A5066258291- 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 X-ray Imaging Techniques
- Nuclear physics research studies
- Laser Design and Applications
- Nuclear Physics and Applications
- Particle physics theoretical and experimental studies
- Magnetic confinement fusion research
- Photonic and Optical Devices
- Advancements in Photolithography Techniques
- X-ray Spectroscopy and Fluorescence Analysis
- Quantum Chromodynamics and Particle Interactions
- Electron and X-Ray Spectroscopy Techniques
- Advanced NMR Techniques and Applications
- Atomic and Molecular Physics
- Radiation Detection and Scintillator Technologies
- High-Energy Particle Collisions Research
- Silicon and Solar Cell Technologies
- Pulsed Power Technology Applications
- Crystallography and Radiation Phenomena
- Laser-Plasma Interactions and Diagnostics
Brookhaven National Laboratory
2014-2024
Stony Brook University
2023
Argonne National Laboratory
2015
Duke University
1998-2009
RIKEN BNL Research Center
2006-2007
Triangle Universities Nuclear Laboratory
2004
Budker Institute of Nuclear Physics
1993-2002
Russian Academy of Sciences
1989-1995
A nearly monochromatic beam of 100% linearly polarized γ rays has been produced via Compton backscattering inside a free electron laser optical cavity. The 12.2 MeV was obtained by 379.4 nm free-electron photons from 500 electrons circulating in storage ring. detailed description the γ-ray and outlook for future improvements are presented.Received 24 February 1997DOI:https://doi.org/10.1103/PhysRevLett.78.4569©1997 American Physical Society
The quality and intensity of gamma rays at the High Intensity gamma-ray Source are shown to make nuclear resonance fluorescence studies possible a new level precision efficiency. First experiments have been carried out using an intense (10(7) gamma/s) beam 100% linearly polarized, nearly monoenergetic, on semimagic nucleus (138)Ba. Negative parity quantum numbers assigned 18 dipole excitations (138)Ba between 5.5 MeV 6.5 from azimuthal gamma-intensity asymmetries.
This document presents BNL's plan for an electron-ion collider, eRHIC, a major new research tool that builds on the existing RHIC facility to advance long-term vision Nuclear Physics discover and understand emergent phenomena of Quantum Chromodynamics (QCD), fundamental theory strong interaction binds atomic nucleus. We describe scientific requirements such facility, following up community-wide 2012 white paper, 'Electron-Ion Collider: Next QCD Frontier', present design concept incorporates...
Continuous-wave photoinjectors operating at high accelerating gradients promise to revolutionize many areas of science and applications. They can establish the basis for a new generation monochromatic x-ray free electron lasers, high-brightness hadron beams, or microchip production. In this Letter we report on record-performing superconducting rf gun with ${\mathrm{CsK}}_{2}\mathrm{Sb}$ photocathode. The is generating charge bunches (up $10\text{ }\text{ }\mathrm{nC}/\text{bunch}$) low...
Abstract High brightness, high charge electron beams are critical for a number of advanced accelerator applications. The initial emittance the beam, which is determined by mean transverse energy (MTE) and laser spot size, one most important parameters determining beam quality. bialkali photocathodes illuminated visible have advantages quantum efficiency (QE) low MTE. Furthermore, Superconducting Radio Frequency (SRF) guns can operate in continuous wave (CW) mode at accelerating gradients,...
Cooling of beams gold ions using electron bunches accelerated with radio-frequency systems was recently experimentally demonstrated in the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. Such an approach is new and opens possibility this technique higher energies than possible electrostatic acceleration beams. The challenges include generation suitable for cooling, delivery required quality to cooling sections without degradation beam angular divergence energy spread,...
We report first results from our effort to couple a high resolution photoemission electron microscope (PEEM) the OK-4 ultraviolet free laser at Duke University (OK-4/Duke UV FEL). The OK-4/Duke FEL is intensity source of tunable monochromatic photons in 3–10 eV energy range. This tunability unique and allows us operate near threshold any samples thus maximize sample contrast while keeping chromatic berrations PEEM minimal. have recorded images variety using spontaneous radiation OK-4/ photon...
The first measurement of the ${}^{2}\mathrm{H}(\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\gamma}},n)p$ analyzing power near threshold has been performed using High-Intensity Gamma-ray Source (HIGS) at Duke Free-Electron Laser Laboratory. A 3.58 MeV $\ensuremath{\gamma}$-ray beam having an energy resolution $2.5%$ and $100%$ linear polarization was incident on active ${\mathrm{C}}_{6}{\mathrm{D}}_{12}$ target. Outgoing neutrons were detected parallel perpendicular to plane a lab angle...
The photon analyzing power for the photodisintegration of deuteron was measured seven gamma-ray energies between 2.39 and 4.05 MeV using linearly polarized beam high-intensity source at Duke Free-Electron Laser Laboratory. data provide a stringent test theoretical calculations inverse reaction, neutron–proton radiative capture reaction important Big-Bang nucleosynthesis. Our are in excellent agreement with potential model effective field theory calculations. Therefore, uncertainty baryon...
Parity quantum numbers for dipole-excited states of the nuclei $^{92}\mathrm{Zr}$ and $^{96}\mathrm{Mo}$ have been determined from azimuthal asymmetries nuclear resonance fluorescence intensities induced with linearly polarized photon beam $\mathrm{HI}\ensuremath{\gamma}\mathrm{S}$ facility at Duke University. This parity information is crucial an interpretation investigated $J=1$ as two-phonon excitations originating inhomogeneous phonon coupling.
The Pb(γ→,γ′) photon scattering reaction has been studied with the nearly monochromatic, linearly polarized beams at High Intensity γ-ray Source (HIγS) DFELL. Azimuthal intensity asymmetries measured respect to polarization plane of beam have used for first time assign both spin and parity quantum numbers dipole excited states 206,207,208Pb excitation energies in vicinity 5.5 MeV. Evidence dominant particle–core coupling is deduced from these results along information on electromagnetic...
The 100% polarized photon beam at the high intensity $\ensuremath{\gamma}$ ray source $(\text{HI}\ensuremath{\gamma}\text{S})$ Duke University has been used to determine parity of six dipole excitations between 2.9 and 3.6 MeV in deformed nuclei $^{172,174}\mathrm{Yb}$ scattering $(\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\gamma}},{\ensuremath{\gamma}}^{'})$ experiments. measured parities are compared with previous assignments based on K quantum number that had assigned nuclear...
Coherent radiation from a relativistic electron beam is valuable way to overcome the present limitations of conventional lasers and synchrotron light sources. The typical scheme has electrons, directly linac, in single-pass interaction with laser pulse presence static undulator magnetic field. We demonstrate that storage-ring free-electron can also achieve harmonic generation (down 36.5 nm), presenting both experimental theoretical results, offer reliable interpretation peculiar underlying...
The linearly polarized \ensuremath{\gamma}-ray beam produced by the $\mathrm{HI}\ensuremath{\gamma}\mathrm{S}$ facility has been used to determine parity of two previously known dipole excitations in ${}^{88}\mathrm{Sr}.$ azimuthal asymmetry \ensuremath{\gamma} rays process nuclear resonance fluorescence indicated that state at 4.742 MeV, recently discussed as a new form $M1$ excitation, is fact ${1}^{\ensuremath{-}}$ $(E1)$ state. MeV must, therefore, be reconsidered...
A high-current high-brightness electron accelerator for low-energy RHIC cooling (LEReC) was successfully commissioned at Brookhaven National Laboratory. The LEReC includes a dc photoemission gun, laser system, photocathode delivery magnets, beam diagnostics, superconducting rf booster cavity, and set of normal conducting cavities to provide enough flexibility tune the in longitudinal phase space. Cooling with nonmagnetized accelerated beams requires corrections obtain small momentum spread...
Since 1979, experiments on the storage ring VEPP-3 with an optical klystron (OK) have been performed at INP Academy of Sciences USSR. In 1981, and 1983, three different OK magnetic systems based SmCo permanent magnets undulators were installed straight section 6300-A wavelength. The following gains per pass obtained: 0.5% in 1980, 1% 1982, 2%–2.5% 1984. late 1985, we decided to improve develop a dc bypass, special dedicated for operation. bypass allowed us install system 7.8 m length...