Publications (29)
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…
Properties of OB star-black hole systems derived from detailed binary evolution models
N. Langer, C. Schürmann, K. Stoll +38
The recent gravitational wave measurements have demonstrated the existence of stellar mass black hole binaries. It is essential for our understanding of massive star evolution to i…
X-ray absorption spectroscopy study of the electronic and magnetic proximity effects in YBaCuO/LaCaMnO and LaSrCuO/LaCaMnO multilayers
M. A. Uribe-Laverde, S. Das, K. Sen +10
With x-ray absorption spectroscopy we investigated the orbital reconstruction and the induced ferromagnetic moment of the interfacial Cu atoms in YBaCuO/LaCa$…
X-ray emission from BH+O star binaries expected to descend from the observed galactic WR+O binaries
K. Sen, X. -T. Xu, N. Langer +3
In the Milky Way, 18 Wolf-Rayet+O (WR+O) binaries are known with estimates of their stellar and orbital parameters. Whereas black hole+O (BH+O) binaries are thought to evolve…
Structural, magnetic and superconducting properties of pulsed-laser-deposition-grown superlattices on -oriented substrates
S. Das, K. Sen, I. Marozau +9
Epitaxial La1.85Sr0.15CuO4/La2/3Ca1/3MnO3 superlattices on (001)-oriented LaSrAlO4 substrates have been grown with pulsed laser deposition technique. Their structural, magnetic and…
Electronic correlations in the van der Waals ferromagnet FeGeTe revealed by its charge dynamics
M. Corasaniti, R. Yang, K. Sen +5
The layered van der Waals ferromagnetic FeGeTe harbours an unconventional interplay between topology and magnetism, leading to a large anomalous Hall conductivity at low te…
Common origin for black holes in both high mass X-ray binaries and gravitational-wave sources
K. Belczynski, C. Done, S. Hagen +2
Black-hole (BH) high-mass X-ray binary (HMXB) systems are likely to be the progenitors of BH-BH mergers detected by LIGO/Virgo/KAGRA (LVK). Yet merging BHs reach higher masses ($\s…
Depth profile of the ferromagnetic order in a YBaCuO / LaCaMnO superlattice on a LSAT substrate: a polarized neutron reflectometry study
M. A. Uribe-Laverde, D. K. Satapathy, I. Marozau +10
Using polarized neutron reflectometry (PNR) we have investigated a YBa2Cu3O7(10nm)/La2/3Ca1/3MnO3(9nm)]10 (YBCO/LCMO) superlattice grown by pulsed laser deposition on a La0.3Sr0.7A…
Infrared ellipsometry study of the photo-generated charge carriers at the (001) and (110) surfaces of SrTiO crystals and the interface of corresponding LaAlO/SrTiO heterostructures
M. Yazdi-Rizi, P. Marsik, B. P. P. Mallett +7
With infrared (IR) ellipsometry and DC resistance measurements we investigated the photo-doping at the (001) and (110) surfaces of SrTiO (STO) single crystals and at the corres…
Synchrotron x-ray scattering study of charge-density-wave order in HgBaCuO
W. Tabis, B. Yu, I. Bialo +18
We present a detailed synchrotron x-ray scattering study of the charge-density-wave (CDW) order in simple tetragonal HgBaCuO (Hg1201). Resonant soft x-ray scattering m…
Binarity at LOw Metallicity (BLOeM): Enhanced multiplicity of early B-type dwarfs and giants at
J. I. Villaseñor, H. Sana, L. Mahy +32
Early B-type stars ( M) are frequently in multiple systems, as evidenced by spectroscopic campaigns in the Milky Way (MW) and the Large Magellanic Cloud (LMC). Pr…
X-ray absorption study of the ferromagnetic Cu moment at the interface and the variation of its exchange interaction with the Mn moment
K. Sen, E. Perret, A. Alberca +14
With x-ray absorption spectroscopy and polarized neutron reflectometry we studied how the magnetic proximity effect at the interface between the cuprate high- superconductor $…
Binarity at Low Metallicity (BLOeM) -- Multiplicity properties of Oe and Be stars
J. Bodensteiner, T. Shenar, H. Sana +40
Rapidly rotating classical OBe stars have been proposed as the products of binary interactions, and the fraction of Be stars with compact companions implies that at least some are.…
Raman scattering study of lattice and magnetic excitations in CrAs
K. Sen, Y. Yao, R. Heid +6
We report on the lattice and spin dynamics in the monopnictide CrAs using polarized Raman scattering. This system exhibits a first-order magneto-structural phase transition at T_N~…
Reverse Algols and hydrogen-rich Wolf-Rayet stars from very massive binaries
K. Sen, N. Langer, D. Pauli +6
Massive star feedback affects the evolution of galaxies, where the most massive stars may have the largest impact. The majority of massive stars are born as members of close binary…
A grid of fast-rotating, chemically-homogeneous, supernova and/or long-GRB progenitors
M. Renzo, O. Gottlieb, H. S. Chan +6
The understanding of the mechanism(s) by which massive stars collapse and possibly explode is rapidly maturing. Uncertainties in the structure of the stellar core at the onset of c…
Populations of evolved massive binary stars in the Small Magellanic Cloud I: Predictions from detailed evolution models
X. -T. Xu, C. Schürmann, N. Langer +13
Context. The majority of massive stars are born with a close binary companion. How this affects their evolution and fate is still largely uncertain, especially at low metallicity.…
Superconductivity and charge carrier localization in ultrathin bilayers
K. Sen, P. Marsik, S. Das +6
/ (LSCO15/LCO) bilayers with a precisely controlled thickness of N unit cells (UCs) of the former and M UCs of the latter ([LS…
Anomalous lattice anharmonicity and spin-lattice coupling in spin orbit coupled halide K2IrBr6
S. Bhatia, A. Ahmad, M. Zeeshan +5
The interplay between lattice distortions, magnetism, and spin-orbit coupling in 5d transition-metal halides offers a fertile platform for exploring correlated spin-lattice dynamic…
Multiplicity of Massive Stars at Low Metallicity: Early Results from the BLOeM Campaign
T. Shenar, J. Bodensteiner, M. Abdul-Masih +73
The BLOeM campaign presents the first large‑scale spectroscopic survey of 929 massive stars in the Small Magellanic Cloud, revealing a high intrinsic binary fraction (>70%) among m…
Binarity at LOw Metallicity (BLOeM): Multiplicity of early B-type supergiants in the Small Magellanic Cloud
N. Britavskiy, L. Mahy, D. J. Lennon +32
The blue supergiant (BSG) domain contains a large variety of stars whose past and future evolutionary paths are still highly uncertain. Since binary interaction plays a crucial rol…
Atmospheric NLTE models for the spectroscopic analysis of blue stars with winds. V. Complete comoving frame transfer, and updated modeling of X-ray emission
J. Puls, F. Najarro, J. O. Sundqvist +1
Context. Obtaining precise stellar and wind properties and abundance patterns of massive stars is crucial to understanding their nature and interactions with their environments, as…
Absence of temperature-dependent phonon anomalies in Sr2IrO4 and Sr3Ir2O7
K. Sen, R. Heid, S. M. Souliou +8
Following previous works reporting an anomalous behavior of several zone-center optical phonons across the magnetic transition of square lattice iridates Sr2IrO4 and Sr3Ir2O7, we h…
Searching for compact objects in the single-lined spectroscopic binaries of the young Galactic cluster NGC 6231
G. Banyard, L. Mahy, H. Sana +7
Recent evolutionary computations predict that a few percent of massive OB stars in binary systems should have a dormant BH companion. Despite several reported X-ray quiet OB+BH sys…
Detailed models of interacting short-period massive binary stars
K. Sen, N. Langer, P. Marchant +10
About a quarter of massive binary stars undergo mass transfer while both stars burn hydrogen at their cores, first on the thermal and then on the nuclear timescale. The nuclear tim…
Binarity at LOw Metallicity (BLOeM): The multiplicity properties and evolution of BAF-type supergiants
L. R. Patrick, D. J. Lennon, F. Najarro +36
Given the uncertain evolutionary status of blue supergiant stars, their multiplicity properties hold vital clues to better understand their origin and evolution. As part of The Bin…
Bulk-like structural, magnetic and optical properties of (111)- and (001)-NiO thin films
S. Kaur, Smriti Bhatia, Pooja +4
We have grown (111)- and (001)-oriented NiO thin films on (0001)-Sapphire and (001)-MgO substrates using pulsed laser deposition (PLD), respectively. DC magnetic susceptibility mea…
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…
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…