Theory of Pulsar Wind Nebulae

TL;DR

Recent high-resolution observations and advanced modeling have significantly enhanced our understanding of Pulsar Wind Nebulae, revealing complex structures and emission properties that inform theories of pulsar wind interactions and particle acceleration.

Contribution

This paper reviews the standard theory and recent advances in modeling the evolution and emission of PWNe, demonstrating improved agreement with observations.

Findings

Models now accurately reproduce X-ray emissions.

Discovery of complex inner features like rings and jets.

Enhanced understanding of pulsar wind interactions.

Abstract

Our understanding of Pulsar Wind Nebulae (PWNe), has greatly improved in the last years thanks to unprecedented high resolution images taken from the HUBBLE, CHANDRA and XMM satellites. The discovery of complex but similar inner features, with the presence of unexpected axisymmetric rings and jets, has prompted a new investigation into the dynamics of the interaction of the pulsar winds with the surrounding SNR, which, thanks to the improvement in the computational resources, has let to a better understanding of the properties of these objects. On the other hand the discovery of non-thermal emission from bow shock PWNe, and of systems with a complex interaction between pulsar and SNR, has led to the development of more reliable evolutionary models. I will review the standard theory of PWNe, their evolution, and the current status in the modeling of their emission properties, in particular I will show that our evolutionary models are able to describe the observations, and that the X-ray emission can now be reproduced with sufficient accuracy, to the point that we can use these nebulae to investigate fundamental issues as the properties of relativistic outflows and particle acceleration.