We study the magnetic reconnection for relativistic plasma in the framework of magnetohydrodynamics and by means of the Particle-In-Cell (PIC) simulation. In the former approach, the magnetic fields are assumed to reconnect steadily inside the diffusion region as assumed in the conventional Sweet-Parker model. The model takes account of the pressure gradient between the diffusion and outflow re...

The z = 4.591 quasar PC 1415+3408 exhibits very strong associated metal–line absorption from the N V λλ1238, 1242, Si IV λλ1393, 1402, and C IV λλ1548, 1550 doublets spanning the velocity interval −1700 ≤ v ≤ 0 km s−1. Also present, are detached absorption troughs in N V and C IV spanning −5000 ≤ v ≤ −3000 km s−1; this is characteristic of broad absorption line (BAL) quasars, but the small over...

The dynamical behavior of an acoustic polaron in typical non-degenerate conjugated polymer, polydiacetylene, is numerically studied by using Su-Schrieffer-Heeger’s model for the one dimensional electron-lattice system. It is confirmed that the velocity of a polaron accelerated by a constant electric field shows a saturation to a velocity close to the sound velocity of the system, and that the w...

The Ultraviolet Coronagraph Spectrometer (UVCS) aboard the Solar and Heliospheric Observatory (SOHO) has revealed strong kinetic anisotropies and extremely large perpendicular temperatures of heavy ions in the extended solar corona. These observations have revived interest in the idea that the high-speed solar wind is heated and accelerated by the dissipation of ion cyclotron resonant Alfvén wa...

We use proper motions and parallaxes from the new reduction of Hipparcos data and Geneva-Copenhagen radial velocities for a complete sample of ∼ 15 000 main-sequence and subgiant stars, and new Padova isochrones to constrain the kinematics and starformation history of the solar neighbourhood. We rederive the solar motion and the structure of the local velocity ellipsoids. When the principal vel...

Cerenkov wake amplification can be used as an accelerating scheme, in which a trigger bunch of electrons propagating inside a cylindrical waveguide filled with an active medium generates an initial wake field. Due to the multiple reflections inside the waveguide, the wake may be amplified significantly more strongly than when propagating in a boundless medium. Sufficiently far away from the tri...