On the time delay in binary systems

TL;DR

This paper investigates the impact of gravitomagnetic effects on electromagnetic signals in binary systems, focusing on how the angular momentum of a star influences pulse timing and frequency shifts, with implications for observational detection.

Contribution

It derives formulas for gravitomagnetic time delay effects in binary systems and assesses their observability in specific pulsar systems.

Findings

Gravitomagnetic effects influence pulse arrival times and spectra.

Current binary systems like PSR J0737-3039 are unsuitable for detecting these effects.

Theoretical formulas for time delay due to gravitomagnetism are established.

Abstract

The aim of this paper is to study the time delay on electromagnetic signals propagating across a binary stellar system. We focus on the antisymmetric gravitomagnetic contribution due to the angular momentum of one of the stars of the pair. Considering a pulsar as the source of the signals, the effect would be manifest both in the arrival times of the pulses and in the frequency shift of their Fourier spectra. We derive the appropriate formulas and we discuss the influence of different configurations on the observability of gravitomagnetic effects. We argue that the recently discovered PSR J0737-3039 binary system does not permit the detection of the effects because of the large size of the eclipsed region.