Phase noise in the RF master oscillator driving synchrotron oscillations of the beam has been identified as one of the dominant sources of noise in the infrared beamline at the Advanced Light Source. We present measurements of the effect of the electron beam motion in a Fourier transform interferometer (FTIR) detector. This form of detector may be sensitive to very small beam motions.

The HERMES hydrogen and deuterium nuclear-polarized gas targets have been in use since 1996 with the polarized electron beam of HERA at DESY to study the spin structure of the nucleon. Polarized atoms from a Stern-Gerlach Atomic Beam Source are injected into a storage cell internal to the HERA electron ring. Atoms diffusing from the center of the storage cell into a side tube are analyzed to de...

The accumulation of water and hydrocarbons molecules on pure Au smooth surfaces were monitored during 100 eV electron bombardment at various beam current levels. Our studies showed that these low energy electrons could accelerate the physical adsorption processes of the gaseous contaminant molecules on the mirror surface. The 100 eV electron beam was used to provide a rough simulation of the se...

Executive Summary We propose a program of study of the interaction of electrons and photons in fields approaching the critical QED field strength of an electron rest energy per Compton wavelength. This can be achieved in collisions between the picosecond pulses of a teraWatt laser and a 50-GeV electron beam. The phenomena accessible to study include nonlinear Compton scattering , trident produc...

The Beam Scraping Monitor (BSM) is used to detect small amounts of beam loss in Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF). The BSM acts as an early warning system that alerts CEBAF operators when the beam loss exceeds 10 to 20 nA. This allows the CEBAF operators to adjust the beam orbit before beam loss reaches the Beam Loss Accounting (BLA) system threshold (present...

Introduction: Intraoperative electron radiation therapy (IOERT) is one of the cancer treatment techniques that delivers high doses to tumor bed during surgery. IOERT can be performed by either conventional LINACs or dedicated IORT accelerators such as LIAC (Light Intraoperative Accelerator). Two types of applicators can be used with LIAC dedicated accelerator including conventi...

A new class of synchrotron light sources, based on the use of superconducting electron linear accelerators and beam recirculation with energy recovery, is currently under active consideration. The injectors for such accelerators must deliver high brightness electron beams with appropriate RF time structure and the full average beam current. Various photoemission cathodes have been demonstrated ...

Photocathode rf guns depend on mode locked laser systems to produce an electron beam at a given phase of the rf. In general, the laser pulse is less than σz = 10° of rf phase in length and the required stability is on the order of ∆φ = 1°. At 90 GHz (W-band), these requirements correspond to σz = 333 fsec and ∆φ = 33 fsec. Laser system with pulse lengths in the fsec regime are commercially avai...

When the PDD (percentage depth dose) in the megavoltage beams is measured in the water phantom using the dosimetry system, the polarity and ion recombination effects of ionization chambers with depth in water are not usually taken into consideration. The polarity and ion recombination effects may vary depending on the radiation type and spectrum, which vary with depth in water [1-4]. If those e...

The Brookhaven Accelerator Test Facility (ATF) is a dedicated user facility for accelerator physicists. Its design is optimized to explore laser acceleration and coherent radiation production. To characterize the lowemittance, picoseconds long electron beam produced by the ATF's photocathode RF gun, we have installed electron beam profile monitors for transverse emittance measurement, and devel...