A high-mass X-ray binary descended from an ultra-stripped supernova

TL;DR

This paper demonstrates that a specific high-mass X-ray binary originated from an ultra-stripped supernova, providing insights into the evolutionary pathways leading to binary neutron star systems and their role in heavy element production.

Contribution

It presents evidence linking a known high-mass X-ray binary to an ultra-stripped supernova origin, elucidating the formation process of binary neutron star systems.

Findings

The binary's orbital elements match those of known Be X-ray binaries.

The neutron star in the system formed via an ultra-stripped supernova.

This supports the evolutionary link between ultra-stripped supernovae and binary neutron star formation.

Abstract

Ultra-stripped supernovae are different from other terminal explosions of massive stars, as they show little or no ejecta from the actual supernova event. They are thought to occur in massive binary systems after the exploding star has lost its surface through interactions with its companion. Such supernovae produce little to no kick, leading to the formation of a neutron star without loss of the binary companion, which itself may also evolve into another neutron star. Here we show that a recently discovered high-mass X-ray binary, CPD -29 2176 (CD -29 5159; SGR 0755-2933), has an evolutionary history that shows the neutron star component formed during an ultra-stripped supernova. The binary has orbital elements that are similar both in period and in eccentricity to one of 14 Be X-Ray binaries that have both known orbital periods and eccentricities. The identification of the progenitors systems for ultra-stripped supernovae is necessary as their evolution pathways leads to the formation of a binary neutron star systems. Binary neutron stars, such as the system that produced the kilonova GW170817 that was observed with both electromagnetic and gravitational energy, are known to produce a large quantity of heavy elements.