Modeling statistical properties of the X‐ray emission from aged pulsar wind nebulae. (March 2014)

• Record Type: Journal Article
• Authors: Bandiera, R.
• Is Part Of: Astronomische Nachrichten. Volume 335:issue 3(2014)
• Page Start: 307
• Page End: 312
• Publication Date: 2014-03
• Subjects: Astronomy -- Periodicals; 520.5
• DOI: 10.1002/asna.201312037
• Languages: English
• ISSNs: 0004-6337

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The number of known pulsar wind nebulae (PWNe) has recently increased considerably, and the majority of them are now middle‐age objects. Recent studies have shown a clear correlation of both X‐ray luminosity and size with the PWN age, but fail in providing a thorough explanation of the observed trends. Here I propose a different approach to these effects, based on the hypothesis that the observed trends do not simply reproduce the evolution of a "typical" PWN, but are a combined effect of PWNe evolving under different ambient conditions, the leading parameter being the ambient medium density. Using a simple analytic approach, I show that most middle‐aged PWNe are more likely observable during the reverberation phase, and I succeed in reproducing trends consistent with those observed, provided that the evolution of the X‐ray emitting electrons remains adiabatic over the whole reverberation phase. As a direct consequence, I show that the X‐ray spectra of older PWNe should be harder, also consistent with observations. (© 2014 WILEY‐VCH Verlag GmbH &amp; Co. KGaA, Weinheim)</p> </abstract>