Terahertz radiation (THz)-based electron acceleration has the potential as a technology for driving next-generation, compact ultrafast and ultrabright x-ray sources. Dephasing is one of key problems that prevent long THz–electron interaction lengths in sub- to few-MeV range, where velocities vary significantly during high-field acceleration. Here, we present phase-shifter design with double vac...

Laser-powered acceleration of charged particles promises extraordinary acceleration gradients due to the immense power available from lasers. This possibility has led to many proposed structures for laser acceleration; however, the field of vacuum laser acceleration is almost wholly unexplored experimentally. Recent advances in laser efficiency and phase synchronization have made possible a pra...

Historically, direct acceleration of charged particles by electromagnetic fields has been limited by diffraction, phase matching, and material damage thresholds. A recently developed plasma micro-optic [B. Layer, Phys. Rev. Lett. 99, 035001 (2007)] removes these limitations and promises to allow high-field acceleration of electrons over many centimeters using relatively small femtosecond lasers...

Beam commissioning in the KEK Digital Accelerator, which is a small scale induction synchrotron (IS), has been conducted since the middle of 2011. Longitudinal beam motion in the induction synchrotron, utilizing induction cells (IC) for acceleration and confinement, is characterized as barrier bucket acceleration. A tracking code has been developed to understand the longitudinal motion affected...

A novel approach of laser-driven acceleration with Bessel beam is presented in this paper. Bessel beam, in contrast to the Gaussian beam, demonstrates “diffractionfree” characteristics in its propagation, which implies potential in laser-driven acceleration. A configuration of Bessel beam truncated by a set of annular slits makes several special regions in its travelling path, where the laser f...

Muon acceleration is one of the more difficult stages to develop for a Neutrino Factory or Muon Collider. The large transverse and longitudinal admittances which must be designed into the system and the rapidity with which acceleration must take place because of muon decay preclude the use of conventional synchrotron design. The approach here employs fixed-field architectures for muon accelerat...

Spatiotemporal convergence and two-dimensional (2-D) neural tuning have been proposed as a major neural mechanism in the signal processing of linear acceleration. To examine this hypothesis, we studied the firing properties of primary otolith afferents and central otolith neurons that respond exclusively to horizontal linear accelerations of the head (0.16-10 Hz) in alert rhesus monkeys. Unlike...