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Multi-D magnetohydrodynamic modelling of pulsar wind nebulae: recent progress and open questions

Published online by Cambridge University Press:  01 November 2016

B. Olmi*
Affiliation:
Dipartimento di Fisica ed Astronomia, Università degli Studi di Firenze, Via G. Sansone 1, 50019 Sesto F.no (Firenze), Italy INAF Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy INFN Sezione di Firenze, Via G. Sansone 1, 50019 Sesto F.no (Firenze), Italy
L. Del Zanna
Affiliation:
Dipartimento di Fisica ed Astronomia, Università degli Studi di Firenze, Via G. Sansone 1, 50019 Sesto F.no (Firenze), Italy INAF Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy INFN Sezione di Firenze, Via G. Sansone 1, 50019 Sesto F.no (Firenze), Italy
E. Amato
Affiliation:
Dipartimento di Fisica ed Astronomia, Università degli Studi di Firenze, Via G. Sansone 1, 50019 Sesto F.no (Firenze), Italy INAF Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy
N. Bucciantini
Affiliation:
Dipartimento di Fisica ed Astronomia, Università degli Studi di Firenze, Via G. Sansone 1, 50019 Sesto F.no (Firenze), Italy INAF Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy INFN Sezione di Firenze, Via G. Sansone 1, 50019 Sesto F.no (Firenze), Italy
A. Mignone
Affiliation:
Dipartimento di Fisica Generale ‘Amedeo Avogadro’ Università degli Studi di Torino, Via Pietro Giuria 1, 10125 Torino, Italy
*
Email address for correspondence: barbara.olmi@unifi.it

Abstract

In the last decade, the relativistic magnetohydrodynamic (MHD) modelling of pulsar wind nebulae, and of the Crab nebula in particular, has been highly successful, with many of the observed dynamical and emission properties reproduced down to the finest detail. Here, we critically discuss the results of some of the most recent studies: namely the investigation of the origin of the radio emitting particles and the quest for the acceleration sites of particles of different energies along the termination shock, by using wisp motions as a diagnostic tool; the study of the magnetic dissipation process in high magnetization nebulae by means of new long-term three-dimensional simulations of the pulsar wind nebula evolution; the investigation of the relativistic tearing instability in thinning current sheets, leading to fast reconnection events that might be at the origin of the Crab nebula gamma-ray flares.

Type
Research Article
Copyright
© Cambridge University Press 2016 

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