Measuring the orbital periods of low mass X-ray binaries in the X-ray band

TL;DR

This paper reviews methods for measuring the orbital periods of low mass X-ray binaries in the X-ray band, which are crucial for understanding their properties and the nature of their compact objects.

Contribution

It introduces various techniques for determining orbital periods in X-ray observations and reviews their application to different types of LMXBs.

Findings

Multiple methods for orbital period measurement are summarized.

Application of methods to eclipsing, dipping, and pulsar LMXBs is reviewed.

Fewer than half of LMXBs have known orbital periods.

Abstract

A low mass X-ray binary (LMXB) contains either a neutron star or a black hole accreting materials from its low mass companion star. It is one of the primary astrophysical sources for studying the stellar size compact objects and the accreting phenomena. As with other binary systems, the most important parameter of an LMXB is the orbital period, which allows us to learn about the nature of the binary system and constrain the properties of the system's components, including the compact object. As a result, measuring the orbital periods of LMXBs is essential for investigating these systems even though fewer than half of them have known orbital periods. This article introduces the different methods for measuring the orbital periods in the X-ray band and reviews their application to various types of LMXBs, such as eclipsing and dipping sources, as well as pulsar LMXBs.