A5007435683- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Particle physics theoretical and experimental studies
- Particle Detector Development and Performance
- Atomic and Subatomic Physics Research
- Quantum Chromodynamics and Particle Interactions
- Gyrotron and Vacuum Electronics Research
- High-Energy Particle Collisions Research
- Electron and X-Ray Spectroscopy Techniques
- Atomic and Molecular Physics
- Advanced Frequency and Time Standards
- Advanced X-ray Imaging Techniques
- Cold Atom Physics and Bose-Einstein Condensates
- Magnetic confinement fusion research
- Radiation Detection and Scintillator Technologies
- Dark Matter and Cosmic Phenomena
- Advanced Electron Microscopy Techniques and Applications
- Photocathodes and Microchannel Plates
- Plasma Diagnostics and Applications
- Crystallography and Radiation Phenomena
- Nuclear Physics and Applications
- Radiation Therapy and Dosimetry
- Solar and Space Plasma Dynamics
- Quantum Information and Cryptography
Fermi National Accelerator Laboratory
2016-2025
Electronics for Imaging (United States)
2023
Fermi Research Alliance
2010-2021
Cockcroft Institute
2021
University of Manchester
2021
University of Chicago
2020-2021
Brookhaven National Laboratory
2020
RadiaBeam Technologies (United States)
2019
Lawrence Berkeley National Laboratory
2018
European Organization for Nuclear Research
2012-2017
The Integrable Optics Test Accelerator (IOTA) is a storage ring for advanced beam physics research currently being built and commissioned at Fermilab. It will operate with protons electrons using injectors momenta of 70 150 MeV/c, respectively. program includes the study nonlinear focusing integrable optical lattices based on special magnets electron lenses, dynamics space-charge effects their compensation, stochastic cooling, several other experiments. In this article, we present design...
A novel concept of controlled halo removal for intense high-energy beams in storage rings and colliders is presented. It based on the interaction circulating beam with a 5-keV, magnetically confined, pulsed hollow electron 2-m-long section ring. The electrons enclose beam, kicking particles transversely leaving core unperturbed. By acting as tunable diffusion enhancer not hard aperture limitation, collimator extends conventional collimation systems beyond intensity limits imposed by...
The cross section for the reaction $\overline{p}\stackrel{\ensuremath{\rightarrow}}{p}{e}^{+}{e}^{\ensuremath{-}}$ has been measured at $s=8.8,$ $10.8,$ $12.4,$ $13.1,$ and $14.4 {\mathrm{GeV}}^{2}$ by Fermilab experiment E835. A non-magnetic spectrometer is used to identify ${e}^{+}{e}^{\ensuremath{-}}$ final states generated antiproton beam intersecting an internal hydrogen gas jet target. From analysis of 144 observed events, new high-precision measurements proton magnetic form factor...
We report evidence for the hc state of charmonium in its ηcγ decay mode and lack J/ψπ0 mode. studied these channels p¯p annihilations near center gravity PJ3 states, where was reported by E760, our previous experiment, at 3526.2±0.15±0.2 MeV, with ΓR≤1 MeV. observe an event excess 3526 Testing null hypothesis a linearly varying background cross section against alternate that includes resonance we reject P∼0.001. The mass is 3525.8±0.2±0.2 MeV width ≤1 estimate 10.0±3.5<Γp¯pBηcγ<12.0±4.5 eV,...
Fermilab experiment E835 has measured the cross section for reaction p̄p→e+e− at s=11.63, 12.43, 14.40 and 18.22 GeV2. From analysis of 66 observed events new high-precision measurements proton magnetic form factor are obtained.
Collimation of proton and antiproton beams in the Tevatron collider is required to protect CDF D0 detectors minimize their background rates, keep irradiation superconducting magnets under control, maintain long-term operational reliability, reduce impact beam-induced radiation on environment. In this article we briefly describe design, practical implementation performance collimation system, methods control transverse longitudinal beam halo two novel techniques tested Tevatron.
Excitation functions for $^{208--211}\mathrm{Fr}$ isotopes produced in the $^{18}\mathrm{O}+^{197}\mathrm{Au}$ fusion-evaporation reaction have been measured at ${E}_{\mathrm{lab}}=75\text{--}130$ MeV via characteristic $\ensuremath{\alpha}$ decays by means of an electrostatic deflector and a semiconductor detector. Data compared with calculations giving barrier-passing (capture) cross sections probabilities compound nucleus decay into different channels according to standard statistical model.
The time evolution of beam losses during a collimator scan provides information on halo diffusion and population. This is an essential input for machine performance characterization the design collimation systems. Beam measurements in CERN Large Hadron Collider were conducted through scrapings dedicated study first at 4 TeV. Four scans performed with two collimators, vertical plane 1 horizontally 2, before after bringing beams into collisions. Inward outward steps performed. A model was used...
We report on a study of the angular distributions in radiative decay χc1 and χc2 states formed p¯p annihilations. These depend dynamics formation process multipole structure decay. Using 2090 5908 events, we have measured fractional magnetic quadrupole amplitude to be a2(χc1)≃M2/E1=0.002±0.032, a2(χc2)=−0.093−0.041+0.039. also square helicity 0 B02=0.13±0.08. Received 3 July 2001DOI:https://doi.org/10.1103/PhysRevD.65.052002©2002 American Physical Society
Abstract Electrons lenses produce a high-intensity electron beam and have variety of applications to circular hadron accelerators. Electron beams different transverse cross sections distributions may be designed, depending on the desired application, they are produced steered along orbit beam, overlapping with it for typical distances few meters before being deflected away disposed of. Hollow find collimation machines like CERN Large Hadron Collider (LHC). Such devices can integrated in...
We report the branching ratios of ${\ensuremath{\chi}}_{c2}{(1}^{3}{P}_{2})$ and ${\ensuremath{\chi}}_{c0}{(1}^{3}{P}_{0})$ charmonium resonances to two photons using event samples collected by Fermilab experiment E835 in reactions $\overline{p}\stackrel{\ensuremath{\rightarrow}}{p}{\ensuremath{\chi}}_{c2}{(1}^{3}{P}_{2})[{\ensuremath{\chi}}_{c0}{(1}^{3}{P}_{0})].$ Our result for ${\ensuremath{\chi}}_{c2}$ is...
A hollow electron beam has been proposed as an active control tool to remove the halo from high-energy, high-current hadron or ion machines (such High-Luminosity Large Hadron Collider). To study removal rate and assess effect on core, one of two lenses in Relativistic Heavy Ion Collider was changed a Gaussian profile profile. We describe design verification parameters well methods minimize distortions, which can result emittance increase. The alignment with by using backscattered detector...
Generally, turn-to-turn power fluctuations of incoherent spontaneous synchrotron radiation in a storage ring depend on the 6D phase-space distribution electron bunch. In some cases, if only one parameter is unknown, this can be determined from measured magnitude these fluctuations. Letter, we report an absolute measurement (no free parameters or calibration) small vertical emittance (5–15 nm rms) flat beam by method, under conditions, when it unresolvable conventional light size...
An interferometric method is used to improve the accuracy of 7S-7P transition frequencies three francium isotopes by 1 order magnitude. The deduced isotope shifts for 209-211Fr confirm ISOLDE data. frequency D2 212Fr--the accepted reference all Fr shifts--is revised, and a significant difference with value found. Our results will be benchmark theory energy levels, necessary step investigate fundamental symmetries.
A method to control the diocotron instability of a hollow electron beam with periodic dipole magnetic fields has been investigated by two-dimensional particle-in-cell simulation. At first, relations between and several physical parameters such as number density, current shape beam, solenoidal field strength are theoretically analyzed without fields. Then, we study effects on using In simulation, considered applied along propagation direction temporally varying in frame. stabilizing effect is...
In a storage ring, turn-to-turn fluctuations in the intensity of spontaneous synchrotron radiation occur due to two mechanisms. The first mechanism is quantum uncertainty number emitted photons. second variations relative positions classical pointlike electrons bunch. We present unified description both effects framework optics. derive an equation for arbitrary degree coherence, which generalizes previously reported results temporally incoherent radiation. compare predictions our calculation...