Searching for compact objects in the single-lined spectroscopic binaries of the young Galactic cluster NGC 6231

Abstract

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 systems over the last couple of years, finding them with certainty remains challenging. These have great importance as they can be gravitational wave (GW) source progenitors, and are landmark systems in constraining supernova kick physics. This work aims to characterise the hidden companions to the single-lined spectroscopic binaries (SB1s) in the B star population of the young open Galactic cluster NGC 6231 to find candidate systems for harbouring compact object companions. With the orbital solutions for each SB1 previously constrained, we applied Fourier spectral disentangling to multi-epoch optical VLT/FLAMES spectra of each target to extract a potential signature of a faint companion, and to identify newly disentangled double-lined spectroscopic binaries (SB2s). For targets where the disentangling does not reveal any signature of a stellar companion, we performed atmospheric and evolutionary modelling on the primary to obtain constraints on the unseen companion. Seven newly classified SB2 systems with mass ratios down to near 0.1 were identified. From the remaining targets, for which no faint companion could be extracted from the spectra, four are found to have companion masses in the predicted mass ranges of neutron stars (NSes) and BHes. Two of these have companion masses between 1 and 3.5 $M_{\odot }$, making them potential hosts of NSes (or lower mass main sequence stars). The other two are between 2.5 to 8 $M_{\odot }$ and 1.6 and 26 $M_{\odot }$, respectively, and so are identified as candidates for harbouring BH companions. However, unambiguous identification of these systems as X-ray quiet compact object harbouring binaries requires follow up observations.

arXiv commentSubmitted to A&A

References in corpus (86)

• On the variation of the Initial Mass Function
• Modules for Experiments in Stellar Astrophysics (MESA)
• Binary interaction dominates the evolution of massive stars
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• Estimating distances from parallaxes. V: Geometric and photogeometric distances to 1.47 billion stars in Gaia Early Data Release 3
• Galaxies on FIRE (Feedback In Realistic Environments): Stellar Feedback Explains Cosmologically Inefficient Star Formation
• The first gravitational-wave source from the isolated evolution of two 40-100 Msun stars
• Rotating Massive Main-Sequence Stars I: Grids of Evolutionary Models and Isochrones
• A Grid of NLTE Line-Blanketed Model Atmospheres of O-type Stars
• A Grid of NLTE Line-Blanketed Model Atmospheres of Early B-type Stars
• On The Maximum Mass of Stellar Black Holes
• A new route towards merging massive black holes
• Southern Massive Stars at High Angular Resolution: Observational Campaign and Companion Detection
• Second ROSAT all-sky survey (2RXS) source catalogue
• Type Ib/c supernovae in binary systems I. Evolution and properties of the progenitor stars
• Secular evolution of compact binaries near massive black holes: gravitational wave sources and other exotica
• BlackCAT: A catalogue of stellar-mass black holes in X-ray transients
• The chemically homogeneous evolutionary channel for binary black hole mergers: rates and properties of gravitational-wave events detectable by advanced LIGO
• Formation and Evolution of Compact Object Binaries in AGN Disks
• Kinematics in Young Star Clusters and Associations with Gaia DR2
• The Mass of the Black Hole in Cygnus X-1
• Black Holes: The Next Generation -- Repeated Mergers in Dense Star Clusters and their Gravitational-Wave Properties
• Binary black hole mergers from field triples: properties, rates and the impact of stellar evolution
• The effect of the metallicity-specific star formation history on double compact object mergers
• Possible Indirect Confirmation of the Existence of Pop III Massive Stars by Gravitational Wave
• Cygnus X-1 contains a 21-solar mass black hole -- implications for massive star winds
• Rotational mixing in massive binaries: detached short-period systems
• The origin of spin in binary black holes: Predicting the distributions of the main observables of Advanced LIGO
• The spin of the second-born black hole in coalescing binary black holes
• Forming short-period Wolf-Rayet X-ray binaries and double black holes through stable mass transfer
• A Be-type star with a black hole companion
• A wide star-black-hole binary system from radial-velocity measurements
• Spectral models for binary products: Unifying Subdwarfs and Wolf-Rayet stars as a sequence of stripped-envelope stars
• BONNSAI: a Bayesian tool for comparing stars with stellar evolution models
• The role of mass transfer and common envelope evolution in the formation of merging binary black holes
• POLLUX : a database of synthetic stellar spectra
• An XMM-Newton view of the young open cluster NGC 6231 -- II. The OB star population
• The Tarantula Massive Binary Monitoring: I. Observational campaign and OB-type spectroscopic binaries
• Pre-supernova evolution, compact object masses and explosion properties of stripped binary stars
• The evolution of stellar triples: The most common evolutionary pathways
• The 'hidden' companion in LB-1 unveiled by spectral disentangling
• The massive star binary fraction in young open clusters I. NGC 6231 revisited
• Cosmic Rates of Black Hole Mergers and Pair-Instability Supernovae from Chemically Homogeneous Binary Evolution
• Formation pathway of Population III coalescing binary black holes through stable mass transfer
• Properties of OB star-black hole systems derived from detailed binary evolution models
• Is HR 6819 a triple system containing a black hole? -- An alternative explanation
• The massive star binary fraction in young open clusters - II. NGC 6611 (Eagle Nebula)
• Grid Search in Stellar Parameters: a software for spectrum analysis of single stars and binary systems
• The masses, and the mass discrepancy of O-type stars
• The mass discrepancy in intermediate- and high-mass eclipsing binaries: the need for higher convective core masses
• A naked-eye triple system with a nonaccreting black hole in the inner binary
• Hypercritical Accretion, Induced Gravitational Collapse, and Binary-Driven Hypernovae
• An X-ray quiet black hole born with a negligible kick in a massive binary within the Large Magellanic Cloud
• Detailed models of interacting short-period massive binary stars
• Identifying quiescent compact objects in massive Galactic single-lined spectroscopic binaries
• First Stellar Binary Black Holes: Strongest Gravitational Wave Burst Sources
• The Birth Function for Black Holes and Neutron Stars in Close Binaries
• The VLT-FLAMES Tarantula Survey XVIII. Classifications and radial velocities of the B-type stars
• No signature of the orbital motion of a putative 70 solar mass black hole in LB-1
• Chemically Homogeneous Evolution: A rapid population synthesis approach
• The massive star binary fraction in young open clusters - III. IC 2944 and the Cen OB2 association
• Early-type stars in the young open cluster NGC 2244 and in the Mon OB2 association I. The multiplicity of O-type stars
• The Tarantula Massive Binary Monitoring VI: Characterisation of hidden companions in 51 single-lined O-type binaries, a flat mass-ratio distribution, and black-hole binary candidates
• The presupernova core mass-radius relation of massive stars: understanding its formation and evolution
• A black hole detected in the young massive LMC cluster NGC 1850
• The young massive SMC cluster NGC 330 seen by MUSE II. Multiplicity properties of the massive-star population
• Population Synthesis of Black Hole Binaries with Normal-Star Companions: I. Detached Systems
• The Tarantula Massive Binary Monitoring. IV. Double-lined photometric binaries
• A spectroscopic investigation of the O-type star population in four Cygnus OB associations. I. Determination of the binary fraction
• Clues on the Origin and Evolution of Massive Contact Binaries: Atmosphere Analysis of VFTS 352
• The Initial Mass Function and the Surface Density Profile of NGC 6231
• Prospects of Finding Detached Black Hole-Star Binaries with TESS
• An XMM-Newton view of the young open cluster NGC 6231 III. Optically faint X-ray sources
• A Fresh Catch of Massive Binaries in the Cygnus OB2 Association
• Constraining the Overcontact Phase in Massive Binary Evolution I. Mixing in V382 Cyg, VFTS 352, and OGLE SMC-SC10 108086
• HR 6819 is a binary system with no black hole -- revisiting the source with infrared interferometry and optical integral field spectroscopy
• BONNSAI: correlated stellar observables in Bayesian methods
• Stellar-Mass Black Holes in the Solar Neighborhood
• Optical Analysis and Modeling of HD96670, a new Black Hole X-ray Binary Candidate
• A Chandra X-ray study of the young star cluster NGC 6231: low-mass population and initial mass function
• MONOS.II. Orbit review and analysis for 35 single-lined spectroscopic binary systems and candidates
• Confirming NGC 6231 as the parent cluster of the runaway high-mass X-ray binary HD 153919/4U 1700-37 with Gaia DR2
• A Survey for High-Mass Eclipsing Binaries
• The H-alpha Emission Line Variations of HR 6819
• Resolving the dynamical mass tension of the massive binary 9 Sagittarii
• Pulsating stars in NGC 6231 Frequency analysis and photometric mode identification near the main sequence

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