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Related papers: The "sigma" problem of the Crab pulsar wind

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A solution to the sigma problem - that of finding a mechanism capable of converting Poynting energy flux to particle-borne energy flux in a pulsar wind - was proposed several years ago by Coroniti and Michel who considered a particular…

Astrophysics · Physics 2007-05-23 J. G. Kirk , O. Skjaeraasen , Y. A. Gallant

Flows in which energy is transported predominantly as Poynting flux are thought to occur in pulsars, gamma-ray bursts and relativistic jets from compact objects. The fluctuating component of the magnetic field in such a flow can in…

Astrophysics · Physics 2009-11-07 J. G. Kirk , O. Skjaeraasen

It is generally thought that most of the spin-down power of a pulsar is carried away in an MHD wind dominated by Poynting flux. In the case of an oblique rotator, a significant part of this energy can be considered to be in a low-frequency…

Astrophysics · Physics 2009-10-31 Y. Lyubarsky , J. G. Kirk

Pulsars and central engines of long gamma ray burst -- collapsars -- may produce highly magnetized (Poynting flux dominated) outflows expanding in a dense surrounding (interstellar medium or stellar material). For certain injection…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Maxim Lyutikov

Two-dimensional, relativistic, MHD simulations of pulsar-wind powered nebulae provide strong constraints on the properties of the winds themselves. In particular, they confirm that Poynting flux must be converted into particle energy close…

Astrophysics · Physics 2007-05-23 J. G. Kirk

A pulsar wind is a relativistic outflow dominated by Poynting energy at its base. Based on the standard ideal magnetohydrodynamic (MHD) model of pulsar wind nebulae (PWNe) with the ordered magnetic field, the observed slow expansion $v_{\rm…

High Energy Astrophysical Phenomena · Physics 2018-06-06 Shuta J. Tanaka , Kenji Toma , Nozomu Tominaga

The spin-down power of a pulsar is thought to be carried away in an MHD wind in which, at least close to the star, the energy transport is dominated by Poynting flux. The pulsar drives a low-frequency wave in this wind, consisting of…

Astrophysics · Physics 2009-11-07 J. G. Kirk , Y. Lyubarsky

The termination shock of a pulsar wind is located roughly where the ram pressure matches that of the surrounding medium. Downstream of the shock, MHD models of the diffuse nebular emission suggest the plasma is weakly magnetized. However,…

High Energy Astrophysical Phenomena · Physics 2013-03-28 Iwona Mochol , John G. Kirk

In this paper, we present an expanding disc model to derive polarization properties of the Crab nebula. The distribution function of the plasma and the energy density of the magnetic field are prescribed as function of the distance from the…

Astrophysics · Physics 2009-11-13 Yuji Nakamura , Shinpei Shibata

In this letter we report on turbulent acceleration of the dissipation of magnetic field in the postshock re- gion of a Poynting flux-dominated flow, such as the Crab pulsar wind nebula. We have performed two- dimensional resistive…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Makoto Takamoto , Tsuyoshi Inoue , Shu-ichiro Inutsuka

Using the exact solution of the axisymmetric pulsar magnetosphere derived in a previous publication and the conservation laws of the associated MHD flow, we show that the Lorentz factor of the outflowing plasma increases linearly with…

Astrophysics · Physics 2016-08-30 Ioannis Contopoulos , Demosthenes Kazanas

Successful phenomenological models of pulsar wind nebulae assume efficient dissipation of the Poynting flux of the magnetized electron-positron wind as well as efficient acceleration of the pairs in the vicinity of the termination shock,…

High Energy Astrophysical Phenomena · Physics 2016-08-03 M. Lemoine

We interpret $\gamma$-ray flares from the Crab Nebula as the signature of turbulence in the pulsar's electromagnetic outflow. Turbulence is triggered upstream by dynamical instability of the wind's oscillating magnetic field, and…

High Energy Astrophysical Phenomena · Physics 2016-06-01 Jonathan Zrake

By means of two- and three-dimensional particle-in-cell simulations, we investigate the process of driven magnetic reconnection at the termination shock of relativistic striped flows. In pulsar winds and in magnetar-powered relativistic…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Lorenzo Sironi , Anatoly Spitkovsky

Magnetic dissipation is frequently invoked as a way of powering the observed emission of relativistic flows in Gamma Ray Bursts and Active Galactic Nuclei. Pulsar Wind Nebulae provide closer to home cosmic laboratories which can be used to…

High Energy Astrophysical Phenomena · Physics 2015-06-05 S. S. Komissarov

This paper deals with the Crab Nebula problem to suggest that particle acceleration takes place not only at the inner shock but also over a larger region in the nebula with disordered magnetic field. Kennel and Cornoniti (1984) constructed…

Astrophysics · Physics 2007-05-23 S. Shibata , M. Tomatsuri , M. Shimanuki , K. Saito , Y. Nakamura , K. Mori

The recently discovered gamma-ray flares from the Crab nebula are generally attributed to the magnetic energy release in a highly magnetized region within the nebula. I argue that such a region naturally arises in the polar region of the…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Y. E. Lyubarsky

We interpret the observed X-ray morphology of the central part of the Crab Nebula (torus + jets) in terms of the standard theory by Kennel and Coroniti (1984). The only new element is the inclusion of anisotropy in the energy flux from the…

Astrophysics · Physics 2009-11-07 S. V. Bogovalov , D. V. Khangoulyan

The pulsar wind model is updated by considering the effect of particle density and pulsar death. It can describe both the short term and long term rotational evolution of pulsars consistently. It is applied to model the rotational evolution…

High Energy Astrophysical Phenomena · Physics 2015-06-23 F. F. Kou , H. Tong

We can probe observationally and reproduce theoretically intricate properties of the Crab Nebula nearest to the pulsar - The Inner Knot. The tiny knot is indeed a bright spot on the surface of a quasi-stationary magnetic relativistic shock…

High Energy Astrophysical Phenomena · Physics 2017-02-01 Maxim Lyutikov
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