The end effect in a bunched beam is caused by the space-charge forces, which accelerate particles at the bunch head and decelerate particles at the bunch tail. It occurs in high-current linear accelerators and rings [1]. In the University of Maryland Electron Ring (UMER) project [2,3,4], the energy of particles at the very ends of a rectangular bunch is 15% different from that of the main part ...

The effect of ultrafast electron beam bunch dynamics on single shot electro-optic sampling detection schemes is examined. It is shown that ultrashort electron bunch fields of adequate magnitude can dynamically impose additional bandwidth on laser probe pulses. The significance of this effect is evaluated by comparing the dynamics of the laser probe to that of the nonradiative field of a single ...

In this article we study effects of microbunch cooperative electromagnetic radiation in a bend on transverse beam dynamics. An overtaking radiative interaction between different parts of the bunch results in three major forces variable along the bunch. Longitudinal force leads to energy loss and causes the bunch emittance growth in the bend due to the dispersion effect. Radial force consists of...

Electron bunches with charge densities ρ of the order of 102 to 103 [nC/cm3], energies between 20. and 100. [MeV], peak current > 100 [A], bunch lengths between 0.3 and 1.8 [cm], and bunch charge of 2.0 to 20. [nC] are relevant to the design of Free Electron Lasers and future linear colliders. In this paper we present the results of numerical simulations performed with a particle in a cell (pic...

With the high intensity, low emittance beams needed to reach the luminosity goals of the linear collider, beam size monitoring will play an important role in machine operation. In the damping rings synchrotron radiation (SR) emitted by the bunch can provide a means of measuring transverse bunch size and shape. With suitable imaging and high speed detection of the SR, bunch size, shape, and posi...

We described here the way of production of ≤ 100 fs bursts of X and gamma radiation by Compton backscattering of a laser bunch which have been swept along the electron trajectory. In the method described the time duration of the secondary radiation does not depend on electron bunch length and is shorter than duration of the primary laser bunch by factor 1/ –the number of resolved spots of sweep...

A method for computing transverse multibunch growth rates and frequency shifts in rings, which has been described previously [1, 2], is applied to the PEP-II B factory. The method allows multibunch modes with different internal-bunch oscillation modes to couple to one another, similar to single-bunch mode coupling. Including coupling between the multibunch modes gives effects similar to those s...

PILATUS X-ray detectors are in operation at many synchrotron beamlines around the world. This article reports on the characterization of the new PILATUS3 detector generation at high count rates. As for all counting detectors, the measured intensities have to be corrected for the dead-time of the counting mechanism at high photon fluxes. The large number of different bunch modes at these synchro...

This paper presents the Abductive LogIc Agent System (ALIAS, for short), a multi-agent architecture based on cooperating intelligent logic agents. Agents in ALIAS are grouped into bunches; each bunch represents an agora where agents together discuss about common arguments. ALIAS agents can ramble from bunch to bunch at runtime, thus collecting information (i.e. agent's experience) derived from ...