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The Central Density of R136 in 30 Doradus
A&A 552, A94 (2013) Astronomy DOI: 10.1051/0004-6361/201220396 & c ESO 2013 Astrophysics The central density of R136 in 30 Doradus F. J. Selman and J. Melnick European Southern Observatory, Alonso de Cordova 3107 Vitacura Casilla 7630355, Santiago, Chile e-mail: [email protected] Received 18 September 2012 / Accepted 13 February 2013 ABSTRACT The central density, ρ0, of a stellar cluster is an important physical parameter for determining its evolutionary and dynamical state. How much mass segregation there is or whether the cluster has undergone core collapse both depend on ρ0. We reanalyze the results of a previous paper that gives the mass density profile of R136 and combine them with both a conservative upper limit for the core parameter and a more uncertain recent measurement. We thus place a lower limit on ρ0 under reasonable and defensible assumptions 4 3 about the IMF, finding ρ0 ≥ 1.5 × 10 M/pc for the conservative assumption a < 0.4 pc for the cluster core parameter. If we use the 7 3 lower, but more uncertain value a = 0.025 pc, the central density estimate becomes greater than 10 M/pc . A mechanism based on the destruction of a large number of circumstellar disks is posited to explain the hitherto unexplained increase in reddening presented in that same work. Key words. circumstellar matter – galaxies: clusters: individual: R 136 – stars: luminosity function, mass function – Magellanic Clouds – dust, extinction 1. Introduction therein). The cluster R136 has been claimed to have the char- acteristics of a PCC cluster: a cuspy density profile (Mackey Owing to its nearness and extreme nature, Radcliffe 136 (Feast & Gilmore 2003), and a large number of runaway stars (see et al. -
Curriculum Vitae of You-Hua Chu
Curriculum Vitae of You-Hua Chu Address and Telephone Number: Institute of Astronomy and Astrophysics, Academia Sinica 11F of Astronomy-Mathematics Building, AS/NTU No.1, Sec. 4, Roosevelt Rd, Taipei 10617 Taiwan, R.O.C. Tel: (886) 02 2366 5300 E-mail address: [email protected] Academic Degrees, Granting Institutions, and Dates Granted: B.S. Physics Dept., National Taiwan University 1975 Ph.D. Astronomy Dept., University of California at Berkeley 1981 Professional Employment History: 2014 Sep - present Director, Institute of Astronomy and Astrophysics, Academia Sinica 2014 Jul - present Distinguished Research Fellow, Institute of Astronomy and Astrophysics, Academia Sinica 2014 Jul - present Professor Emerita, University of Illinois at Urbana-Champaign 2005 Aug - 2011 Jul Chair of Astronomy Dept., University of Illinois at Urbana-Champaign 1997 Aug - 2014 Jun Professor, University of Illinois at Urbana-Champaign 1992 Aug - 1997 Jul Research Associate Professor, University of Illinois at Urbana-Champaign 1987 Jan - 1992 Aug Research Assistant Professor, University of Illinois at Urbana-Champaign 1985 Feb - 1986 Dec Graduate College Scholar, University of Illinois at Urbana-Champaign 1984 Sep - 1985 Jan Lindheimer Fellow, Northwestern University 1982 May - 1984 Jun Postdoctoral Research Associate, University of Wisconsin at Madison 1981 Oct - 1982 May Postdoctoral Research Associate, University of Illinois at Urbana-Champaign 1981 Jun - 1981 Aug Postdoctoral Research Associate, University of California at Berkeley Committees Served: -
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. -
R136: the Core of the Lonizing Cluster of 30 Doradus J
R136: The Core of the lonizing Cluster of 30 Doradus J. Me/nick, ESO Introduction crucial role in the whole story, I will give abrief description of this remarkable object. I first read that R136 contained a supermassive object some time ago in the Sunday edition of the Chilean daily newspaper The 30 Doradus Nebula and R136 EI Mercurio, where it was announced that ... "European astronomers discover the most massive star in the Universe!". The 30 Doradus nebula (thus named because it lies in the Since EI Mercurio is almost always wrang I did not take the Constellation of Doradus) is an outstanding complex of gas, announcement very seriously until the paper by Feitzinger and dust and stars in the Large Magellanic Cloud (LMC), the Co-workers (henceforth the Bochum graup) appeared in nearest galaxy to our own. Beautiful colour photographs of the Astronomy and Astrophysics in 1980. More or less simultane LMC and the 30 Doradus region can be found in the December ously with the publication of these optical observations, a graup 1982 issue of The Messenger. The diameter of 30 Dor is of observers from the University of Wisconsin, headed by J. several hundred parsecs and, although emission nebulae as Cassinelli (henceforth the Wisconsin group) reached the same large or larger than 30 Dor exist in other galaxies, none is found Conclusion on the basis of ultraviolet observations obtained in our own. The visual light emitted by the nebula is produced with the International Ultraviolet Explorer (IUE). almost entirely by hydrogen recombination lines and in orderte . After these papers where published, and since I have been maintain this radiation the equivalent of about 10004stars (the Interested in R136 for a long time, I started to consider the hottest stars known have spectral type 03) are required. -
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 -
Dissecting the Core of the Tarantula Nebula with MUSE
Astronomical Science DOI: 10.18727/0722-6691/5053 Dissecting the Core of the Tarantula Nebula with MUSE Paul A. Crowther1 firmed as Lyman continuum leakers (for ute mosaic which encompasses both Norberto Castro2 example, Micheva et al., 2017). the R136 star cluster and R140 (an aggre- Christopher J. Evans3 gate of WR stars to the north). See Fig- Jorick S. Vink4 The Tarantula Nebula is host to hundreds ure 1 for a colour-composite of the cen- Jorge Melnick5 of massive stars that power the strong tral 200 × 160 pc of the Tarantula Nebula Fernando Selman5 Hα nebular emission, comprising main obtained with the Advanced Camera sequence OB stars, evolved blue super- for Surveys (ACS) and the Wide Field giants, red supergiants, luminous blue Camera 3 (WFC3) aboard the HST. The 1 Department of Physics & Astronomy, variables and Wolf-Rayet (WR) stars. The resulting image resolution spanned 0.7 University of Sheffield, United Kingdom proximity of the LMC (50 kpc) permits to 1.1 arcseconds, corresponding to a 2 Department of Astronomy, University of individual massive stars to be observed spatial resolution of 0.22 ± 0.04 pc, pro- Michigan, Ann Arbor, USA under natural seeing conditions (Evans viding a satisfactory extraction of sources 3 UK Astronomy Technology Centre, et al., 2011). The exception is R136, the aside from R136. Four exposures of Royal Observatory, Edinburgh, United dense star cluster at the LMC’s core that 600 s each for each pointing provided a Kingdom necessitates the use of adaptive optics yellow continuum signal-to-noise (S/N) 4 Armagh Observatory, United Kingdom or the Hubble Space Telescope (HST; see ≥ 50 for 600 sources. -
Super Star Cluster R136: Puzzles Outside and Inside
Super star cluster R136: puzzles outside and inside Sambaran Banerjee with Pavel Kroupa and Seungkyung Oh Argelander-Institut für Astronomie, University of Bonn @ “Aarseth N-body meeting in Bonn” Dec. 3-5, 2012 Super-cluster R136: a magnificent gallery of massive stars 30 Doradus (Tarantula Nebula) and R136 cluster in the LMC. Image credit: ESO Puzzle outside: • Speeding massive stars (e.g. 30 Dor 016) • “Slow runaway”s / isolated massive star formation? (e.g. VFTS 682) Puzzle inside: “Monster star”s: most massive star discovered so far! (M 300 M ) • ≈ • R136 in virial equilibrium. No gas expulsion? Runaway massive stars from R136 Puzzle outside: “slow runaway” star VFTS 682 VFTS 682 estimates Present day mass: 150 M Projected distance: 30 pc 1 3D velocity: 40 km S− (Bestenlehner et al. 2011) No bow-shock detected Image Credit: ESO/VISTA Magellanic Cloud survey Another runaway: 30 Dor 016 Estimates: PD mass 90 M ; projected distance 120 pc ; 1 velocity (3D) 150 km S − (Evans et al. 2010, ApJ, 715, L74) “Super-elastic” encounter The most likely result of a binary---single-star close encounter: hard binary hardens (Heggie’s law) Both intruder star & binary get recoiled with larger total K.E. Hard binary energy source Launches runaway stars ⇒ Image not to scale V. V. Gvaramadze et al.: Bow shocks around young star clusters. II. N N E E 2 arcmin 2 arcmin Fig. 3. Left:MSX21.3µmimageofbowshock2.Right:DSS-II(red Fig. 6. Left:MSX21.3µmimageofbowshock5.Right:DSS-II(red band) image of the same field. The position of the bow-shock-producing band) image of the same field. -
REFEREED PUBLICATIONS of YOU-HUA CHU A. Articles in Journals
REFEREED PUBLICATIONS OF YOU-HUA CHU A. Articles in Journals 1. Heiles, C., and Chu, Y.-H. 1980, “The Magnetic Field Strength in the H II Region S232,” ApJ, 235, L105-L109. 2. Chu, Y.-H., and Lasker, B.M. 1980, “Ring Nebulae Associated with Wolf-Rayet Stars in the Large Magellanic Cloud,” PASP, 92, 730-735. [Erratum: 1981, PASP, 93, 163] 3. Heiles, C., Chu, Y.-H., Reynolds, R.J., Yegingil, I., and Troland, T.H. 1980, “A New Look at the North Polar Spur,” ApJ, 242, 533-540. 4. Chu, Y.-H. 1981, “Galactic Ring Nebulae Associated with Wolf-Rayet Stars. I. Introduction and Classification,” ApJ, 249, 195-200. 5. Chu, Y.-H., and Treffers, R.R. 1981, “Galactic Ring Nebulae Associated with Wolf-Rayet Stars. III. H II Region-Type Nebulae,” ApJ, 250, 615-620. 6. Heiles, C., Chu, Y.-H., and Troland, T.H. 1981, “Magnetic Field Strengths in the H II Regions S117, S119, and S264,” ApJ, 247, L77-L80. 7. Chu, Y.-H., and Treffers, R.R. 1981, “Galactic Ring Nebulae Associated with Wolf-Rayet Stars. II. M1-67: A Nebula Braked by the Interstellar Medium,” ApJ, 249, 586-591. 8. Treffers, R.R., and Chu, Y.-H. 1982, “Galactic Ring Nebulae Associated with Wolf-Rayet Stars. VII. The Nebula G2.4+1.4,” ApJ, 254, 132-135. 9. Chu, Y.-H., Gull, T.R., Treffers, R.R., Kwitter, K.B., and Troland, T.H. 1982, “Galactic Ring Nebulae Associated with Wolf-Rayet Stars. IV. The Ring Nebula S308 and its Interstellar Environment,” ApJ, 254, 562-568. -
The Most Massive LMC Star Sk-66°41 Resolved
The Most Massive LMC Star Sk-66°41 Resolved M. HEYOARI-MALA YERI, ESO 1 Introduction of the dark lane. The star Iying at - 15" as we will see below. Wo 600 and Wo SE of Sk-66°41, called Wo 599 647 are late-type Galactic stars. N 11 C The upper limit to stellar masses con (Woolley, 1963), is of particular interest is a very young region, as shown by the stitutes one of the fundamental prob lems of astrophysics. Here I want to deal with Sk-66°41 (Sanduleak, 1969, other designation: HDE 268743), one of the most massive stars in the Large Magellanic Cloud. Sk-66°41, with its bolometric magnitude of -11 .2, appears at the second position (along with HDE 269698) in the list of the most luminous stars in the LMC compiled by Hum phreys (1983). As you may know from the ESO Press Release of last May 19, we have shown that Sk-66°41 is not a single star but a compact cluster of at least six components. This result has important implications for star formation theories and the distance scale in the Universe. This is a serious evidence against the existence of stars above 100 MG' The Associated H 11 Region N 11 C We got interested in Sk-66°41 dur ing our analysis of an H 11 region in the Wo 600 LMC as apart of the search and investi gation of the high excitation compact SK-66°41 HIlblobs in the Magellanic Clouds. The knowledge of the physical characteris tics of the associated H I1 region N 11 C (Henize, 1956) is important for under standing the nature of Sk-66°41. -
The VLT FLAMES Tarantula Survey
Astronomical Science The VLT FLAMES Tarantula Survey Chris Evans1 7 School of Physics, University of Exeter, high quality survey of extragalactic William Taylor2 United Kingdom massive stars ever assembled, and Hugues Sana3 8 ESO is already providing exciting new Vincent Hénault-Brunet2 9 Harvard–Smithsonian Center for Astro insights into their evolution, multiplicity Tullio Bagnoli3 physics, Cambridge, USA and formation. Nate Bastian4 10 Department of Astronomy, University of Joachim Bestenlehner5 Vienna, Austria Alceste Bonanos6 11 ArgelanderInstitut für Astronomie der Massive stars and their descendants Eli Bressert7, 8, 9 Universität Bonn, Germany dominate the dynamics and chemical Ines Brott10 12 Department of Physics and Astronomy, enrichment of young starforming gal Michael Campbell2 The Open University, Milton Keynes, axies, through their intense winds, radia Matteo Cantiello11 United Kingdom tion fields and dramatic deaths as core- Giovanni Carraro8 13 Departamento de Astronomia, Univer collapse supernovae. An overarching Simon Clark12 sidad de Chile, Santiago, Chile goal for studies of stellar evolution and Edgardo Costa13 14 Department. of Physics & Astronomy, resolved stellar populations is to develop Paul Crowther14 University of Sheffield, United Kingdom realistic tools to analyse integratedlight Alex de Koter3, 15 15 University of Utrecht, the Netherlands observations of distant star clusters Selma de Mink16, 17 16 Space Telescope Science Institute, and galaxies; if we can understand the Emile Doran14 Baltimore, USA properties and behaviour of the stars Philip Dufton18 17 Hubble Fellow on our own doorstep, we can be more Paul Dunstall18 18 Department of Physics & Astronomy, confident of an accurate interpretation of Miriam Garcia19, 20 Queen’s University Belfast, Northern unresolved populations far away. -
A Complete Massive Star Census of R136/NGC2070: the Core of 30
A complete massive star census of R136/NGC 2070: the core of 30 Doradus Joachim M. Bestenlehner1, Paul A. Crowther1, Saida M. Caballero-Nieves2, Sergio Simon-D´ ´ıaz3, Fabian R.N. Schneider4 10 September 2019 1University of Sheffield, 2Florida Institute of Technology, 3Instituto de Astrof´ısica de Canarias, 4University of Heidelberg 1 Outline R136 Data and analysis Masses and Ages Feedback He abundances and stellar winds Future massive star surveys (Stellar wind theory) 2 30 Doradus, NGC 2070 and R136 3 The star cluster R136 Stellar mass of 105 M ∼ Metallicity of 50% Z ∼ WNh, Of/WN and O stars 7.0 WNh-stars 6.5 6.0 O-stars ! L 5.5 / WR-stars L log 5.0 4.5 4.0 5.0 4.9 4.8 4.7 4.6 4.5 log Teff 4 R136: HST/STIS programme Crowther et al. 2016 39 HST orbits during Cycles 19-20 (17 STIS 52 0:2" slits) × 5 R136: HST/STIS programme Spectroscopic data (stellar parameters and chemical abundances): UV: HST/STIS 1180 to 1700 A˚ (G140L) blue-optical: HST/STIS 3800 to 4800 A˚ (G430M) Hα: HST/STIS 6300 to 6865 A˚ (G750M) Photometric data (luminosity and reddening): HST/WFC3: B-band (F438W) and V-band (F555W), de Marchi et al. (2011) VLT/SPHERE: K-band, Khorrami et al. (2017) HST/WFPC2: U (F336W) and V (F555W) photometry, Hunter et al. (1995) 6 Spectroscopic analysis: HSH95-31 FASTWIND analysis (Puls et al. (1995)) to be comparable with VLT/Flames Tarantula Survey (Evans et al. (2011)) CMFGEN analysis (Hillier & Miller (1998)) for R136a1, a2, a3 Reddening law from Ma´ız Apellaniz´ et al. -
The Star-Forming Complex LMC-N79 As a Future Rival to 30 Doradus
The star-forming complex LMC-N79 as a future rival to 30 Doradus Bram B. Ochsendorf1;∗, Hans Zinnecker2;3, Omnarayani Nayak1, John Bally4, Margaret Meixner1;5, Olivia C. Jones5, Remy Indebetouw6;7 & Mubdi Rahman1 1Department of Physics and Astronomy, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA, [email protected] 2Deutsches SOFIA Institut (DSI), University of Stuttgart, Pfaffenwaldring 29, D-70569, Germany 3Universidad Autonoma de Chile, Santiago de Chile, Chile 4Astrophysical and Planetary Sciences Department, University of Colorado, UCB 389 Boulder, Colorado 80309, USA 5Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA 6Department of Astronomy, University of Virginia, PO 400325, Charlottesville, VA 22904, USA 7National Radio Astronomy Observatory, 520 Edgemont Rd, Charlottesville, VA 22903, USA Within the early Universe, ‘extreme’ star formation may have been the norm rather than the 1, 2 5 exception . Super Star Clusters (SSCs; M? & 10 M ) are thought to be the modern-day analogs of globular clusters, relics of a cosmic time (z & 2) when the Universe was filled with vigorously star-forming systems3. The giant HII region 30 Doradus in the Large Magellanic Cloud (LMC) is often regarded as a benchmark for studies of extreme star formation4. Here, we report the discovery of a massive embedded star forming complex spanning ∼ 500 pc in the unexplored southwest region of the LMC, which manifests itself as a younger, embedded twin of 30 Doradus. Previously known as N79, this region has a star formation efficiency exceeding that of 30 Doradus by a factor of ∼ 2 as measured over the past .