相关论文: The origin of peculiar jet-torus structure in the …
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…
In this letter, we describe results of new high-resolution axisymmetric relativistic MHD simulations of Pulsar Wind Nebulae. The simulations reveal strong breakdown of the equatorial symmetry and highly variable structure of the pulsar wind…
The recent Chandra image of the Crab nebula shows a striking, axisymmetric polar jet. It is shown that jets are formed in axisymmetric, magnetized pulsar winds and that the jet luminosity scales relative to the total as…
The formation of the toroidal and jet-like structures in the central part of the Crab Nebula is explained in the framework of Kennel & Coroniti theory. The only new element introduced by us in this theory is the initial anisotropy of the…
The structure and the evolution of Pulsar Wind Nebulae (PWNe) are studied by means of two-dimensional axisymmetric relativistic magnetohydrodynamic (RMHD) simulations. After the first imaging of the Crab Nebula with Chandra, a growing…
In the last few years, new observations by CHANDRA and XMM have shown that Pulsar Wind Nebulae present a complex but similar inner feature, with the presence of axisymmetric rings and jets, which is generally referred as {\it jet-torus…
Pulsar Wind Nebulae, and the Crab nebula in particular, are the best cosmic laboratories to investigate the dynamics of magnetized relativistic outflows and particle acceleration up to PeV energies. Multidimensional MHD modeling by means of…
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…
In this paper we give a detailed account of the first 3D relativistic magnetohydrodynamic (MHD) simulations of Pulsar Wind Nebulae (PWN), with parameters most suitable for the Crab Nebula. In order to clarify the new features specific to 3D…
Nearby pulsar wind nebulae exhibit complex morphological features: jets, torus, arcs and knots. These structures are well captured and understood in the scope of global magnetohydrodynamic models. However, the origin of knots in the inner…
In recent years, it has become a well-established paradigm that many aspects of the physics of Pulsar Wind Nebulae (PWNe) can be fully accounted for within a relativistic MHD description. Numerical simulations have proven extremely…
The Crab Nebula demonstrates that neutron stars can interact with their environments in spectacular fashion, their relativistic winds generating nebulae observable across the electromagnetic spectrum. At many previous conferences,…
I review the constraints placed on relativistic pulsar winds by comparing optical and X-ray images of the inner Crab Nebula on the one hand with two-dimensional MHD simulations on the other. The various proposals in the literature for…
In this review we describe recent observational and theoretical developments in our understanding of pulsar winds and pulsar-wind nebulae (PWNe). We put special emphasis on the results from observations of well-characterized PWNe of various…
We investigate the dynamical propagation of the South-East jet from the Crab pulsar interacting with supernova ejecta by means of three-dimensional relativistic MHD numerical simulations with the PLUTO code. The initial jet structure is set…
An axisymmetric model for the Crab Nebula is constructed to examine the flow dynamics in the nebula. The model is based on that of Kennel and Coroniti (1984), although we assume that the kinetic-energy-dominant wind is confined in an…
The nature of the supernova leading to the Crab Nebula has long been controversial because of the low energy that is present in the observed nebula. One possibility is that there is significant energy in extended fast material around the…
The Crab Nebula is one of the most efficient accelerators in the Galaxy and the only galactic source showing direct evidence of PeV particles. In spite of this, the physical process behind such effective acceleration is still a deep…
We investigate a class of pulsar wind nebulae that show synchrotron emission from a thick toroidal structure. The best studied such object is the small radio and X-ray nebula around the Vela pulsar, which can be interpreted as the result of…
The Crab Nebula is well-described at optical wavelengths and above by a steady-state magnetohydrodynamic model due to Kennel and Coroniti (1984). Can this class of model describe other pulsar-wind nebulae? I exhibit simple generalizations…