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

被引：180

作者：

Crowther, Paul A. ^{[1
]}

Caballero-Nieves, S. M. ^{[1
]}

Bostroem, K. A. ^{[2
,3
]}

Maiz Apellaniz, J. ^{[4
]}

Schneider, F. R. N. ^{[5
,6
]}

Walborn, N. R. ^{[2
]}

Angus, C. R. ^{[1
,7
]}

Brott, I. ^{[8
]}

Bonanos, A. ^{[9
]}

de Koter, A. ^{[10
,11
]}

de Mink, S. E. ^{[10
]}

Evans, C. J. ^{[12
]}

Grafener, G. ^{[13
]}

Herrero, A. ^{[14
,15
]}

Howarth, I. D. ^{[16
]}

Langer, N. ^{[6
]}

Lennon, D. J. ^{[17
]}

Puls, J. ^{[18
]}

Sana, H. ^{[2
,11
]}

Vink, J. S. ^{[13
]}

机构：

[1] Univ Sheffield, Dept Phys & Astron, Sheffield S3 7RH, S Yorkshire, England

[2] Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA

[3] Univ Calif Davis, Dept Phys, 1 Shields Ave, Davis, CA 95616 USA

[4] CSIC, INTA, Ctr Astrobiol, Campus ESAC,Apartado Postal 78, E-28691 Madrid, Spain

[5] Univ Oxford, Dept Phys, Denys Wilkinson Bldg,Keble Rd, Oxford OX1 3RH, England

[6] Univ Bonn, Argelanger Inst Astron, Hugel 71, D-53121 Bonn, Germany

[7] Univ Warwick, Dept Phys, Gibbet Hill Rd, Coventry CV4 7AL, W Midlands, England

[8] Inst Astrophys, Tuerkenschanzstr 17, A-1180 Vienna, Austria

[9] Natl Observ Athens, Inst Astron & Astrophys, I Metaxa & Vas Pavlou St, Palea Penteli 15236, Greece

[10] Univ Amsterdam, Astron Inst Anton Pannekoek, Kruislaan 403, NL-1098 SJ Amsterdam, Netherlands

[11] Katholieke Univ Leuven, Inst Astron, Celestijnenlaan 200 D, B-3001 Leuven, Belgium

[12] Royal Observ, UK Astron Technol Ctr, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland

[13] Armagh Observ, Coll Hill, Armagh BT61 9DG, North Ireland

[14] Inst Astrofis Canarias, E-38200 Tenerife, Spain

[15] Univ La Laguna, Dept Astrofis, E-38205 Tenerife, Spain

[16] UCL, Dept Phys & Astron, Gower St, London WC1E 6BT, England

[17] ESA, European Space Astron Ctr, Madrid, Spain

[18] Univ Sternwarte, Scheinerstr 1, D-81679 Munich, Germany

来源：

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | 2016年 / 458卷 / 01期

基金：

英国科学技术设施理事会;

关键词：

stars: early-type; stars: massive; stars:; winds; outflows; Magellanic Clouds; galaxies: star clusters: individual: R136a; O-TYPE STARS; LARGE-MAGELLANIC-CLOUD; WOLF-RAYET STARS; EFFECTIVE TEMPERATURE SCALE; OPTICAL SPECTRAL MORPHOLOGY; INITIAL MASS FUNCTION; 30; DORADUS; PHYSICAL-PROPERTIES; MAIN-SEQUENCE; TERMINAL VELOCITIES;

D O I：

10.1093/mnras/stw273

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We introduce a Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph (STIS) stellar census of R136a, the central ionizing star cluster of 30 Doradus. We present low resolution far-ultraviolet STIS spectroscopy of R136 using 17 contiguous 52 arcsec x 0.2 arcsec slits which together provide complete coverage of the central 0.85 parsec (3.4 arcsec). We provide spectral types of 90 per cent of the 57 sources brighter than m(F555W) = 16.0 mag within a radius of 0.5 parsec of R136a1, plus 8 additional nearby sources including R136b (O4 If/WN8). We measure wind velocities for 52 early-type stars from C IV lambda lambda 1548-51, including 16 O2-3 stars. For the first time, we spectroscopically classify all Weigelt and Baier members of R136a, which comprise three WN5 stars (a1-a3), two O supergiants (a5-a6) and three early O dwarfs (a4, a7, a8). A complete Hertzsprung-Russell diagram for the most massive O stars in R136 is provided, from which we obtain a cluster age of 1.5(-0.7)(+0.3) Myr. In addition, we discuss the integrated ultraviolet spectrum of R136, and highlight the central role played by the most luminous stars in producing the prominent He II lambda 1640 emission line. This emission is totally dominated by very massive stars with initial masses above similar to 100M(circle dot). The presence of strong He II lambda 1640 emission in the integrated light of very young star clusters (e.g. A1 in NGC 3125) favours an initial mass function extending well beyond a conventional upper limit of 100M(circle dot). We include montages of ultraviolet spectroscopy for Large Magellanic Cloud O stars in the appendix. Future studies in this series will focus on optical STIS medium resolution observations.

引用

页码：624 / 659

页数：36

共 102 条

[1] THE LOW-MASS INITIAL MASS FUNCTION IN THE 30 DORADUS STARBURST CLUSTER [J].

Andersen, M. ;

Zinnecker, H. ;

Moneti, A. ;

McCaughrean, M. J. ;

Brandl, B. ;

Brandner, W. ;

Meylan, G. ;

Hunter, D. .

ASTROPHYSICAL JOURNAL, 2009, 707 (02) :1347-1360

[2] The emergence of super-canonical stars in R136-type starburst clusters [J].

Banerjee, Sambaran ;

Kroupa, Pavel ;

Oh, Seungkyung .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2012, 426 (02) :1416-1426

[3] The VLT-FLAMES Tarantula Survey XVII. Physical and wind properties of massive stars at the top of the main sequence [J].

Bestenlehner, J. M. ;

Graefener, G. ;

Vink, J. S. ;

Najarro, F. ;

de Koter, A. ;

Sana, H. ;

Evans, C. J. ;

Crowther, P. A. ;

Henault-Brunet, V. ;

Herrero, A. ;

Langer, N. ;

Schneider, F. R. N. ;

Simon-Diaz, S. ;

Taylor, W. D. ;

Walborn, N. R. .

ASTRONOMY & ASTROPHYSICS, 2014, 570

[4] The VLT-FLAMES Tarantula Survey III. A very massive star in apparent isolation from the massive cluster R136 [J].

Bestenlehner, J. M. ;

Vink, J. S. ;

Graefener, G. ;

Najarro, F. ;

Evans, C. J. ;

Bastian, N. ;

Bonanos, A. Z. ;

Bressert, E. ;

Crowther, P. A. ;

Doran, E. ;

Friedrich, K. ;

Henault-Brunet, V. ;

Herrero, A. ;

de Koter, A. ;

Langer, N. ;

Lennon, D. J. ;

Maiz Apellaniz, J. ;

Sana, H. ;

Soszynski, I. ;

Taylor, W. D. .

ASTRONOMY & ASTROPHYSICS, 2011, 530

[5]

Bostroem K. A., 2011, STIS DATA HDB V6 0

[6] Rotating massive main-sequence stars I. Grids of evolutionary models and isochrones [J].

Brott, I. ;

de Mink, S. E. ;

Cantiello, M. ;

Langer, N. ;

de Koter, A. ;

Evans, C. J. ;

Hunter, I. ;

Trundle, C. ;

Vink, J. S. .

ASTRONOMY & ASTROPHYSICS, 2011, 530

[7] VLT-MAD observations of the core of 30 Doradus [J].

Campbell, M. A. ;

Evans, C. J. ;

Mackey, A. D. ;

Gieles, M. ;

Alves, J. ;

Ascenso, J. ;

Bastian, N. ;

Longmore, A. J. .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2010, 405 (01) :421-435

[8] CENTRAL OBJECT OF THE 30-DORADUS NEBULA, A SUPERMASSIVE STAR [J].

CASSINELLI, JP ;

MATHIS, JS ;

SAVAGE, BD .

SCIENCE, 1981, 212 (4502) :1497-1501

[9] NGC 3125-1: The most extreme Wolf-Rayet star cluster known in the local universe [J].

Chandar, R ;

Leitherer, C ;

Tremonti, CA .

ASTROPHYSICAL JOURNAL, 2004, 604 (01) :153-166

[10] ON WINDS AND X-RAYS OF O-TYPE STARS [J].

CHLEBOWSKI, T ;

GARMANY, CD .

ASTROPHYSICAL JOURNAL, 1991, 368 (01) :241-251

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