An overview is given of the physics issues relevant to the plasma wakefield accelerator, the plasma beat-wave accelerator, the laser wakefield accelerator, including the self-modulated regime, and wakefield accelerators driven by multiple electron or laser pulses. Basic properties of linear and nonlinear plasma waves are discussed, as well as the trapping and acceleration of electrons in the pl...

Electron beam bunching in the optical wavelength was observed experimentally for the first time at the Brookhaven Accelerator Test Facility(ATF) using the Inverse Free Electron(IFEL) accelerator. The micro-bunched electron beam has been studied by measuring the coherent transition radiation (CTR). We have experimentally observed a quadratic dependency of the CTR signal with the charge of the el...

Construction of a compact 2.4 Tm Cooler Injector synchrotron (CIS) to injection intense polarised proton and deuteron beams into the IUCF 3.6 Tm electron cooled storage ring (Cooler) is complete. Beam commissioning began in 1997 with unpolarized H strip injection and progressed to the extraction of 210 MeV protons from CIS and the injection of 10 protons at 200 MeV into the Cooler for experimen...

The MIT-Bates Linear Accelerator has completed a major nuclear physics experiment using high duty factor electron beam resonantly extracted from the South Hall Ring. Average currents up to 8 μA at energies from 569 to 950 MeV were delivered to the new Out Of Plane Spectrometer System, with typical duty factors of 60%. Throughput efficiencies, measured as the ratio of beam current injected into ...

The generation of an ultrashort relativistic electron bunch from a strong laser-plasma interaction have been studied by particle-in-cell simulations and observed experimentally. The electron beam was generated from the plasma created by focusing a Ti: sapphire 12 TW (tera watt) laser pulse at the edge of helium gas jet expanded into the vacuum from a pulsed supersonic nozzle. The laser pulse du...

The construction of a third-generation light source has been proposed at Tohoku University. The emittance is 7.3 nm rad at the nominal beam energy, 1.5 GeV. The circumference is 194 m. The ring consists of 12 double-bend achromatic cells. Ten of 12 dispersion-free long straight sections are 5 m long and will be used for insertion devices and some accelerator components. The remaining two are ea...

The Cornell Electron Storage Ring has been reconfigured as a test accelerator (CesrTA) for damping ring R&D for the International Linear Collider (ILC). As part of the research effort, low emittance tuning techniques are being developed with a goal of achieving a vertical emittance approaching that of the ILC damping rings. These techniques include gain mapping to characterize beam position mon...

We present a plan for conversion of the Cornell Electron Storage Ring, CESR, to a high luminosity source which will increase the world data set in the range 3<Ecm<5 GeV by factors of 20 to 100 in the next four years. Accelerator physics issues related to high luminosity operation in this energy range have been examined in detail, both in computational and experimental programs. We discuss resul...

A Michelson interferometer was installed at the femtosecond (fs) terahertz (THz) Accelerator of Pohang Accelerator Laboratory(PAL) to measure a subpicosecond order electron bunch length. To measure an ultra-short electron bunch length, we use reconstruction process and fast fourier transform. Currently, we are generating THz radiation with the pulse energy of 7μJ by means of coherent transition...

The Colorado State University (CSU) Accelerator Facility will include a 6-MeV L-Band electron linear accelerator (linac) with a free-electron laser (FEL) system capable of producing Terahertz (THz) radiation, a laser laboratory, a microwave test stand, and a magnetic test stand. The photocathode drive linac will be used in conjunction with a hybrid undulator capable of producing THz radiation. ...