A5060883902- Particle accelerators and beam dynamics
- Particle Accelerators and Free-Electron Lasers
- Laser-Plasma Interactions and Diagnostics
- Atomic and Molecular Physics
- Planetary Science and Exploration
- Magnetic confinement fusion research
- Space Exploration and Technology
- Plasma Diagnostics and Applications
- Particle physics theoretical and experimental studies
- Diamond and Carbon-based Materials Research
- Laser-induced spectroscopy and plasma
- Nuclear physics research studies
- Neutrino Physics Research
- Military Defense Systems Analysis
- Aerospace and Aviation Technology
- Nonlinear Optical Materials Studies
- Calibration and Measurement Techniques
- Semiconductor materials and devices
- Laser Material Processing Techniques
- Spaceflight effects on biology
- Astronomical and nuclear sciences
- Human-Automation Interaction and Safety
- Fusion materials and technologies
- Nuclear reactor physics and engineering
- Particle Detector Development and Performance
Leipzig University
2023-2024
Deutsches Elektronen-Synchrotron DESY
2016-2020
University of North Carolina at Chapel Hill
1999-2017
University of California, Berkeley
2005
Beta-decay rates for spherical neutron-rich r-process waiting-point nuclei are calculated within a fully self-consistent Quasiparticle Random-Phase Approximation, formulated in the Hartree-Fock-Bogolyubov canonical single-particle basis. The same Skyrme force is used everywhere calculation except proton-neutron particle-particle channel, where finite-range consistently employed. In all but heaviest nuclei, resulting half-lives usually shorter by factors of 2 to 5 than those calculations that...
Particle-beam-driven plasma wakefield acceleration (PWFA) enables various novel high-gradient techniques for powering future compact light-source and high-energy physics applications. Here, a driving particle bunch excites response in medium, which may rapidly accelerate trailing witness beam. In this Letter, we present the measurement of ratios to deceleration driver bunch, so-called transformer ratio, significantly exceeding fundamental theoretical thus far experimental limit 2 PWFA. An...
We present a new technique for inferring neutral densities in the Martian upper atmosphere from atmospheric absorption of magnetically reflected solar wind electrons. Using electron loss cone measurements Magnetometer/Electron Reflectometer (MAG/ER) experiment on board Mars Global Surveyor (MGS), we derive thermospheric (∼160–230 km altitude) southern hemisphere 160° to 200°E at 2am local time, continuously 1999 2005. find mean density 0.027 kg/km 3 160 and observe latitude‐dependent,...
Self-modulation of an electron beam in a plasma has been observed. The propagation long (several wavelengths) bunch overdense resulted the production multiple bunches via self-modulation instability. Using combination radio-frequency deflector and dipole spectrometer, time energy structure self-modulated was measured. longitudinal phase space measurement showed modulation into three with approximately $200\text{ }\text{ }\mathrm{keV}/c$ amplitude momentum modulation. Demonstrating this...
Background: The interacting boson model has been used extensively to calculate the matrix elements governing neutrinoless double-$\ensuremath{\beta}$ decay. Studies within other models---the shell model, quasiparticle random-phase approximation, and nuclear energy-density functional theory---indicate that a good description of neutron-proton pairing is essential for accurate calculations those elements, even though isotopes in experiment have significantly more neutrons than protons. usual...
A common technique for color center creation in wideband gap semiconductors employs ion implantation and a subsequent thermal annealing. In general, this annealing process is conducted an vacuum oven. Here, we exploit the based on femtosecond laser pulses. For that purpose, implant fluorine ions at 54 keV chlorine 74 diamond perform micrometer precise using focused pulses 800 ± (30) nm with different pulse numbers repetition rates. way, were able to create shallow spots centers of varying brightness.
In this study, we investigated the creation of mono crystalline diamond membranes for use in two-dimensional optical cavities. The method involves ion irradiation to create a buried layer damaged material that is removed leave free-standing top layer. Simulations were used determine optimal parameters irradiation, which tested experiments. Hydrogen ions found be species and long-term high-temperature annealing was beneficial reducing ion-induced damage membrane. resulting membranes, 300 nm...
In the field of beam driven acceleration particles in plasma wakefields (PWFA), source medium is a crucial part accelerator setup. Gas discharges have proven to be reliable and simple type past experiments. Nevertheless, especially cells that aim for peak density range 1015 cm−3, physical apertures around 10 mm, lengths up several meters, stability discharge ignition pulse current waveform limiting applicability. We show successful mitigation these jitters 0.1 m argon gas cell, operating at...
Various applications in modern particle accelerators or experiments involving high energy beams require a gas atmosphere involve the production of big amounts residual gas. Among these are, e.g., cells for plasma acceleration, jet targets, lenses. As beam quality and stable operation RF-accelerator cavities demand ultra-high vacuum (UHV) conditions, separation between pressure UHV beamline sections is needed. Commonly, this realized by differential pumping thin windows, main advantages...
The self-modulation instability is fundamental for the plasma wakefield acceleration experiment of AWAKE (Advanced Wakefield Experiment) collaboration at CERN where this effect used to generate proton bunches resonant excitation high fields. Utilizing availability flexible electron beam shaping together with excellent diagnostics including an RF deflector, a supporting was set up accelerator PITZ (Photo Injector Test facility DESY, Zeuthen site), given that underlying physics same. After...
7th International Particle Accelerator Conference, Busan, Korea, 8 May 2016 - 13 ; (2016).