Periodic radio morphology of gamma-ray binaries

TL;DR

This paper investigates the radio morphology of gamma-ray binaries using VLBI, revealing common properties and behaviors that inform understanding of their physical processes and system characteristics.

Contribution

It provides the first detailed analysis of the changing radio morphology of multiple gamma-ray binaries, establishing common features and behaviors on AU scales.

Findings

Discovered extended radio emission in PSR B1259-63 and HESS J0632+057.

Characterized the basic properties and behavior of radio emission in gamma-ray binaries.

Identified common morphological features across different gamma-ray binaries.

Abstract

Gamma-ray binaries allow us to study physical processes such as particle acceleration up to very-high energies and gamma-ray emission and absorption with changing geometrical configurations on a periodic basis. These sources produce outflows of radio-emitting particles whose structure can be imaged with Very Long Baseline Interferometry (VLBI). We have studied the changing morphology of the gamma-ray binaries LS I +61 303 and LS 5039, and we have discovered the extended emission of PSR B1259-63 and HESS J0632+057. Based on these results, we have established the basic properties and behaviour of the radio emission of gamma-ray binaries on AU scales, and we have contributed to find characteristics that are common to all of them. Here we present the most relevant properties of each source and the general properties of gamma-ray binaries, and we describe the implications on the nature of these binary systems.