From young to old: the evolutionary path of Pulsar Wind Nebulae

TL;DR

This paper reviews the evolutionary stages of Pulsar Wind Nebulae, highlighting recent modeling advances, observational insights, and open questions about their physical properties across different ages.

Contribution

It provides a comprehensive overview of the evolution, modeling approaches, and recent progress in understanding Pulsar Wind Nebulae's diverse properties.

Findings

Different morphological features at various ages are explained by evolutionary models.

Recent numerical simulations have improved understanding of PWN physics.

Open questions remain about the detailed physics governing PWN evolution.

Abstract

Pulsar wind nebulae are fascinating systems, and archetypal sources for high-energy astrophysics in general. Due to their vicinity, brightness, to the fact that they shine at multi-wavelengths, and especially to their long-living emission at gamma-rays, modelling their properties is particularly important for the correct interpretation of the visible Galaxy. A complication in this respect is the variety of properties and morphologies they show at different ages. Here we discuss the differences among the evolutionary phases of pulsar wind nebulae, how they have been modeled in the past and what progresses have been recently made. We approach the discussion from a phenomenological, theoretical (especially numerical) and observational point of view, with particular attention to the most recent results and open questions about the physics of such intriguing sources.