A Dynamical Model for the Evolution of a Pulsar Wind Nebula inside a Non-Radiative Supernova Remnant

TL;DR

This paper introduces a semi-analytic dynamical and radiative model for pulsar wind nebulae within supernova remnants, explaining their evolution and spectral features, with implications for cosmic ray observations.

Contribution

The paper presents a novel coupled dynamical and radiative model that traces pulsar wind nebula evolution throughout the supernova remnant's lifetime, predicting observable spectral features.

Findings

Model reproduces features of known pulsar wind nebulae

Predicts spectral signatures detectable with new radio and gamma-ray facilities

Implications for cosmic ray positron and lepton measurements

Abstract

A pulsar wind nebula inside a supernova remnant provides a unique insight into the properties of the central neutron star, the relativistic wind powered by its loss of rotational energy, its progenitor supernova, and the surrounding environment. In this paper, we present a new semi-analytic model for the evolution of such a pulsar wind nebula which couples the dynamical and radiative evolution of the pulsar wind nebulae, traces the evolution of the pulsar wind nebulae throughout the lifetime of the supernova remnant produced by the progenitor explosion, and predicts both the dynamical and radiative properties of the pulsar wind nebula during this period. We also discuss the expected evolution for a particular set of these parameters, and show it reproduces many puzzling features of known young and old pulsar wind nebulae. The model also predicts spectral features during different phases of its evolution detectable with new radio and gamma-ray observing facilities. Finally, this model has implications for determining if pulsar wind nebulae can explain the recent measurements of the cosmic ray positron fraction by PAMELA and the cosmic ray lepton spectrum by ATIC and HESS.