrevfinalcorr c ESO 2019 May 8, 2019 The VLT-FLAMES Tarantula Survey XIV. The O-Type Stellar Content of 30 Doradus N. R. Walborn1, H. Sana1,2, S. Sim´on-D´ıaz3,4, J. Ma´ız Apell´aniz5, W. D. Taylor6,7, C. J. Evans7, N. Markova8, D. J. Lennon9, and A. de Koter2,10 1 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA 2 Astronomical Institute Anton Pannekoek, University of Amsterdam, Kruislaan 403, 1098 SJ, Amsterdam, The Netherlands 3 Instituto de Astrof´ısica de Canarias, E-38200 La Laguna, Tenerife, Spain 4 Departamento de Astrof´ısica, Universidad de La Laguna, E-38205 La Laguna, Tenerife, Spain 5 Instituto de Astrof´ısica de Andaluc´ıa-CSIC, Glorieta de la Astronom´ıa s/n, E-18008 Granada, Spain 6 Scottish Universities Physics Alliance, Institute for Astronomy, University of Edinburgh, Royal Observatory Edinburgh, Blackford Hill, Edinburgh, EH9 3HJ, UK 7 UK Astronomy Technology Centre, Royal Observatory Edinburgh, Blackford Hill, Edinburgh EH9 3HJ, UK 8 Institute of Astronomy, National Astronomical Observatory, Bulgarian Academy of Sciences, PO Box 136, 4700 Smoljan, Bulgaria 9 European Space Agency, European Space Astronomy Centre, Camino Bajo del Castillo s/n, Urbanizaci´on Villafranca del Castillo, E-28691 Villanueva de la Ca˜nada, Madrid, Spain 10 Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium ABSTRACT Detailed spectral classifications are presented for 352 O–B0 stars in the VLT-FLAMES Tarantula Survey ESO Large Programme, of which 213 O-type are judged of sufficiently high quality for further morphological analysis. -
The Tarantula Nebula As a Template for Extragalactic Star Forming Regions from VLT/MUSE and HST/STIS
This is a repository copy of The Tarantula Nebula as a template for extragalactic star forming regions from VLT/MUSE and HST/STIS. White Rose Research Online URL for this paper: http://eprints.whiterose.ac.uk/112327/ Version: Accepted Version Proceedings Paper: Crowther, P.A., Caballero-Nieves, S.M., Castro, N. et al. (1 more author) (2016) The Tarantula Nebula as a template for extragalactic star forming regions from VLT/MUSE and HST/STIS. In: Proceedings of the International Astronomical Union. IAUS 329: The Lives and Death-Throes of Massive Stars, 28 Nov - 02 Dec 2016, Auckland, New Zealand. Cambridge University Press , pp. 292-296. https://doi.org/10.1017/S1743921317002484 Reuse Unless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version - refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher’s website. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request. [email protected] https://eprints.whiterose.ac.uk/ The lives and death-throes of massive stars Proceedings IAU Symposium No. -
The R136 Star Cluster Dissected with Hubble Space Telescope/STIS. II
This is a repository copy of The R136 star cluster dissected with Hubble Space Telescope/STIS. II. Physical properties of the most massive stars in R136. White Rose Research Online URL for this paper: http://eprints.whiterose.ac.uk/166782/ Version: Accepted Version Article: Bestenlehner, J.M. orcid.org/0000-0002-0859-5139, Crowther, P.A., Caballero-Nieves, S.M. et al. (11 more authors) (2020) The R136 star cluster dissected with Hubble Space Telescope/STIS. II. Physical properties of the most massive stars in R136. Monthly Notices of the Royal Astronomical Society. ISSN 0035-8711 https://doi.org/10.1093/mnras/staa2801 This is a pre-copyedited, author-produced version of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. The version of record [Joachim M Bestenlehner, Paul A Crowther, Saida M Caballero-Nieves, Fabian R N Schneider, Sergio Simón-Díaz, Sarah A Brands, Alex de Koter, Götz Gräfener, Artemio Herrero, Norbert Langer, Daniel J Lennon, Jesus Maíz Apellániz, Joachim Puls, Jorick S Vink, The R136 star cluster dissected with Hubble Space Telescope/STIS. II. Physical properties of the most massive stars in R136, Monthly Notices of the Royal Astronomical Society, , staa2801] is available online at: https://doi.org/10.1093/mnras/staa2801 Reuse Items deposited in White Rose Research Online are protected by copyright, with all rights reserved unless indicated otherwise. They may be downloaded and/or printed for private study, or other acts as permitted by national copyright laws. The publisher or other rights holders may allow further reproduction and re-use of the full text version. -
2Df-Aaomega Spectroscopy of Massive Stars in the Magellanic Clouds the North-Eastern Region of the Large Magellanic Cloud?,??
A&A 584, A5 (2015) Astronomy DOI: 10.1051/0004-6361/201525882 & c ESO 2015 Astrophysics 2dF-AAOmega spectroscopy of massive stars in the Magellanic Clouds The north-eastern region of the Large Magellanic Cloud?;?? C. J. Evans1, J. Th. van Loon2, R. Hainich3, and M. Bailey4;2 1 UK Astronomy Technology Centre, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ, UK e-mail: [email protected] 2 Astrophysics Group, School of Physical and Geographical Sciences, Lennard-Jones Laboratories, Keele University, ST5 5BG, UK 3 Institute for Physics and Astronomy, University of Potsdam, 14476 Potsdam, Germany 4 Astrophysics Research Institute, Liverpool John Moores University, Liverpool Science Park ic2, 146 Brownlow Hill, Liverpool L3 5RF, UK Received 13 February 2015 / Accepted 5 August 2015 ABSTRACT We present spectral classifications from optical spectroscopy of 263 massive stars in the north-eastern region of the Large Magellanic Cloud. The observed two-degree field includes the massive 30 Doradus star-forming region, the environs of SN1987A, and a number of star-forming complexes to the south of 30 Dor. These are the first classifications for the majority (203) of the stars and include eleven double-lined spectroscopic binaries. The sample also includes the first examples of early OC-type spectra (AAΩ 30 Dor 248 and 280), distinguished by the weakness of their nitrogen spectra and by C IV λ4658 emission. We propose that these stars have relatively unprocessed CNO abundances compared to morphologically normal O-type stars, indicative of an earlier evolutionary phase. From analysis of observations obtained on two consecutive nights, we present radial-velocity estimates for 233 stars, finding one apparent single-lined binary and nine (>3σ) outliers compared to the systemic velocity; the latter objects could be runaway stars or large-amplitude binary systems and further spectroscopy is required to investigate their nature. -
Massive Runaway Stars in the Large Magellanic Cloud Sive (O2-Type) Stars Is Located at 100 200 Pc in Projection Table 1
Astronomy & Astrophysics manuscript no. LMC2 c ESO 2018 October 14, 2018 Massive runaway stars in the Large Magellanic Cloud V.V. Gvaramadze1,2,3, P. Kroupa1, and J. Pflamm-Altenburg1 1 Argelander-Institut f¨ur Astronomie, Universit¨at Bonn, Auf dem H¨ugel 73, 53121 Bonn, Germany e-mail: [email protected] (PK); [email protected] (JP-A) 2 Sternberg Astronomical Institute, Moscow State University, Universitetskij Pr. 13, Moscow 119992, Russia e-mail: [email protected] (VVG) 3 Isaac Newton Institute of Chile, Moscow Branch, Universitetskij Pr. 13, Moscow 119992, Russia Received 27 April 2010/ Accepted 26 May 2010 ABSTRACT The origin of massive field stars in the Large Magellanic Cloud (LMC) has long been an enigma. The recent measurements of large 1 offsets ( 100 km s− ) between the heliocentric radial velocities of some very massive (O2-type) field stars and the systemic LMC velocity∼ provides a possible explanation of this enigma and suggests that the field stars are runaway stars ejected from their birthplaces at the very beginning of their parent cluster’s dynamical evolution. A straightforward way to prove this explanation is to measure the proper motions of the field stars and to show that they are moving away from one of the nearby star clusters or OB associations. This approach is, however, complicated by the long distance to the LMC, which makes accurate proper motion measurements difficult. We used an alternative approach for solving the problem (first applied for Galactic field stars), based on the search for bow shocks produced by runaway stars. -
Dealing with $\Delta $-Scuti Variables: Transit Light Curve Analysis of Planets Orbiting Rapidly-Rotating, Seismically Active A/F Stars
Draft version July 31, 2019 Typeset using LATEX twocolumn style in AASTeX62 Dealing With δ-Scuti Variables: Transit Light Curve Analysis of Planets Orbiting Rapidly-Rotating, Seismically Active A/F Stars John P. Ahlers,1, 2 Jason W. Barnes,1 and Samuel A. Myers1 1Physics Department, University of Idaho, Moscow, ID 83844 2Exoplanets and Stellar Astrophysics Laboratory, Code 667, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA Abstract We measure the bulk system parameters of the seismically active, rapidly-rotating δ-Scuti KOI- 976 and constrain the orbit geometry of its transiting binary companion using a combined approach of asteroseismology and gravity-darkening light curve analysis. KOI-976 is a 1:62 ± 0:2 M star with a measured v sin(i) of 120 ± 2 km/s and seismically-induced variable signal that varies by ∼ 0.6% of the star's total photometric brightness. We take advantage of the star's oblate shape and seismic activity to perform three measurements of its obliquity angle relative to the plane of the sky. We first apply rotational splitting theory to the star's variable signal observed in short-cadence Kepler photometry to constrain KOI-976's obliquity angle, and then subtract off variability from that dataset using the linear algorithm for significance reduction software LASR. We perform gravity- darkened fits to Kepler variability-subtracted short-cadence photometry and to Kepler's phase-folded long-cadence photometry to obtain two more measurements of the star's obliquity. We find that the binary system transits in a grazing configuration with measured obliquity values of 36◦ ± 17◦, 46◦ ± 16◦, and 43◦ ± 20◦ respectively for the three measurements. -
The R136 Star Cluster Dissected with Hubble Space Telescope/STIS
MNRAS 000, 1–39 (2015) Preprint 29 January 2016 Compiled using MNRAS LATEXstylefilev3.0 The R136 star cluster dissected with Hubble Space Telescope/STIS. I. Far-ultraviolet spectroscopic census and the origin of He ii λ1640 in young star clusters Paul A. Crowther1⋆, S.M. Caballero-Nieves1, K.A. Bostroem2,3,J.Ma´ız Apell´aniz4, F.R.N. Schneider5,6,N.R.Walborn2,C.R.Angus1,7,I.Brott8,A.Bonanos9, A. de Koter10,11,S.E.deMink10,C.J.Evans12,G.Gr¨afener13,A.Herrero14,15, I.D. Howarth16, N. Langer6,D.J.Lennon17,J.Puls18,H.Sana2,11,J.S.Vink13 1Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, UK 2Space Telescope Science Institute, 3700 San Martin Drive, Baltimore MD 21218, USA 3Department of Physics, University of California, Davis, 1 Shields Ave, Davis CA 95616, USA 4Centro de Astrobiologi´a, CSIC/INTA, Campus ESAC, Apartado Postal 78, E-28 691 Villanueva de la Ca˜nada, Madrid, Spain 5 Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH, UK 6 Argelanger-Institut fur¨ Astronomie der Universit¨at Bonn, Auf dem Hugel¨ 71, D-53121 Bonn, Germany 7 Department of Physics, University of Warwick, Gibbet Hill Rd, Coventry CV4 7AL, UK 8 Institute for Astrophysics, Tuerkenschanzstr. 17, AT-1180 Vienna, Austria 9 Institute of Astronomy & Astrophysics, National Observatory of Athens, I. Metaxa & Vas. Pavlou St, P. Penteli 15236, Greece 10 Astronomical Institute Anton Pannekoek, University of Amsterdam, Kruislaan 403, 1098 SJ, Amsterdam, Netherlands 11 Institute of Astronomy, KU Leuven, Celestijnenlaan -
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 -
19810018458.Pdf
N O T I C E THIS DOCUMENT HAS BEEN REPRODUCED FROM MICROFICHE. ALTHOUGH IT IS RECOGNIZED THAT CERTAIN PORTIONS ARE ILLEGIBLE, IT IS BEING RELEASED IN THE INTEREST OF MAKING AVAILABLE AS MUCH INFORMATION AS POSSIBLE 5 DISTRIBU."ION OF HOT STARS AND HYDROGEN IN THE LARGE MAGELLANIC CLOUD THORNTON PACE NASA Johnson Space tenter Houston, Texas 77058 ..•' V I ^^^sMMM V 4 .^j J GEORGE R. CARRUTHERS E. 0. Hul,burt Center for Space Research Navin. Research Laboratory JUL1081 Washington, D.C. 20375 RECEIVED NR$A 3TI FACILITY 4 ACCESS DEPT. ABSTRACT Imagery of the Large Magellanic Cloud, in the wavelength ranges 1050- 1600 A and 1250-1600 A, was obtained by the S201 Far Ultraviolet Camera during the Apollo 16 mission in April 1972. These images have been reduced to absolute far-UV intensity distributions over the area of the LMC, wit-h 3-5 arc min angular resolution. Comparison of our far-UV measurements in the LMC with Ha and 21-cm surveys reveals that interstellar hydrogen in the LMC is often concentrated in 100-pc clouds within the 500-pc clouds detected by McGee and Milton. Furthermore, at least 2.5 associations of 0- B stars in the LMC are outside the interstellar hydrogen clouds; four of them appear to be on the far side. Far-UV and . mid-*UV spectra were obtained of stars in 12 of these associations, using the International Ultraviolet Explorer. Equivalent widths of La and six other lines, and relative intensities of the continuum at seven wavelenths from 1300 A to 2900 A, have been measured and are discussed. -
1995Apjs ... 99. .565S the Astrophysical Journal
The Astrophysical Journal Supplement Series, 99:565-607,1995 August .565S © 1995. The American Astronomical Society. All rights reserved. Printed in U.S.A. 99. ... CHEMISTRY IN DENSE PHOTON-DOMINATED REGIONS 1995ApJS A. Sternberg School of Physics and Astronomy, Tel Aviv University, Ramat Aviv 69978, Israel AND A. Dalgarno Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 Received 1994 March 17; accepted 1994 August 10 ABSTRACT We present a detailed chemical model of a photon-dominated region produced in a dense molecular cloud exposed to an intense far-ultraviolet radiation field. We use it to illustrate the gas-phase processes that lead to the production of atomic and molecular species in the several distinct zones that occur in the cloud. We identify molecular diagnostics of photon-dominated chemistry in dense molecular clouds. Subject headings: galaxies: ISM — ISM: molecules — molecular processes 1. INTRODUCTION the Infrared Space Observatory {ISO) (Encrenaz & Kessler Photon-dominated regions (PDRs) form in neutral hy- 1992). drogen clouds which are exposed to far-ultraviolet (FUV) ra- Theoretical models of photon-dominated regions have been diation fields (6-13.6 eV) from external sources (de Jong, constructed and developed by several research groups (e.g., Dalgarno, & Boland 1980; Tielens & Hollenbach 1985; Stern- Tielens & Hollenbach 1985; van Dishoeck & Black 1988; berg & Dalgarno 1989 ). PDRs are ubiquitous in the interstellar Sternberg & Dalgarno 1989; Le Bourlot et al. 1993; Köster et medium and are present at the edges of H n regions (Stacey et al. 1994) and have been used successfully to interpret a wide al. 1993; van der Werf et al.