A5035304613- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Gyrotron and Vacuum Electronics Research
- Superconducting Materials and Applications
- Advanced X-ray Imaging Techniques
- Electromagnetic Simulation and Numerical Methods
- Photocathodes and Microchannel Plates
- Magnetic confinement fusion research
- Particle Detector Development and Performance
- Advancements in Photolithography Techniques
- Physics of Superconductivity and Magnetism
- Strong Light-Matter Interactions
- Lightning and Electromagnetic Phenomena
- Electrostatic Discharge in Electronics
- Vibration and Dynamic Analysis
- Laser-Plasma Interactions and Diagnostics
- Distributed and Parallel Computing Systems
- Particle physics theoretical and experimental studies
- X-ray Spectroscopy and Fluorescence Analysis
- Dark Matter and Cosmic Phenomena
- Photonic and Optical Devices
- Electron and X-Ray Spectroscopy Techniques
- Laser Design and Applications
- Advanced Optical Sensing Technologies
- Radiation Detection and Scintillator Technologies
Brookhaven National Laboratory
2014-2024
Brookhaven College
2023
Helmholtz-Zentrum Berlin für Materialien und Energie
2022
National Synchrotron Light Source II
2002-2016
SLAC National Accelerator Laboratory
1995-2015
RIKEN BNL Research Center
2006-2007
Stanford Synchrotron Radiation Lightsource
1995-2003
Stanford University
1995-2002
Menlo School
1995
A new experiment is described to detect a permanent electric dipole moment of the proton with sensitivity $10^{-29}e\cdot$cm by using polarized "magic" momentum $0.7$~GeV/c protons in an all-electric storage ring. Systematic errors relevant are discussed and techniques address them presented. The measurement sensitive physics beyond Standard Model at scale 3000~TeV.
Static electric dipole moments of nondegenerate systems probe mass scales for physics beyond the Standard Model well those reached directly at high energy colliders. Discrimination between different models, however, requires complementary searches in atomic-molecular-and-optical, nuclear and particle physics. In this report, we discuss current status prospects near future a compelling suite such experiments, along with developments needed encompassing theoretical framework.
The generation of brilliant, stable, and broadband coherent synchrotron radiation (CSR) in electron storage rings depends strongly on ring rf system properties such as frequency gap voltage. We have observed intense at frequencies approaching the THz regime produced by MIT-Bates South Hall Ring, which employs a high-frequency $S$-band system. measured CSR spectral intensity enhancement with 2 mA stored current was up to 10 000 times above background for wave numbers near $3\text{ }\text{...
Usual treatments of resistive wall effects in accelerators are limited to the normal skin effect regime electrical conductivity metals. Therefore they do not generally apply situations when beam-exposed metallic surfaces vacuum chamber held at cryogenic temperatures, where simple metals exhibit anomalous behavior. These occasionally occur with cold-bore devices, such as small-gap superconducting undulators. The amount resistivity material can be substantial significantly influence beam...
Advanced light sources using relativistic electrons rely on coherent emission from high-density (compressed) beams. These beams, typically produced by photoinjected linear accelerators, can suffer uncontrolled microbunching instabilities that are difficult to manage, since a complete understanding of their growth due space charge and other wakefields is lacking. Here we present the first systematic measurements instability electron beams premodulated in controlled fashion. By comparing...
We present calculations of the longitudinal wakefields at cryogenic temperatures for extremely short bunches, characteristic modern x-ray free electron lasers. The are based on equations surface impedance in regime anomalous skin effect metals. This paper extends and complements an earlier analysis B. Podobedov, Phys. Rev. ST Accel. Beams 12, 044401 (2009). into region very high frequencies associated with bunch lengths micron range. study detail case a rectangular distribution parameters...
We describe a proposal to search for an intrinsic electric dipole moment (EDM) of the proton with sensitivity \targetsens, based on vertical rotation polarization stored beam. The New Physics reach is order $10^~3$TeV mass scale. Observation EDM provides best probe CP-violation in Higgs sector, at level that may be inaccessible electron-EDM experiments. improvement $\theta_{QCD}$, parameter crucial axion and dark matter physics, about three orders magnitude.
Measurements of the beam's bunch length in Cornell Electron-Positron Storage Ring (CESR) have been made using a streak camera. The camera uses visible synchrotron radiation produced by beam to measure its longitudinal distribution. A description CESR, experimental setup, used, and systematic errors analysis techniques are described this paper. dependence distribution on current accelerating rf voltage for single CESR was measured compared with theoretical model CESR. vacuum chamber impedance...
We present the first experimental studies of initial source electron beam microbunching instability in a free laser (FEL) injector. By utilizing for transform-limited pulse at photocathode, we eliminated laser-induced National Synchrotron Light Source Development Laboratory (SDL). The detailed measurements resulting led us to conclude that, SDL, arising from shot noise is not amplified any significant level, thereby allowing set an upper limit on modulation depth noise. Our analysis...
The coherent beam-beam interaction in the absence of Landau damping is studied with a computer simulation four space-charge-compensated colliding beams. Results are presented for modes, phase space structures, widths, and growth rates resonances. These results compared solutions Vlasov equation, measurements made at Dispositif de Collisions dans l'Igloo (DCI) storage ring Orsay, France, which operated
New low-impedance vacuum chambers were installed in the SLC damping rings for 1994 run after finding a single bunch instability with old chamber. Although threshold is lower new chamber, less severe, and we are now routinely operating at intensities of 4.5/spl times/10/sup 10/ particles per (ppb) compared to 3/spl ppb 1993. The chamber upgrade described, measurements length, energy spread, frequency time domain signatures presented.
We present a new method to accurately calculate point-charge geometric wakefields and/or short-bunch wake potentials from due much longer bunch, typically obtained with time-domain electromagnetic (EM) field solver. By allowing long bunch in the EM solver, this can significantly reduce need for computer resources as well drastically shorten computing time. After explaining we give examples of longitudinal wakefield calculations several 2D accelerator structures various complexity.
We determine the impedance of a cylindrical metal tube (resistor) radius $a$, length $g$, and conductivity $\ensuremath{\sigma}$ attached at each end to perfect conductors semi-infinite length. Our main interest is in asymptotic behavior high frequency $(k\ensuremath{\gg}1/a)$. In equilibrium regime, $k{a}^{2}\ensuremath{\ll}g$, per unit accurately described by well-known result for an infinite with $\ensuremath{\sigma}$. transient $k{a}^{2}\ensuremath{\gg}g$, where contribution transition...
We determine the low frequency transverse impedance of axially symmetric tapered structures. Higher-order perturbation theory is used to improve previous estimates due Yokoya and Stupakov. For linear tapers, accurate numerical results are obtained using ABCI electromagnetic simulation code. Based upon insight gained from calculations, we introduce a simple parametrization that provides an excellent fit all our data---including cases with gradual steep tapers as well large small change in...
We study the transverse geometric impedance of elliptical cross-section tapers in low-frequency ``inductive regime.'' have followed a dual approach: computer simulations been carried out using finite element electromagnetic code GDFIDL and analytic results for dipolar quadrupolar components derived extending perturbation technique introduced by Stupakov. Our work provides new insight into behavior axially asymmetric tapered structures at low frequency. In particular, we clarify frequency...
National Synchrotron Light Source II (NSLS-II) is a new third-generation storage ring light source at Brookhaven Laboratory. The design calls for small horizontal emittance (<1 nm-rad) and diffraction-limited vertical 12 keV (8 pm-rad). Achieving low value of the beam size will enable novel user experiments with nm-range spatial meV-energy resolution. high-brightness NSLS-II lattice has been realized by implementing 30-cell double bend achromatic cells producing 2 nm rad then halving it...
We describe a major paradygm shift in the approach to production of synchrotron radiation This change will considerably improve scientific capabilities light sources. introduce plans for an upgrade National Synchrotron Light Source (NSLS). be based on Photoinjected Energy Recovering Linac (PERL). machine emerges from union two technologies, laser-photocathode RF gun (photoinjector) and superconducting linear accelerators with beam energy recovery (Energy Linac). The bring NSLS users many new...
There exist analytical approximations that express the transverse geometric impedance of tapered transitions in inductive regime as a functional transition boundary and its derivatives. Assuming initial final cross-sections length are fixed, one can minimize these functionals by appropriate choice variation with longitudinal coordinate. In this paper we numerically investigate how well works for cases optimized circular, elliptical rectangular geometry running ABCI, ECHO, GdfidL EM field...
The National Synchrotron Light Source II (NSLS-II) is a state of the art 3 GeV third generation light source at Brookhaven Laboratory. During spring/ summer 2014, storage ring was commissioned up to 50 mA without insertion devices. In fall we began commissioning project beamlines, which included seven devices on six ID ports. Beamlines IXS, HXN, CSX-1, CSX-2, CHX, SRX, and XPD-1 consist elliptically polarized undulator (EPU), damping wigglers (DW) in-vacuum undulators (IVU) covering from VUV...