Crowther, Paul A, Bibby, Joanne L, Furness, James P, Clark, J Simon
We highlight how the downward revision in the distance to the star cluster associated with SGR 1806-20 by Bibby et al. reconciles the apparent low contamination of BATSE short GRBs by intense flares...
Paul A. Crowther, Lucy J. Hadfield
Wolf-Rayet (WR) stars are the chemically evolved descendents of O stars, such that they trace massive star formation. Here we present results of recent VLT/FORS surveys of WR stars in near-by spiral...
On the central ionizing star of G23.96+0.15 and near-IR spectral classification of O stars (2008)
Crowther, Paul A, Furness, James P
Aims: A near-infrared study of the main ionizing star of the ultracompact HII region G23.96+0.15 (IRAS 18317-0757) is presented, along with a re-evaluation of the distance to this source, and a...
Westerlund 1 as a Template for Massive Star Evolution (2008)
Negueruela, Ignacio, Clark, J. Simon, Crowther, Paul A., Hadfield, Lucy
With a dynamical mass M_dyn ~ 1.3x10e5 M_sun and a lower limit M_cl>5x10e4 M_sun from star counts, Westerlund 1 is the most massive young open cluster known in the Galaxy and thus the perfect...
Andre Maeder & Philippe Eenens, eds. CNO Abundances in Magellanic Cloud OB Supergiants (2007)
Paul A. Crowther, Christopher J. Evans
Abstract. We present CNO abundance determinations in 11 Magellanic Cloud O and early B supergiants based on physical parameters obtained from FUSE, HST/IUE and VLT spectroscopy, plus model...
Progress in model atmosphere studies of Wolf-Rayet stars (2007)
G. Koenigsberger, Paul A. Crowther
Abstract. Recent progress in the quantitative analysis of Wolf-Rayet stars is reviewed, emphasising the role played by choice of spectral diagnostics, clumping and line-blanketing on derived stellar...
A&A manuscript no. (will be inserted by hand later) Your thesaurus codes are:
The Neon Abundance in WC stars II. ISO/SWS Spectroscopy of HD 156385 (WR90) (2007)
Luc Dessart, Allan J. Willis, Paul A. Crowther, D. John Hillier
In general, observationally derived wind compositions of WR stars are in reasonable agreement with predictions from stellar evolution models for massive stars. However, Barlow et al. (1988)...
The stellar content of the WR galaxy NGC5253 from ISO/SWS spectroscopy (2007)
Paul A. Crowther, Sara C. Beck, Allan J. Willis, Peter S. Conti, Patrick W. Morris, Ralph S. Sutherland
1. Why mid-IR spectroscopy of WR galaxies? Wolf-Rayet (WR) galaxies are a subset of blue emission-line galaxies whose spectra show the signature of large numbers of WR stars with ages in the range
Stellar properties of Galactic Centre He i sources (2007)
Luc Dessart, Paul A. Crowther, Linda J. Smith, Bruce Bohannan
The Galactic Centre (GC) region has recently attracted a lot of attention from the hot star community following the discovery of numerous He i emission line sources (Krabbe et al. 1991). Recent...
A Massive Star Odyssey, from Main Sequence to Supernova (2007)
Proceedings Iau Symposium, Paul A. Crowther, J. B. Abbott, L. Drissen, H. Schild, W. Schmutz, ...
We present new narrow-band imaging and optical spectroscopy of Wolf-Rayet stars in the Local Group dwarf galaxy IC10 (Gemini-N GMOS) and Sculptor group spiral galaxy NGC300 (VLT FORS2).
A Massive Star Odyssey, from Main Sequence to Supernova (2007)
Proceedings Iau Symposium, A. Herrero, C. Esteban, Christopher J. Evans, Paul A. Crowther, ...
We present results from optical and ultraviolet analysis of nine LMC/SMC supergiants. Temperatures, mass-loss rates and CNO abundances are obtained using the non-LTE, line-blanketed model atmosphere...
A Massive Star Odyssey, from Main Sequence to Supernova (2007)
Proceedings Iau Symposium, Linda J. Smith, Paul A. Crowther
Recent advances in atmosphere codes now permit the calculation of realistic grids of hot star atmospheres. Here we use the new O and WR star atmosphere of Smith, Norris & Crowther (2002) with an...
Physical and Wind Properties of [WC] Stars (2007)
We review the properties of carbon-sequence ([WC]) Wolf-Rayet central stars of planetary nebulae (CSPNe). Differences between the subtype distribution of [WC] stars and their massive WC cousins are...
Hot Massive Stars: The Impact of HST (2007)
We review the contribution of Hubble Space Telescope to the study of hot, luminous stars. Optical and IR imaging have permitted spatially resolved observations of young, massive clusters within Local...
On the optical counterpart of NGC300 X-1 and the global Wolf-Rayet content of NGC300 (2007)
Crowther, Paul A, Carpano, S., Hadfield, L. J., Pollock, A. M. T.
(Conext:) Surveys of Wolf-Rayet (WR) populations in nearby galaxies provide tests of evolutionary models plus Type Ib/c supernova progenitors. This spectroscopic study complements the recent imaging...
Physical Properties of Wolf-Rayet Stars (2006)
The striking broad emission line spectroscopic appearance of Wolf-Rayet (WR) stars has long defied analysis, due to the extreme physical conditions within their line and continuum forming regions....
Crowther, Paul A., Hadfield, L. J., Clark, J. S., Negueruela, I., Vacca, W. D.
New NTT/SOFI imaging and spectroscopy of the Wolf-Rayet population in Westerlund 1 are presented. Narrow-band near-IR imaging together with follow up spectroscopy reveals four new WR stars, of which...
Metallicity Dependent Wolf-Rayet Winds (2006)
Observational and theoretical evidence in support of metallicity dependent winds for Wolf-Rayet stars is considered. Well known differences in Wolf-Rayet subtype distributions in the Milky Way, LMC...
Reduced Wolf-Rayet Line Luminosities at Low Metallicity (2005)
Crowther, Paul A, Hadfield, L J
New NTT/EMMI spectrophotometry of single WN2-5 stars in the Magellanic Clouds are presented, from which HeII 4686 line luminosities have been derived, and compared with observations of other...
Observed Metallicity Dependence of Winds from WR stars (2005)
A review of observational evidence in favour of a metallicity dependence of WN and WC stars is presented. New near-IR studies of Milky Way, LMC and SMC early-type WN stars are presented, with weake...
Properties of Hot, Massive Stars: The Impact of FUSE (2004)
The impact of FUSE upon the fundamental parameters of OB stars and Wolf-Rayet stars is reviewed. The stellar wind signatures available in the far-UV provide us with important additional diagnostics...
A CNO Dichotomy among O2 Giant Spectra in the Magellanic Clouds (2004)
Walborn, Nolan R., Morrell, Nidia I., Howarth, Ian D., Crowther, Paul A., Lennon, Daniel J., Massey, Philip, ...
From a survey of the 3400 A region in the earliest O-type spectra, we have found that two of the four O2 giants observed in the LMC have the OIV lines there stronger than the NIV, while the other two...
Wolf-Rayet stars in M33 - I. Optical spectroscopy using CFHT-MOS (2004)
Abbott, B., Crowther, Paul A., Drissen, Laurent, Dessart, Luc, Martin, Pierre, Boivin, Guillaume
MSX Mid infrared imaging of massive star birth environments. II: Giant HII regions (2003)
Conti, Peter S, Crowther, Paul A.
We conduct a Galactic census of Giant HII regions, based on the all sky 6cm dataset of Kuchar & Clark, plus the kinematic distances obtained by Russeil. From an inspection of mid-IR Mid-course Space...
Fundamental Parameters of Massive Stars (2003)
We discuss the determination of fundamental parameters of `normal' hot, massive OB-type stars, namely temperatures, luminosities, masses, gravities and surface abundances. We also present methods...
Massive Stars in Transition (2003)
We discuss the various post-main sequence phases of massive stars, focusing on Wolf-Rayet stars, Luminous Blue Variables, plus connections with other early-type and late-type supergiants. End states...
MSX Mid Infrared Imaging of Massive Star Birth Environments. I: Ultracompact HII Regions (2003)
Crowther, Paul A., Conti, Peter S.
We present mid-IR 21micron images of a sample of radio selected Ultracompact HII (UCHII) regions, obtained with the Midcourse Space Experiment (MSX). All, with one possible exception, are detected at...
Stellar Parameters of Wolf-Rayet Stars from Far-UV to Mid-IR Observations (2002)
Recent results for Galactic and Magellanic Cloud Wolf-Rayet stars are summarised based on line blanketed, clumped model atmospheres together with UV, optical and IR spectroscopy. The trend towards...
Realistic Ionizing Fluxes for Young Stellar Populations from 0.05 to twice solar metallicity (2002)
Smith, Linda J., Norris, Richard P. F., Crowther, Paul A.
We present a new grid of ionizing fluxes for O and Wolf-Rayet stars for use with evolutionary synthesis codes and single star H II region analyses. A total of 230 expanding, non-LTE, line-blanketed...
Crowther, Paul A., Dessart, Luc, Hillier, D. John, Abbott, Jay B., Fullerton, Alex W.
We use ultraviolet space-based (FUSE, HST) and optical/IR ground-based (2.3m MSSSO, NTT) spectroscopy to determine the physical parameters of six WC4-type Wolf-Rayet stars in the Large Magellanic...
MSX mid infrared imaging of massive star birth environments. I: Ultracompact H-II regions (2002)
Paul A. Crowther, Peter S. Conti
We present mid-IR 21m images of a sample of radio selected Ultracompact H ii (UCH ii) regions, obtained with the Midcourse Space Experiment (MSX). All, with one possible exception, are detected at...
A FUSE Survey of Interstellar Molecular Hydrogen in the Small and Large Magellanic Clouds (2001)
Tumlinson, Jason, Shull, J. Michael, Rachford, Brian L., Browning, Matthew K., Snow, Theodore P., Fullerton, Alex W., ...
We describe a moderate-resolution FUSE survey of H2 along 70 sight lines to the Small and Large Magellanic Clouds, using hot stars as background sources. FUSE spectra of 67% of observed Magellanic...
Stellar winds from Massive Stars (2000)
We review the various techniques through which wind properties of massive stars - O stars, AB supergiants, Luminous Blue Variables (LBVs), Wolf-Rayet (WR) stars and cool supergiants - are derived....
Far-UV FUSE spectroscopy of the OVI resonance doublet in Sand2 (WO) (2000)
Crowther, Paul A., Fullerton, A. W., Hillier, D. J., Brownsberger, K., Dessart, L., Willis, A. J., ...
We present Far-Ultraviolet Spectroscopic Explorer (FUSE) spectroscopy of Sand 2, a LMC WO-type Wolf-Rayet star, revealing the OVI resonance P Cygni doublet at 1032-38A. These data are combined with...
Wind properties of Wolf-Rayet stars at low metallicity: Sk41 (SMC) (2000)
The stellar properties of Sk41 (AB4, WN5h), the only known single Wolf-Rayet star in the SMC, are derived from ultraviolet (IUE), optical (AAT) and near-IR (NTT) spectroscopy. Contrary to...
Quantitative analysis of WC stars: Constraints on neon abundances from ISO/SWS spectroscopy (2000)
Dessart, Luc, Crowther, Paul A., Hillier, D. John, Willis, Allan J., Morris, Patrick W., Van Der Hucht, Karel A.
Neon abundances are derived in four Galactic WC stars -- gamma Vel (WR11, WC8+O7.5III), HD156385 (WR90, WC7), HD192103 (WR135, WC8), and WR146 (WC5+O8) - using mid-infrared fine structure lines...
NaSt1: A Wolf-Rayet star cloaked by an eta Car--like nebula? (1999)
Crowther, Paul A., Smith, Linda J.
We present a study of the peculiar Galactic emission line object NaSt1 (WR122, IRAS 18497+0056) which has previously been classified as a Wolf-Rayet (WR) star. Our spectroscopic dataset comprises...
M4-18: The planetary nebula and its WC10 central star (1999)
De Marco, Orsola, Crowther, Paul A.
We present a detailed analysis of the planetary nebula M4-18 (G146.7+07.6) and its WC10-type Wolf-Rayet central star, based on high quality optical spectroscopy (WHT/UES, INT/IDS, WIYN/DensPak) and...
Progress in Model Atmosphere Studies of Wolf-Rayet stars (1998)
Recent progress in the quantitative analysis of Wolf-Rayet stars is reviewed, emphasising the role played by choice of spectral diagnostics, clumping and line blanketing on derived stellar...
Properties of Hot Stars in the Wolf-Rayet galaxy NGC5253 from ISO Spectroscopy (1998)
Crowther, Paul A., Beck, S. C., Willis, Allan J., Conti, Peter S., Morris, Pat W., Sutherland, Ralph S.
ISO-SWS spectroscopy of the WR galaxy NGC5253 is presented, and analysed to provide estimates of its hot young star population. Our approach differs from previous investigations in that we are able...