132 citations · 990 across the 34 of their papers we have counts for
27 papers · 1 filter
The Treasury of Extremely Metal-Poor O Stars
O. Grace Telford, Christiana Erba, Kristen B. W. McQuinn +10
The Treasury of Extremely Metal-Poor O Stars (TEMPOS) is a Hubble Space Telescope survey of hot and massive O-type stars in nearby, low-metallicity galaxies (20% of the s…
SpecFANN: Spectral Fitting via Artificial Neural Networks I. A deep learning based fastwind emulator and fitting suite
M. Abdul-Masih, C. Hawcroft, T. Lechien +14
The importance of massive stars cannot be overstated: they are powerful probes of the early universe, play a vital role in the chemical and mechanical evolution of their host envir…
Stellar winds of O-type stars traced by high ionization fine-structure emission lines with JWST/MIRI
Calum Hawcroft, David R. Law, Linda J. Smith +8
We investigate the presence of high ionization fine-structure emission lines across a range of 22 OB-type stars observed with JWST-MIRI as part of calibration programmes and the WI…
X-Shooting ULLYSES: Massive stars at low metallicity XV. On the metallicity dependence of B-supergiant mass-loss rates
O. Verhamme, J. O. Sundqvist, A. de Koter +21
Context. For stellar evolution models we rely on mass-loss rate prescriptions that show features that lack empirical confirmation, such as the bi-stability jump. This jump is an in…
Echoes of the First Stars: Massive Star Evolution in Extremely Metal-Poor Environments with the Habitable Worlds Observatory
Peter Senchyna, Calum Hawcroft, Miriam Garcia +3
A remarkable span of frontier astrophysics, from gravitational-wave archaeology to the origin of the elements to interpreting snapshots of the earliest galaxies, depends sensitivel…
A high fraction of close massive binary stars at low metallicity
H. Sana, T. Shenar, J. Bodensteiner +74
At high metallicity, a majority of massive stars have at least one close stellar companion. The evolution of such binaries is subject to strong interaction processes, heavily impac…
X-Shooting ULLYSES: massive stars at low metallicity: XII. The clumped winds of O-type (super)giants in the Large Magellanic Cloud
Sarah A. Brands, Frank Backs, Alex de Koter +23
Mass loss governs the evolution of massive stars and shapes the stellar surroundings. To quantify the impact of the stellar winds we need to know the exact mass-loss rates; however…
X-Shooting ULLYSES: Massive Stars at Low Metallicity: XI. Pipeline-determined Physical Properties of Magellanic Cloud OB Stars
J. M. Bestenlehner, P. A. Crowther, C. Hawcroft +5
The proximity & low dust extinction of the Magellanic Clouds provides an ideal environment for metal-poor massive stars to be studied in detail. The HST ULLYSES initiative has prov…
X-Shooting ULLYSES: Massive stars at low metallicity VI. Atmosphere and mass-loss properties of O-type giants in the Small Magellanic Cloud
Frank Backs, S. A. Brands, A. de Koter +21
Mass loss through a stellar wind is an important physical process that steers the evolution of massive stars and controls the properties of their end-of-life products, such as the…
JWST/MIRI detection of [Ne V], [Ne VI], and [O IV] wind emission in the O9V star 10 Lacertae
David R. Law, Calum Hawcroft, Linda J. Smith +5
We report the detection of broad, flat-topped emission in the fine-structure lines of [Ne V], [Ne VI], and [O IV] in mid-infrared spectra of the O9 V star 10 Lacertae obtained with…
X-Shooting ULLYSES: Massive stars at low metallicity VII. Stellar and wind properties of B supergiants in the Small Magellanic Cloud
M. Bernini-Peron, A. A. C. Sander, V. Ramachandran +22
Context. B supergiants (BSGs) represent an important connection between the main sequence and more extreme evolutionary stages of massive stars. Additionally, lying toward the cool…
Empirical mass-loss rates and clumping properties of O-type stars in the LMC
C. Hawcroft, L. Mahy, H. Sana +6
We constrain wind parameters of a sample of 18 O-type stars in the LMC, through analysis with stellar atmosphere and wind models including the effects of optically thick clumping.…
Binarity at LOw Metallicity (BLOeM): a spectroscopic VLT monitoring survey of massive stars in the SMC
T. Shenar, J. Bodensteiner, H. Sana +74
Surveys in the Milky Way and Large Magellanic Cloud revealed that the majority of massive stars will interact with companions during their lives. However, knowledge of the binary p…
X-Shooting ULLYSES: Massive Stars at low metallicity II. DR1: Advanced optical data products for the Magellanic Clouds
H. Sana, F. Tramper, M. Abdul-Masih +34
Using the medium resolution spectrograph X-shooter, spectra of 235 OB and Wolf-Rayet (WR) stars in sub-solar metallicity environments have been secured. [...]This second paper focu…
X-Shooting ULLYSES: massive stars at low metallicity. I. Project Description
Jorick S. Vink, A. Mehner, P. A. Crowther +78
Observations of individual massive stars, super-luminous supernovae, gamma-ray bursts, and gravitational-wave events involving spectacular black-hole mergers, indicate that the low…
X-Shooting ULLYSES: Massive stars at low metallicity. III. Terminal wind speeds of ULLYSES massive stars
C. Hawcroft, H. Sana, L. Mahy +26
The winds of massive stars have an impact on stellar evolution and on the surrounding medium. The maximum speed reached by these outflows, the terminal wind speed, is a global wind…
The Nature of Unseen Companions in Massive Single-Line Spectroscopic Binaries
Hugues Sana, Michael Abdul-Masih, Gareth Banyard +14
Massive stars are predominantly found in binaries and higher order multiples. While the period and eccentricity distributions of OB stars are now well established across different…
Identifying quiescent compact objects in massive Galactic single-lined spectroscopic binaries
L. Mahy, H. Sana, T. Shenar +13
Aims. To search for these rare objects, we study 32 Galactic O-type stars that were reported as SB1s in the literature. In our sample we include Cyg X-1, which is known to host an…
HR 6819 is a binary system with no black hole -- revisiting the source with infrared interferometry and optical integral field spectroscopy
A. J. Frost, J. Bodensteiner, Th. Rivinius +16
Two scenarios have been proposed to match the existing observational constraints of the object HR 6819. The system could consist of a close inner B-type giant plus a black hole (BH…
The R136 star cluster dissected with Hubble Space Telescope/STIS. III. The most massive stars and their clumped winds
Sarah A. Brands, Alex de Koter, Joachim M. Bestenlehner +17
Context: The star cluster R136 inside the LMC hosts a rich population of massive stars, including the most massive stars known. The strong stellar winds of these very luminous star…
Empirical mass-loss rates and clumping properties of Galactic early-type O supergiants
C. Hawcroft, H. Sana, L. Mahy +7
We investigate the impact of optically thick clumping on stellar wind diagnostics in O supergiants and constrain wind parameters associated with porosity in velocity space. This is…
Resolving the dynamical mass tension of the massive binary 9 Sagittarii
M. Fabry, C. Hawcroft, A. J. Frost +4
Direct dynamical mass measurements of stars with masses above 30 M are rare. This is the result of the low yield of the upper initial mass function and the limited number…
Constraining the Overcontact Phase in Massive Binary Evolution I. Mixing in V382 Cyg, VFTS 352, and OGLE SMC-SC10 108086
Michael Abdul-Masih, Hugues Sana, Calum Hawcroft +10
As potential progenitors of several exotic phenomena including gravitational wave sources, magnetic stars, and Be stars, close massive binary systems probe a crucial area of the pa…
Characterization of the variability in the O+B eclipsing binary HD 165246
Cole Johnston, Nicolas Aimar, Michael Abdul-Masih +8
O-stars are known to experience a wide range of variability mechanisms originating at both their surface and their near-core regions. Characterization and understanding of this var…