Related papers: The Devil is in the Details: Compact Structures in…
Pulsars are known to be efficient accelerators that produce copious amounts of relativistic particles and inject them into the Galactic medium. The radiation emitted by such a pulsar wind can be seen from radio through gamma-rays as a…
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…
Based on the expected population of core collapse supernova remnants and the huge number of detected pulsars in the Galaxy, still representing only a fraction of the real population, pulsar wind nebulae are likely to constitute one of the…
Since various structural components of planetary nebulae manifest themselves differently, a combination of optical, infrared, submm, and radio techniques is needed to derive a complete picture of planetary nebulae. The effects of projection…
A significant fraction of massive stars move at speed through the interstellar medium of galaxies. After their death as core collapse supernovae, a possible final evolutionary state is that of a fast rotating magnetised neutron star,…
Young pulsars spin incredibly quickly, but are also slowing down at a very rapid rate. This process carries away enormous amounts of energy from the star in the form of a relativistic wind. Through the high resolution now offered by the…
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…
We report on a Chandra observation of the Crab Nebula that gives the first clear view of the faint boundary of the Crab's X-ray-emitting Pulsar Wind Nebula, or PWN. There is structure in all directions. Fingers, loops, bays, and the South…
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…
The very high energy (VHE) gamma-ray emission reported from a number of pulsar wind nebulae (PWNe) is naturally explained by the inverse Compton scattering of multi-TeV electrons. However, the physical dimensions of some gamma-ray-emitting…
Planetary nebulae (PNe) are known to possess a variety of small-scale structures that are usually in a lower ionization state than the main body of the nebulae. The morphological and kinematic properties of these low-ionization structures…
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.
Recent X-ray observations of young rotation-powered pulsars are providing an unprecedented detailed view of pulsar wind nebulae. For the first time, coherent emission features involving wisps, co-aligned toroidal structures, and axial jets…
We present an investigation of the spectral and spatial structure of the X-ray emission from 3C 58 based on a 350 ks observation with the Chandra X-ray Observatory. This deep image, obtained as part of the Chandra Large Project program,…
The vast majority of Pulsar Wind Nebulae (PWNe) present in the Galaxy is formed by middle-aged systems characterized by a strong interaction of the PWN itself with the supernova remnant (SNR). Unfortunately, modelling these systems can be…
Some fast-moving pulsars, like the Guitar and the Lighthouse, exhibit asymmetric non-thermal emission features that extend well beyond their ram pressure confined pulsar wind nebulae (PWNe). Using 3D relativistic simulations we explain…
We present new results of a program aimed at studying the physical properties, origin and evolution of those phenomena which go under the somewhat generic definition of "low-ionization, small-scale structures in PNe". We have obtained…
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…
Pulsar Wind Nebulae (PWNe) represent the most numerous population of TeV sources in our Galaxy. These sources, some of which emit very-high-energy (VHE) gamma-rays, are believed to be related to the young and energetic pulsars that power…
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…