Core-Collapse Supernovae in Binaries as the Origin of Galactic Hyper-Runaway Stars

Abstract

Several stars detected moving at velocities near to or exceeding the Galactic escape speed likely originated in the Milky Way disc. We quantitatively explore the `binary supernova scenario' hypothesis, wherein these `hyper-runaway' stars are ejected at large peculiar velocities when their close, massive binary companions undergo a core-collapse supernova and the binary is disrupted. We perform an extensive suite of binary population synthesis simulations evolving massive systems to determine the assumptions and parameters which most impact the ejection rate of fast stars. In a simulation tailored to eject fast stars, we find the most likely hyper-runaway star progenitor binary is composed of a massive ($\sim$$30{\mathrm{M}}_{\odot }$) primary and a $\sim$$3-4{\mathrm{M}}_{\odot }$ companion on an orbital period that shrinks to $\lesssim$1 day prior to the core collapse following a common envelope phase. The black hole remnant formed from the primary must receive a natal kick $\gtrsim$1000 $\mathrm{km}{\mathrm{s}}^{-1}$ to disrupt the binary and eject the companion at a large velocity. We compare the fast stars produced in these simulations to a contemporary census of early-type Milky Way hyper-runaway star candidates. We find that these rare objects may be produced in sufficient number only when poorly-constrained binary evolution parameters related to the strength of post-core collapse remnant natal kicks and common envelope efficiency are adjusted to values currently unsupported -- but not excluded -- by the literature. We discuss observational implications that may constrain the existence of these putative progenitor systems.

Accepted for publication in MNRAS following minor revisions. 22 pages, 6 figures, 4 tables

References in corpus (42)

• Binary interaction dominates the evolution of massive stars
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• galpy: A Python Library for Galactic Dynamics
• The Evolution of Compact Binary Star Systems
• Post-common-envelope binaries from SDSS. IX: Constraining the common-envelope efficiency
• Toward Complete Statistics of Massive Binary Stars: Penultimate Results from the Cygnus OB2 Radial Velocity Survey
• Rings and Radial Waves in the Disk of the Milky Way
• Investigating stellar-mass black hole kicks
• A cosmic abundance standard: chemical homogeneity of the solar neighbourhood and the ISM dust-phase composition
• Interaction of massive black hole binaries with their stellar environment: I. Ejection of hypervelocity stars
• The observed velocity distribution of young pulsars
• Reconstructing the star formation history of the Milky Way disc(s) from chemical abundances
• The Explosion of Helium Stars Evolved With Mass Loss
• Efficiency of mass transfer in massive close binaries, Tests from double-lined eclipsing binaries in the SMC
• Neutron star kicks by the gravitational tug-boat mechanism in asymmetric supernova explosions: progenitor and explosion dependence
• The fastest unbound star in our Galaxy ejected by a thermonuclear supernova
• Simple recipes for compact remnant masses and natal kicks
• Black hole formation and fallback during the supernova explosion of a $40{\mathrm{M}}_{\odot }$ star
• Evolution of Mass Functions of Coeval Stars through Wind Mass Loss and Binary Interactions
• Hypervelocity Stars: From the Galactic Center to the Halo
• An Alternative Origin for Hypervelocity Stars
• On type Ia supernovae and the formation of single low-mass white dwarfs
• The Galactic distribution of X-ray binaries and its implications for compact object formation and natal kicks
• A Successful Targeted Search for Hypervelocity Stars
• Maximum speed of hypervelocity stars ejected from binaries
• Comparing Neutron Star Kicks to Supernova Remnant Asymmetries
• Binary dynamics near a massive black hole
• Magnetic Field Amplification During the Common Envelope Phase
• Kinematics of hypervelocity stars in the triaxial halo of the Milky Way
• Runaway and walkaway stars from the ONC with Gaia DR2
• Predicted Space Motions for Hypervelocity and Runaway Stars: Proper Motions and Radial Velocities for the GAIA Era
• LMC origin of the hyper-velocity star HE 0437-5439. Beyond the supermassive black hole paradigm
• Proper Motions and Trajectories for 16 Extreme Runaway and Hypervelocity Stars
• Discovery of two new hypervelocity stars from the LAMOST spectroscopic surveys
• Joint constraints on the Galactic dark matter halo and Galactic Centre from hypervelocity stars
• Hypervelocity Stars from the Andromeda Galaxy
• The Nearest High-Velocity Stars Revealed by LAMOST Data Release 1
• Dynamical evolution of star-forming regions: III. Unbound stars and predictions for Gaia
• On the Common Envelope Efficiency
• HD271791: dynamical versus binary-supernova ejection scenario
• A new look at distances and velocities of neutron stars
• Hypervelocity Stars: Young and Heavy or Old and Light?

Cited by in corpus (7)

• Towards a Realistic Explosion Landscape for Binary Population Synthesis
• Gaia EDR3 in 6D: Searching for unbound stars in the Galaxy
• Mysterious Odd Radio Circle near the Large Magellanic Cloud -- An Intergalactic Supernova Remnant?
• Comparing hypervelocity star populations from the Large Magellanic Cloud and the Milky Way
• Blue extreme disk-runaway stars with Gaia EDR3
• Predicted spatial and velocity distributions of ejected companion stars of helium accretion-induced thermonuclear supernovae
• Constraints on the abundance of $0.01c$ stellar engines in the Milky Way