A reduced approach to modeling the electromagnetic Weibel instability and relativistic electron beam transport in collisionless background plasma is developed. Beam electrons are modeled by macroparticles and the background plasma is represented by electron fluid. Conservation of generalized vorticity and quasineutrality of the plasma-beam system are used to simplify the governing equations. Th...

We review the formulation of the problem of the electromagnetic self-interaction of a relativistic charged particle in the framework of the manifestly covariant classical mechanics of Stueckelberg, Horwitz, and Piron. The gauge fields of this theory, in general, cause the mass of the particle to change. We show that the nonlinear Lorentz force equation for the self-interaction resulting from th...

On 10 January 1997 a magnetic cloud of a coronal mass ejection impinged upon the earth magnetosphere and caused considerable variations of the relativistic electron population in the earth’s outer radiation belt in the following days. Data obtained with radiation detectors on board a pair of satellites, STRV-1a and STRV-1b in a nearly equatorial geostationary transfer orbit show that the electr...

Models for the integrated relativistic electron population in clusters of galaxies are presented. The results depend on the history of electron acceleration in the cluster. If there is no present particle acceleration or other sources, then no high energy electrons (γ >∼ 300, E >∼ 150 MeV) should be present due to inverse Compton (IC) losses. High energy electrons are present if particle accele...

Recently, a scheme for producing ideal uniformly filled ellipsoidal beam distributions, which depends on the strong longitudinal expansion of an initially very short beam under its own space charge forces, has been demonstrated at the UCLA Pegasus Laboratory. Here we present further work on the characterization of this novel regime of operation of a photoinjector. In particular we study the sen...

— There is a strong interest in the development of single shot diagnostics of fs relativistic electron bunches within research areas including THz sources of radiation. The goal of the work presented is to understand the properties of coherent Smith-Purcell radiation to enable the reconstruction of the longitudinal profile of a fs-long electron bunch.

Although the possibility of a low energy cut-off (LEC) of the relativistic electron population (Emin ∼ 0.1 GeV) in the different components of radio galaxies has been discussed in the literature, from both theoretical and observational viewpoints, its possible role in causing a distinct spectral flattening, and thus reducing the apparent brightness temperature of the radio nucleus, has thus far...

A proof of principle experiment is underway at the UCLA Neptune laboratory to test the concept of generating linearly ramped relativistic electron bunches (rising in density from head to tail followed by a sharp cutoff) by using a sextupole-corrected dogleg section as a bunch compressor. Bunches with this structure have been predicted to be ideal for use as a plasma wakefield drive beam. The di...