Related papers: A corrugated termination shock in pulsar wind nebu…
Collisionless fast-magnetosonic shocks are often treated as smooth, planar boundaries, yet observations point to organized corrugation of the shock surface. A plausible driver is upstream turbulence. Broadband fluctuations arriving at the…
The dynamics of relativistic magnetized mass loaded outflows carrying toroidal magnetic field is analyzed in the context of Pulsar Wind Nebulae (PWNs). Mass loading is very efficient in slowing down super-relativistic magnetized flows and…
We investigate the acceleration of charged particles (both electrons and protons) at collisionless shocks predicted to exist in the vicinity of solar flares. The existence of standing termination shocks has been examined by flare models and…
Pulsars steadily dissipate their rotational energy via relativistic winds. Confinement of these outflows generates luminous pulsar wind nebulae, seen across the electromagnetic spectrum in synchrotron and inverse Compton emission, and in…
I outline, from a theoretical and somewhat personal perspective, significant features of Pulsar Wind Nebulae as Cosmic Accelerators. I discuss recent studies of Pulsar Wind Nebulae (PWNe). I pay special attention to the recently discovered…
After discussion of observational constraints on the nature of the MHD wind coupling between the Crab Pulsar and the Crab Nebula, the theory of transverse relativistic shock structure is reviewed and applied to the interpretation of the…
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,…
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…
Recent work on the properties of superluminal waves in pulsar winds is summarized. It is speculated that these waves play an important role in the termination shock that divides the wind from the surrounding nebula.
We present a model for magnetic energy dissipation in a pulsar wind nebula. Better understanding of this process is required to assess the likelihood that certain astrophysical transients may be powered by the spin-down of a "millisecond…
An oblique-rotating pulsar generates a relativistic striped wind in a pulsar wind nebula (PWN). The termination shock of the PWN compresses the Poynting-flux-dominated flow and drives magnetic reconnection. By carrying out particle-in-cell…
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…
We model the inner knot of the Crab Nebula as a synchrotron emission coming from the non-spherical MHD termination shock of relativistic pulsar wind. The post-shock flow is mildly relativistic; as a result the Doppler-beaming has a strong…
Accretion disc turbulence is investigated in the framework of the shearing box approximation. The turbulence is either driven by the magneto-rotational instability or, in the non-magnetic case, by an explicit and artificial forcing term in…
Pulsar Wind Nebulae (PWNe) act as calorimeters for the relativistic pair winds emanating from within the pulsar light cylinder. Their radiative dissipation in various wavebands is significantly different from that of their pulsar central…
Synchrotron radiation of ultra-relativistic particles accelerated in a pulsar wind nebula may dominate its spectrum up to gamma-ray energies. Because of the short cooling time of the gamma-ray emitting electrons, the gamma-ray emission zone…
As a shock front interacts with turbulence, it develops corrugation which induces outgoing wave modes in the downstream plasma. For a fast shock wave, the incoming wave modes can either be fast magnetosonic waves originating from…
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…
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…
Rapidly rotating neutron stars blow a relativistic, magnetized wind mainly composed of electron-positron pairs. The free expansion of the wind terminates far from the neutron star where a weakly magnetized pulsar wind nebula forms, implying…