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How Massive Single Stars End Their Life
How massive stars die—what sort of explosion and remnant each produces—depends chiefly on the masses of their helium cores and hydrogen envelopes at death. For single stars, stellar winds are the
We present the spectrum of compact object masses: neutron stars and black holes (BHs) that originate from single stars in different environments. In particular, we calculate the dependence of maximum
The X-ray counterpart to the gravitational-wave event GW170817
The detection of X-ray emission at a location coincident with the kilonova transient provides the missing observational link between short γ-ray bursts and gravitational waves from neutron-star mergers, and gives independent confirmation of the collimated nature of the γ,ray-burst emission.
A New Look at the Binary Characteristics of Massive Stars
We constrain the properties of massive binaries by comparing radial velocity data on early-type stars in Cygnus OB2 with the expectations of Monte Carlo models. Our comparisons test several popular
Theoretical black hole mass distributions
We derive the theoretical distribution function of black hole masses by studying the formation processes of black holes. We use the results of recent two-dimensional simulations of stellar core
Formation Rates of Black Hole Accretion Disk Gamma-Ray Bursts
The cosmological origin of at least an appreciable fraction of classical gamma-ray bursts (GRBs) is now supported by redshift measurements for a half-dozen faint host galaxies. Still, the nature of
The effect of pair-instability mass loss on black-hole mergers
Context. Mergers of two stellar-origin black holes are a prime source of gravitational waves and are under intensive investigation. One crucial ingredient in their modeling has been neglected:
Swift and NuSTAR observations of GW170817: Detection of a blue kilonova
Ultraviolet and x-ray observations of a binary neutron star merger show a hot kilonova but no jet along the line of sight, which avoids both obscuration from the heaviest elements in the orbital plane and a direct view of any ultrarelativistic, highly collimated ejecta.
Rates and Delay Times of Type Ia Supernovae
We analyze the evolution of binary stars to calculate synthetic rates and delay times of the most promising Type Ia Supernovae (SNe Ia) progenitors. We present and discuss evolutionary scenarios in
A gravitational-wave standard siren measurement of the Hubble constant
A measurement of the Hubble constant is reported that combines the distance to the source inferred purely from the gravitational-wave signal with the recession velocity inferred from measurements of the redshift using the electromagnetic data.