A search for radio pulsations from neutron star companions of four subdwarf B stars

TL;DR

This study conducted radio searches for neutron star companions to four subdwarf B stars but found no pulsations, providing constraints on the presence of neutron stars in these systems.

Contribution

First radio pulsation search targeting neutron star companions of subdwarf B stars, offering new observational constraints.

Findings

No pulsed radio emission detected from the four systems.

Set flux density upper limits as low as 0.2 mJy.

Implications for the nature of the companions and subdwarf B star formation.

Abstract

We searched for radio pulsations from the potential neutron star binary companions to subdwarf B stars HE 0532-4503, HE 0929-0424, TON S 183 and PG 1232-136. Optical spectroscopy of these subdwarfs has indicated they orbit a companion in the neutron star mass range. These companions are thought to play an important role in the poorly understood formation of subdwarf B stars. Using the Green Bank Telescope we searched down to mean flux densities as low as 0.2 mJy, but no pulsed emission was found. We discuss the implications for each system.