A5016790510- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Gyrotron and Vacuum Electronics Research
- Superconducting Materials and Applications
- Particle Detector Development and Performance
- Photocathodes and Microchannel Plates
- Advanced Radiotherapy Techniques
- Radiation Therapy and Dosimetry
- Magnetic confinement fusion research
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- Optical Systems and Laser Technology
- Laser-Matter Interactions and Applications
- Magneto-Optical Properties and Applications
- Advanced Optical Sensing Technologies
- Photonic and Optical Devices
- Effects of Radiation Exposure
- Microwave Engineering and Waveguides
- Radiation Dose and Imaging
- Advanced X-ray Imaging Techniques
- Spectroscopy and Laser Applications
- Spacecraft and Cryogenic Technologies
- Electromagnetic Compatibility and Measurements
- Aerodynamics and Acoustics in Jet Flows
- Radio Astronomy Observations and Technology
SLAC National Accelerator Laboratory
2002-2022
John Brown University
2017
Menlo School
2004-2015
Linac Coherent Light Source
2007
Stanford Synchrotron Radiation Lightsource
1996-2006
Stanford University
2002
We report on an experiment performing channeling and volume reflection of a high-energy electron beam using quasimosaic, bent silicon (111) crystal at the End Station A Test Beam SLAC. The uses beams 3.35 6.3 GeV. In orientation, deflections 400 μrad for both energies with about 22% efficiency are observed, while in volume-reflection deflection by 120 GeV 80 is observed 86%-95% efficiency. Quantitative measurements efficiency, surface transmission, dechanneling length taken. These first...
We report the production of optically spaced attosecond electron microbunches produced by inverse free-electron-laser (IFEL) process. The IFEL is driven a Ti:sapphire laser synchronized with beam. followed magnetic chicane that converts energy modulation into longitudinal microbunch structure. train characterized observing coherent optical transition radiation (COTR) at multiple harmonics bunching. Experimental results are compared 1D analytic theory showing good agreement. Estimates...
Purpose: To measure radiation dose in a water‐equivalent medium from very high‐energy electron (VHEE) beams and make comparisons to Monte Carlo (MC) simulation results. Methods: Dose polystyrene phantom delivered by an experimental VHEE beam line was measured with Gafchromic films for three 50 MeV two 70 Gaussian of 4.0–6.9 mm FWHM compared corresponding MC‐simulated distributions. MC the calculated EGSnrc/BEAMnrc DOSXYZnrc codes based on setup. Additionally, effect 2% energy measurement...
A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This has many advantageous properties over previously studied schemes, including being significantly shorter a given energy having better bandwidth. Experimental results from ATF2 accelerator at KEK are presented that validate operating principle such by demonstrating demagnification 1.3 GeV electron beam down to below 65 nm height...
We present a multimode $X$-band rf pulse compression system suitable for TeV-scale electron-positron linear collider such as the Next Linear Collider (NLC). The NLC main linac operating frequency is 11.424 GHz. A single unit required to produce 400 ns pulses with 475 MW of peak power. Each should power approximately 5 m accelerator structures. design consists two 75 klystrons and dual-moded resonant-delay-line that produces flat output pulse. components are all overmoded, most designed...
For high luminosity in electron-positron linear colliders, it is essential to generate low vertical emittance beams. We report on the smallest achieved single-bunch-mode operation of Accelerator Test Facility, which satisfies requirement x-band collider. The emittances were measured with a laser-wire beam-profile monitor installed damping ring. bunch length and momentum spread beam also recorded under same conditions. rms at intensity 4 pm energy 1.3 GeV, corresponds normalized 1.0x1.0(-8)...
We report generation of density modulation at terahertz (THz) frequencies in a relativistic electron beam through laser the longitudinal phase space. show that by modulating energy distribution with two lasers, difference frequency lasers can be generated after passes chicane. In this experiment, around 10 THz was down-converting an 800 nm and 1550 laser. The central tuned varying wavelengths, chirp, or momentum compaction This technique applied to accelerator-based light sources for...
In this article we demonstrate the net acceleration of relativistic electrons using a direct, in-vacuum interaction with laser. experiment, an electron beam from conventional accelerator is first energy modulated at optical frequencies in inverse-free-electron-laser and bunched chicane. This followed by second stage to obtain acceleration. The phase between stages monitored controlled order scan accelerating observe deceleration. Phase jitter measurements indicate control...
The Accelerator Test Facility 2 (ATF2) is a scaled demonstrator system for final focus beam lines of linear high energy colliders. This paper describes the resolution cavity position monitor (BPM) system, which part ATF2 diagnostics. Two types BPMs are used, C-band operating at 6.423 GHz, and S-band 2.888 GHz with an increased aperture. cavities, electronics, digital processing described. attenuators was determined to be approximately 250 nm 1 m system. Without attenuation best recorded 27 nm.
An eight-cavity, 1.3 GHz, SLAC linac coherent light source II High Energy cryomodule was assembled and tested at Fermilab to verify performance before the start of production. Its cavities were processed with a novel nitrogen doping treatment improve gradient performance. The modified protocol process sporadic quenches, which observed in Linac Coherent Light Source production cryomodules are attributed multipacting. Dedicated vertical test experiments support attribution verification...
Electron beams with the lowest, normalized transverse emittance recorded so far were produced and confirmed in single-bunch-mode operation of Accelerator Test Facility at KEK. We established a tuning method damping ring which achieves small vertical dispersion x-y orbit coupling. The was less than 1% horizontal emittance. At zero-intensity limit, 2.8 x 10(-8) rad m beam energy 1.3 GeV. high intensity, strong effects intrabeam scattering observed, had been expected view extremely particle...
During the past five years, there has been an concerted program at SLAC and KEK to develop accelerator structures that meet high gradient (65 MV/m) performance requirements for Next Linear Collider (NLC) Global (GLC) initiatives. The design resulted is a 60-cm-long, traveling-wave structure with low group velocity 150 degree per cell phase advance. It average iris size produces acceptable short-range wakefield, dipole mode damping detuning adequately suppresses long-range wakefield. More...
ATF2 is a final-focus test beam line which aims to focus the low emittance from ATF damping ring vertical size of about 37 nm and demonstrate nanometer level stability. Several advanced diagnostics feedback tools are used. In December 2008, construction installation were completed commissioning started, supported by an international team Asian, European, U.S. scientists. The present status first results described.
Beam size estimates made using beam-beam deflections are used for optimization of the Stanford Linear Collider (SLC) electron-positron beam sizes. Typical sizes and intensities expected 1996 operations 2.1 × 0.6 μm (x, y) at 4.0 1010 particles per pulse. Conventional profile monitors, such as scanning wires, fail charge densities well below this. The laser-based monitor uses a finely-focused 350-nm wavelength tripled YLF laser pulse that traverses particle path about 29 cm away from e+/e−...
The SLAC Linac can deliver damped bunches with ILC parameters for bunch charge and length to End Station A. A 10Hz beam at 28.5 GeV energy be delivered there, parasitic PEP-II operation. We plan use this facility test prototype components of the Beam Delivery System Interaction Region. discuss our plans Test Facility preparations carrying out experiments related collimator wakefields spectrometers. also an interaction region mockup investigate effects from backgrounds beam-induced...
Beam size estimates made using beam-beam deflections are used for optimization of the Stanford Linear Collider (SLC) electron-positron beam sizes. and intensity goals 1996 were 2.1 x 0.6 μm (x,y) at 4.0x10 10 particles per pulse. Conventional profile monitors, such as scanning wires, fail charge densities well below this. Since deflection does not provide single information, another method is needed Interaction Region (IP) optimization. The laser based monitor uses a finely focused 349 nm....