Publications (154)
Wind-envelope interaction as the origin of the slow cyclic brightness variations of luminous blue variables
Luca Grassitelli, Norbert Langer, Jonathan Mackey +4
Luminous blue variables (LBVs) are hot, very luminous massive stars displaying large quasi-periodic variations in brightness, radius,and photospheric temperature, on timescales of…
Turbulence and magnetic spots at the surface of hot massive stars
Matteo Cantiello, Jonathan Braithwaite, Axel Brandenburg +3
Hot luminous stars show a variety of phenomena in their photospheres and in their winds which still lack clear physical explanations at this time. Among these phenomena are non-the…
Related progenitor models for long-duration gamma ray bursts and Type Ic superluminous supernovae
David R. Aguilera-Dena, Norbert Langer, Takashi J. Moriya +1
We model the late evolution and mass loss history of rapidly rotating Wolf-Rayet stars in the mass range . We find that quasi-chemically…
Cold gas in hot star clusters: the wind from the red supergiant W26 in Westerlund 1
Jonathan Mackey, Norberto Castro, Luca Fossati +1
The massive red supergiant (RSG) W26 in Westerlund 1 is one of a growing number of RSGs shown to have winds that are ionized from the outside in. The fate of this dense wind materi…
An X-ray quiet black hole born with a negligible kick in a massive binary within the Large Magellanic Cloud
Tomer Shenar, Hugues Sana, Laurent Mahy +35
Stellar-mass black holes are the final remnants of stars born with more than 15 solar masses. Billions are expected to reside in the Local Group, yet only few are known, mostly det…
Stabilization of helium shell burning by rotation in accreting white dwarfs
Sung-Chul Yoon, Norbert Langer
The currently favored scenario for the progenitor evolution of Type Ia supernovae (SNe Ia) presumes that white dwarfs in close binary systems grow to the Chandrasekhar limit via ma…
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…
Effects of close binary evolution on the main-sequence morphology of young star clusters
Chen Wang, Norbert Langer, Abel Schootemeijer +4
Star clusters are the building blocks of galaxies. They are composed of stars of nearly equal age and chemical composition, allowing us to use them as chronometers and as testbeds…
Stripped helium-star and compact object binaries in coeval populations -- predictions based on detailed binary evolution models
Chen Wang, Julia Bodensteiner, Xiao-Tian Xu +9
Massive stars mainly form in close binaries, where their mutual interactions can profoundly alter their evolutionary paths. Evolved binaries consisting of a massive OB-type main-se…
Three dimensional magnetorotational core-collapse supernova explosions of a 39 solar mass progenitor star
Jade Powell, Bernhard Mueller, David R. Aguilera-Dena +1
We perform three-dimensional simulations of magnetorotational supernovae using a progenitor star with two different initial magnetic field strengths of G…
A three-dimensional hydrodynamics simulation of oxygen-shell burning in the final evolution of a fast-rotating massive star
Takashi Yoshida, Tomoya Takiwaki, David R. Aguilera-Dena +5
We perform for the first time a 3D hydrodynamics simulation of the evolution of the last minutes pre-collapse of the oxygen shell of a fast-rotating massive star. This star has an…
The initial spin distribution of B-type stars revealed by the split main sequences of young star clusters
Chen Wang, Ben Hastings, Abel Schootemeijer +6
Spectroscopic observations of stars in young open clusters have revealed evidence for a dichotomous distribution of stellar rotational velocities, with 10-30% of stars rotating slo…
Evolution of wide O star binaries through their LBV stage. Population synthesis with mass-ejection-driven orbital evolution
Xiao-Tian Xu, Philipp Podsiadlowski, Norbert Langer +6
Context. Long-period Wolf-Rayet (WR) star binaries produced by mass transfer are predicted to be abundant, but are observationally rare. This yields constraints on the evolution of…
Standing torsional Alfvén waves as the source of the rotational period variation in magnetic early-type stars
Koh Takahashi, Norbert Langer
Context. The influence of magnetic fields on stellar evolution remains unresolved. It has been proposed that if there is a large-scale magnetic field in the stellar interior, torsi…
Envelope inflation in Wolf-Rayet stars and extended supernova shock breakout signals
Debashis Sanyal, Takashi J. Moriya, Norbert Langer
Massive, luminous stars reaching the Eddington limit in their interiors develop very dilute, extended envelopes. This effect is called envelope inflation. If the progenitors of Typ…
Massive main sequence stars evolving at the Eddington limit
Debashis Sanyal, Luca Grassitelli, Norbert Langer +1
The evolution of massive stars even on the main sequence is not yet well understood. Due to the steep mass-luminosity relation, massive main sequence stars become very luminous. Th…
Ultra-stripped supernovae: progenitors and fate
Thomas M. Tauris, Norbert Langer, Philipp Podsiadlowski
The explosion of ultra-stripped stars in close binaries can lead to ejecta masses < 0.1 M_sun and may explain some of the recent discoveries of weak and fast optical transients. In…
Type Ib/c supernovae in binary systems I. Evolution and properties of the progenitor stars
Sung-Chul Yoon, Stan E. Woosley, Norbert Langer
We investigate the evolution of Type Ib/c supernova (SN Ib/c) progenitors in close binary systems, using new evolutionary models that include the effects of rotation, with initial…
The s-process in rotating AGB stars
Falk Herwig, Norbert Langer, Maria Lugaro
We discuss the occurrence of the s-process during the radiative interpulse phase of rotating AGB stars. Due to differential rotation, protons are mixed into C12-rich layers after t…
Ultra-luminous X-ray sources and neutron-star-black-hole mergers from very massive close binaries at low metallicity
Pablo Marchant, Norbert Langer, Philipp Podsiadlowski +4
Gravitational waves from the binary black hole (BH) merger GW150914 may enlighten our understanding of ultra-luminous X-ray sources (ULXs), as BHs>30Msun can reach luminosities>4x1…
Thermal-timescale accretion does not always yield critical rotation in mass gainers
Chen Wang, Mike Y. M. Lau, Xiang-Dong Li +7
Binary evolution plays a central role in producing rapidly rotating stars. Previous studies have shown that mass gainers in binaries can reach critical rotation after accreting onl…
Supergiants and their shells in young globular clusters
Dorottya Szécsi, Jonathan Mackey, Norbert Langer
Anomalous surface abundances are observed in a fraction of the low-mass stars of Galactic globular clusters, that may originate from hot-hydrogen-burning products ejected by a prev…
Revealing the binary origin of Type Ic superluminous supernovae through nebular hydrogen emission
Takashi J. Moriya, Zheng-Wei Liu, Jonathan Mackey +2
We propose that nebular H-alpha emission as detected in the Type Ic superluminous supernova iPTF13ehe stems from matter which is stripped from a companion star when the supernova e…
Fallback supernova assembly of heavy binary neutron stars and light black hole-neutron star pairs and the common stellar ancestry of GW190425 and GW200115
Alejandro Vigna-Gómez, Sophie L. Schrøder, Enrico Ramirez-Ruiz +4
The detection of the unusually heavy binary neutron star merger GW190425 marked a stark contrast to the mass distribution from known Galactic pulsars in double neutron star binarie…
Metallicity dependence of turbulent pressure and macroturbulence in stellar envelopes
Luca Grassitelli, Luca Fossati, Norbert Langer +3
Macroturbulence, introduced as a fudge to reproduce the width and shape of stellar absorption lines, reflects gas motions in stellar atmospheres. While in cool stars, it is thought…
Runaway stars as progenitors of supernovae and gamma-ray bursts
John J. Eldridge, Norbert Langer, Christopher A. Tout
When a core collapse supernova occurs in a binary system, the surviving star as well as the compact remnant emerging from the SN, may reach a substantial space velocity. With binar…
Convective Core Overshoot & Mass Loss in Classical Cepheids: A Solution to the Mass Discrepancy?
Hilding R. Neilson, Matteo Cantiello, Norbert Langer
We explore the role of mass loss and convective core overshoot in the evolution of Classical Cepheids. Stellar evolution models are computed with a recipe for pulsation-driven mass…
Massive Binary Stars and Self-Enrichment of Globular Clusters
Robert G. Izzard, Selma E. de Mink, Onno R. Pols +3
Globular clusters contain many stars with surface abundance patterns indicating contributions from hydrogen burning products, as seen in the anti-correlated elemental abundances of…
Detailed evolutionary models of massive contact binaries: I. Model grids and synthetic populations for the Magellanic Clouds
Athira Menon, Norbert Langer, Selma E. de Mink +8
The majority of close massive binary stars with initial periods of a few days experience a contact phase, in which both stars overflow their Roche lobes simultaneously. We perform…
X-rays observations of a super-Chandrasekhar object reveal an ONeMg and a CO white dwarf merger product embedded in a putative SN Iax remnant
Lidia M. Oskinova, Vasilii V. Gvaramadze, Goetz Graefener +2
The merger of two white dwarfs (WD) is a natural outcome from the evolution of many binary stars. Recently, a WD merger product, IRAS 00500+6713, was identified. IRAS 00500+6713 co…
Is there a mass discrepancy in the Cepheid binary OGLE-LMC-CEP0227?
Hilding R. Neilson, Norbert Langer
Context. The Cepheid mass discrepancy, the difference between masses predicted from stellar evolution and stellar pulsation calculations, is a challenge for the understanding of st…
The detection of extragalactic N: Consequences for nitrogen nucleosynthesis and chemical evolution
Yi-nan Chin, Christian Henkel, Norbert Langer +1
Detections of extragalactic N are reported from observations of the rare hydrogen cyanide isotope HCN toward the Large Magellanic Cloud (LMC) and the core of the (pos…
Bridging the Gap: From Massive Stars to Supernovae
Justyn R. Maund, Paul A. Crowther, Hans-Thomas Janka +1
Almost since the beginning, massive stars and their resultant supernovae have played a crucial role in the Universe. These objects produce tremendous amounts of energy and new, hea…
Which Massive stars are Gamma-Ray Burst Progenitors?
Jelena Petrovic, Norbert Langer, Sung-Chul Yoon +1
The collapsar model for gamma-ray bursts requires three essential ingredients: a massive core, removal of the hydrogen envelope, and enough angular momentum in the core. We study c…
Modeling of Magneto-Rotational Stellar Evolution I. Method and first applications
Koh Takahashi, Norbert Langer
While magnetic fields have long been considered to be important for the evolution of magnetic non-degenerate stars and compact stars, it has become clear in recent years that actua…
BONNSAI: a Bayesian tool for comparing stars with stellar evolution models
Fabian R. N. Schneider, Norbert Langer, Alex de Koter +3
Powerful telescopes equipped with multi-fibre or integral field spectrographs combined with detailed models of stellar atmospheres and automated fitting techniques allow for the an…
Induced differential rotation and mixing in asynchronous binary stars
Gloria Koenigsberger, Edmundo Moreno, Norbert Langer
Rotation contributes to internal mixing processes and observed variability in massive stars. A significant number of binary stars are not in strict synchronous rotation, including…
Spectroscopic and physical parameters of Galactic O-type stars. III. Mass discrepancy and rotational mixing
Nevena Markova, Joachim Puls, Norbert Langer
Massive stars play a key role in the evolution of the Universe. Our goal is to compare observed and predicted properties of single Galactic O stars to identify and constrain uncert…
Boron Abundances in Early B Dwarfs of the Galactic Open Cluster NGC 3293
Charles R. Proffitt, Harim Jin, Simone Daflon +4
New boron abundances or upper limits have been determined for 8 early-B stars in the young Galactic open cluster NGC 3293, using ultraviolet spectra obtained by the Hubble Space Te…
3D Smoothed Particle Hydrodynamics Models of Betelgeuse's Bow Shock
Shazrene Mohamed, Jonathan Mackey, Norbert Langer
Betelgeuse, the bright red supergiant (RSG) in Orion, is a runaway star. Its supersonic motion through the interstellar medium has resulted in the formation of a bow shock, a comet…
Constraints on gamma-ray burst and supernova progenitors through circumstellar absorption lines
Allard-Jan van Marle, Norbert Langer, Guillermo Garcia-Segura
Long gamma-ray bursts are thought to be caused by a subset of exploding Wolf-Rayet stars. We argue that the circumstellar absorption lines in early supernova and in gamma-ray burst…
Type Ia supernovae from non-accreting progenitors
John Antoniadis, Savvas Chanlaridis, Götz Gräfener +1
Type Ia supernovae (SNe Ia) are manifestations of stars deficient of hydrogen and helium disrupting in a thermonuclear runaway. While explosions of carbon-oxygen white dwarfs are t…
The formation of low-mass helium white dwarfs orbiting pulsars: Evolution of low-mass X-ray binaries below the bifurcation period
Alina Istrate, Thomas Tauris, Norbert Langer
Millisecond pulsars (MSPs) are generally believed to be old neutron stars (NSs) which have been spun up to high rotation rates via accretion of matter from a companion star in a lo…
Boron depletion in Galactic early B-type stars reveals two different main sequence star populations
Harim Jin, Norbert Langer, Daniel J. Lennon +1
The evolution and fate of massive stars are thought to be affected by rotationally induced internal mixing. The surface boron abundance is a sensitive tracer of this in early B-typ…
A model of anisotropic winds from rotating stars for evolutionary calculations
Ben Hastings, Norbert Langer, Joachim Puls
Context: The surface properties of rotating stars can vary from pole to equator, resulting in anisotropic stellar winds which are not included in the currently available evolutiona…
The demographics of core-collapse supernovae. The role of binary evolution and CSM interaction
Andrea Ercolino, Harim Jin, Norbert Langer +3
The observational properties of core-collapse supernovae (CC-SNe) are shaped by the envelopes of their progenitors. In massive binary systems, mass-transfer alters the pre-SN struc…
Evolution towards and beyond accretion-induced collapse of massive white dwarfs and formation of millisecond pulsars
Thomas M. Tauris, Debashis Sanyal, Sung-Chul Yoon +1
Millisecond pulsars (MSPs) are generally believed to be old neutron stars (NSs), formed via type Ib/c core-collapse supernovae (SNe), which have been spun up to high rotation rates…
Rejuvenation of stellar mergers and the origin of magnetic fields in massive stars
Fabian R. N. Schneider, Philipp Podsiadlowski, Norbert Langer +2
Approximately 10% of massive OBA main-sequence (MS) and pre-MS stars harbour strong, large-scale magnetic fields. At the same time there is a dearth of magnetic stars in close bina…
The circumstellar medium around a rapidly rotating, chemically homogeneously evolving, possible gamma-ray burst progenitor
Allard Jan van Marle, Norbert Langer, Sung-Chul Yoon +1
Rapidly rotating, chemically homogeneously evolving massive stars are considered to be progenitors of long gamma-ray bursts. We present numerical simulations of the evolution of th…
Tides in asynchronous binary systems
Oswaldo Toledano, Edmundo Moreno, Gloria Koenigsberger +2
Stellar oscillations are excited in non-synchronously rotating stars in binary systems due to the tidal forces. Tangential components of the tides can drive a shear flow which beha…
SPIRITS: Uncovering Unusual Infrared Transients With Spitzer
Mansi M. Kasliwal, John Bally, Frank Masci +44
We present an ongoing, systematic search for extragalactic infrared transients, dubbed SPIRITS --- SPitzer InfraRed Intensive Transients Survey. In the first year, using Spitzer/IR…
Relating turbulent pressure and macroturbulence across the HR diagram with a possible link to γ-Dor stars
Luca Grassitelli, Luca Fossati, Norbert Langer +3
A significant fraction of the envelope of low- and intermediate-mass stars is unstable to convection, leading to sub-surface turbulent motion. Here, we consider and include the eff…
The period change of the Cepheid Polaris suggests enhanced mass loss
Hilding R. Neilson, Scott G. Engle, Ed Guinan +3
Polaris is one of the most observed stars in the night sky, with recorded observations spanning more than 200 years. From these observations, one can study the real-time evolution…
Stellar Evolution with Pulsation-Driven Mass Loss: The Case of LMC Cepheids
Hilding Neilson, Norbert Langer, Matteo Cantiello
The Cepheid mass discrepancy, the difference between mass estimates from stellar pulsation and stellar evolution models, is a long standing challenge for the understanding of stell…
Wolf-Rayet stars in the Small Magellanic Cloud as testbed for massive star evolution
Abel Schootemeijer, Norbert Langer
The majority of Wolf-Rayet (WR) stars represent the stripped cores of evolved massive stars who lost most of their hydrogen envelope. In low metallicity environments, such as the S…
Stellar mergers as the origin of the blue main-sequence band in young star clusters
Chen Wang, Norbert Langer, Abel Schootemeijer +10
Recent high-quality Hubble Space Telescope (HST) photometry shows that the main sequences (MS) stars of young star clusters form two discrete components in the color-magnitude diag…
The timescale of low-mass proto-helium white dwarf evolution
Alina Istrate, Thomas Tauris, Norbert Langer +1
A large number of low-mass (< 0.20 M_sun) helium white dwarfs (He WDs) have recently been discovered. The majority of these are orbiting another WD or a millisecond pulsar (MSP) in…
Interacting binaries on the Main Sequence as in-situ tracers of mass transfer efficiency and stability
Koushik Sen, Mathieu Renzo, Harim Jin +8
Understanding the transfer of mass and angular momentum in binary interactions is crucial for modelling the evolution of any interacting binary after the first mass transfer phase.…
Neutron star-companion interaction in core collapse supernovae. Population synthesis based on detailed binary evolution models
Andrea Ercolino, Norbert Langer, Avishay Gal-Yam +6
Most massive stars live in binary systems. When the first supernova (SN) in a binary occurs, the ejecta hit the companion, which may inflate as a consequence, and then interacts wi…
Binary-induced mass increase and helium enrichment of the envelopes of Type~IIP supernova progenitors
Caroline Mannes, Norbert Langer, Andrea Ercolino
Binary interactions are expected to play a major role in shaping the progenitor population of core-collapse supernovae, particularly in the era of deep, high-cadence transient surv…
Novel modelling of ultra-compact X-ray binary evolution - stable mass transfer from white dwarfs to neutron stars
Rahul Sengar, Thomas M. Tauris, Norbert Langer +1
Tight binaries of helium white dwarfs (He WDs) orbiting millisecond pulsars (MSPs) will eventually "merge" due to gravitational damping of the orbit. The outcome has been predicted…
Whispering in the dark: Faint X-ray emission from black holes with OB star companions
Koushik Sen, Ileyk El Mellah, Norbert Langer +3
Context. Recent astrometric and spectroscopic surveys of OB stars have revealed a few stellar-mass black holes (BHs) with orbital periods as low as 10 days. No X-ray counterpart ha…
Evolution of Gamma-Ray Burst Progenitors at Low Metallicity
Sung-Chul Yoon, Norbert Langer
Despite the growing evidence that long Gamma-Ray Bursts (GRBs) are associated with deaths of Wolf-Rayet stars, the evolutionary path of massive stars to GRBs and the exact nature o…
Properties of magnetars mimicking 56Ni-powered light curves in Type Ic superluminous supernovae
Takashi J. Moriya, Ting-Wan Chen, Norbert Langer
Many Type Ic superluminous supernovae have light-curve decline rates after their luminosity peak which are close to the nuclear decay rate of 56Co, consistent with the interpretati…
Rotating Massive Main-Sequence Stars I: Grids of Evolutionary Models and Isochrones
Ines Brott, Selma E. de Mink, Matteo Cantiello +6
We present a dense grid of evolutionary tracks and isochrones of rotating massive main-sequence stars. We provide three grids with different initial compositions tailored to compar…
Constraining the mass transfer in massive binaries through progenitor evolution models of Wolf-Rayet+O binaries
Jelena Petrovic, Norbert Langer, Karel A. van der hucht
Since close WR+O binaries are the result of a strong interaction of both stars in massive close binary systems, they can be used to constrain the highly uncertain mass and angular…
Diagnostic of the unstable envelopes of Wolf-Rayet stars
Luca Grassitelli, Andre-Nicolas Chene', Debashis Sanyal +4
The envelopes of stars near the Eddington limit are prone to various instabilities. A high Eddington factor in connection with the Fe opacity peak leads to convective instability,…
Binarity at LOw Metallicity (BLOeM): massive star variability revealed using a novel software tool for point-spread function fitting of TESS images
Pieterjan J. Van Daele, Dominic M. Bowman, Roey Ovadia +12
Massive stars, the progenitors of neutron stars and black holes, play a crucial role in shaping the chemical and radiative properties of entire galaxies through their winds and exp…
A new route towards merging massive black holes
Pablo Marchant, Norbert Langer, Philipp Podsiadlowski +2
Recent advances in gravitational-wave astronomy make the direct detection of gravitational waves from the merger of two stellar-mass compact objects a realistic prospect. Evolution…
Thermohaline mixing in evolved low-mass stars
Matteo Cantiello, Norbert Langer
Thermohaline mixing has recently been proposed to occur in low-mass red giants, with large consequence for the chemical yields of low-mass stars. We investigate the role of thermoh…
Observational consequences of turbulent pressure in the envelopes of massive stars
Luca Grassitelli, Luca Fossati, Sergio Simon-Diaz +3
The major mass fraction of the envelope of hot luminous stars is radiatively stable. However, the partial ionisation of hydrogen, helium and iron gives rise to extended sub-surface…
Chemical composition and origin of nebulae around Luminous Blue Variables
Henny J. G. L. M. Lamers, Antonella Nota, Nino Panagia +2
We use the analysis of the heavy element abundances (C, N, O, S) in circumstellar nebulae around Luminous Blue Variables to infer the evolutionary phase in which the material has b…
Formation of the Neutron Donor C13 in AGB Stars by Overshoot and Rotation
Falk Herwig, Norbert Langer
(abridged) Observations clearly show that low-mass AGB stars can provide a nucleosynthesis site of the s-process. Recent stellar evolution models indicate that radiative burning of…
Constraining mixing in massive stars in the Small Magellanic Cloud
Abel Schootemeijer, Norbert Langer, Nathan J. Grin +1
Context. The evolution of massive stars is strongly influenced by internal mixing processes such as semiconvection, convective core overshooting, and rotationally induced mixing. N…
Light-curve and spectral properties of ultra-stripped core-collapse supernovae leading to binary neutron stars
Takashi J. Moriya, Paolo A. Mazzali, Nozomu Tominaga +7
We investigate light-curve and spectral properties of ultra-stripped core-collapse supernovae. Ultra-stripped supernovae are the explosions of heavily stripped massive stars which…
Convective proton and He3 ingestion into helium burning: Nucleosynthesis during a post-AGB thermal pulse
Falk Herwig, Norbert Langer
A thermal pulse during the post-AGB phase of stellar evolution may lead to a unique mode of light element nucleosynthesis. The stage is set by the ingestion of the unprocessed enve…
3D MHD simulations of subsurface convection in OB stars
Matteo Cantiello, Jonathan Braithwaite, Axel Brandenburg +3
During their main sequence evolution, massive stars can develop convective regions very close to their surface. These regions are caused by an opacity peak associated with iron ion…
Mixing and the s-process in rotating AGB stars
Falk Herwig, Norbert Langer, Maria Lugaro
We model the nucleosynthesis during a radiative interpulse phase of a rotating 3Msun Asymptotic Giant Branch (AGB) star. We find an enhanced production of the neutron source specie…
A comprehensive grid of massive binary evolution models for the Galaxy - Surface properties of post-mass transfer stars
Harim Jin, Norbert Langer, Andrea Ercolino +1
Massive stars often evolve in binary systems, in which binary interactions significantly affect their evolution. Massive stars in the Galaxy serve as valuable testbeds for this due…
Stripped-envelope stars in different metallicity environments. II. Type I supernovae and compact remnants
David R. Aguilera-Dena, Bernhard Müller, John Antoniadis +4
Stripped-envelope stars can be observed as Wolf-Rayet (WR) stars, or as less luminous hydrogen-poor stars with low mass loss rates and transparent winds. Both types are potential p…
Inferring supernova IIb/Ib/Ic ejecta properties from light curves and spectra: Correlations from radiative-transfer models
Luc Dessart, D. John Hillier, Stan Woosley +4
We present 1-D non-Local-Thermodynamic-Equilibrium time-dependent radiative-transfer simulations for a large grid of supernovae (SNe) IIb/Ib/Ic that result from the terminal explos…
Explosion and nucleosynthesis of low redshift pair instability supernovae
Alexandra Kozyreva, Sung-Chul Yoon, Norbert Langer
Both recent observations and stellar evolution models suggest that pair-instability supernovae (PISNe) could occur in the local Universe, at metallicities below Z_Sun/3. Previous P…
Evidence for stellar mergers of evolved massive binaries: blue supergiants in the Large Magellanic Cloud
Athira Menon, Andrea Ercolino, Miguel A. Urbaneja +8
Blue supergiants are the brightest stars in their host galaxies and yet their evolutionary status has been a long-standing problem in stellar astrophysics. In this pioneering work,…
Interacting supernovae from wide massive binary systems
Andrea Ercolino, Harim Jin, Norbert Langer +1
Many supernovae (SNe) imply an interaction of the SN ejecta with matter (CSM) surrounding the progenitor star. This suggests that many massive stars may undergo various degrees of…
Thermonuclear and Electron-Capture Supernovae from Stripped-Envelope Stars
Savvas Chanlaridis, John Antoniadis, David R. Aguilera-Dena +3
(abridged) When stripped from their hydrogen-rich envelopes, stars with initial masses between 7 and 11 M develop massive degenerate cores and collapse. Depending on…
Mass-transferring binary stars as progenitors of interacting hydrogen-free supernovae
Andrea Ercolino, Harim Jin, Norbert Langer +1
Stripped-envelope supernovae (SNe) are H-poor transients produced at the end of the life of massive stars that previously lost their H-rich envelope. Their progenitors are thought…
Internal circulation in tidally locked massive binary stars -- Consequences for double black hole formation
Ben Hastings, Norbert Langer, Gloria Koenigsberger
Steady-state circulation currents are predicted in tidally deformed binary stars, which are believed to be progenitors of double black-hole merger events. This work aims to quantit…
Dust Production Factories in the Early Universe: Formation of Carbon Grains in Red-supergiant Winds of Very Massive Population III Stars
Takaya Nozawa, Sung-Chul Yoon, Keiichi Maeda +3
We investigate the formation of dust in a stellar wind during the red-supergiant (RSG) phase of a very massive Population III star with the zero-age main sequence mass of 500 M_sun…
Classical Cepheids Require Enhanced Mass Loss
Hilding R. Neilson, Norbert Langer, Scott G. Engle +2
Measurements of rates of period change of Classical Cepheids probe stellar physics and evolution. Additionally, better understanding of Cepheid structure and evolution provides gre…
The ages of young star clusters, massive blue stragglers and the upper mass limit of stars: analysing age dependent stellar mass functions
Fabian R. N. Schneider, Robert G. Izzard, Selma E. de Mink +7
Massive stars rapidly change their masses through strong stellar winds and mass transfer in binary systems. We show that such mass changes leave characteristic signatures in stella…
Evolution of rapidly rotating metal-poor massive stars towards gamma-ray bursts
Sung-Chul Yoon, Norbert Langer
Recent models of rotating massive stars including magnetic fields prove it difficult for the cores of single stars to retain enough angular momentum to produce a collapsar and gamm…
BlueMUSE: Project Overview and Science Cases
Johan Richard, Roland Bacon, Jérémy Blaizot +59
We present the concept of BlueMUSE, a blue-optimised, medium spectral resolution, panoramic integral field spectrograph based on the MUSE concept and proposed for the Very Large Te…
The occurrence of classical Cepheids in binary systems
Hilding R. Neilson, Fabian R. N. Schneider, Robert G. Izzard +2
Classical Cepheids, like binary stars, are laboratories for stellar evolution and Cepheids in binary systems are especially powerful ones. About one-third of Galactic Cepheids are…
Dynamics of H II regions around exiled O stars
Jonathan Mackey, Norbert Langer, Vasilii V. Gvaramadze
At least 25 per cent of massive stars are ejected from their parent cluster, becoming runaways or exiles, travelling with often-supersonic space velocities through the interstellar…
Clues on the Origin and Evolution of Massive Contact Binaries: Atmosphere Analysis of VFTS 352
Michael Abdul-Masih, Hugues Sana, Jon Sundqvist +10
The massive O4.5 V + O5.5 V binary VFTS 352 in the Tarantula nebula is one of the shortest-period and most massive overcontact binaries known. Recent theoretical studies indicate t…
Modeling contact binaries, III. Properties of a population of close, massive binaries
Matthias Fabry, Pablo Marchant, Norbert Langer +1
Among massive stars, binary interaction is the rule rather than the exception. The closest binaries, those with periods of less than about 10 days, undergo mass transfer during cor…
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…
The spin-up of contracting red supergiants
Alexander Heger, Norbert Langer
We report on a mechanism which may lead to a spin-up of the surface of a rotating single star leaving the Hayashi line, which is much stronger than the spin-up expected from the me…
Analytic approximations for massive close post-mass transfer binary systems
Christoph Schürmann, Norbert Langer, Joana A. Kramer +3
Massive binary evolution models are needed to predict massive star populations in star forming galaxies, the supernova diversity, and the number and properties of gravitational wav…
The Evolution of Surface Parameters of Rotating Massive Stars
Norbert Langer, Alexander Heger
We summarize the present status of the predictions of massive star models for the evolution of their surface properties. After discussing luminosity, temperature and chemical compo…