R. Stassen
A5021574966- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Particle physics theoretical and experimental studies
- Atomic and Subatomic Physics Research
- Magnetic confinement fusion research
- Quantum Chromodynamics and Particle Interactions
- Nuclear physics research studies
- Gyrotron and Vacuum Electronics Research
- Particle Detector Development and Performance
- High-Energy Particle Collisions Research
- Nuclear Physics and Applications
- Advanced NMR Techniques and Applications
- Nuclear reactor physics and engineering
- X-ray Spectroscopy and Fluorescence Analysis
- Dark Matter and Cosmic Phenomena
- Atomic and Molecular Physics
- Heat Transfer and Optimization
- Computational Physics and Python Applications
- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Spacecraft and Cryogenic Technologies
- Advanced X-ray Imaging Techniques
- Geophysical and Geoelectrical Methods
- Pulsed Power Technology Applications
Forschungszentrum Jülich
2010-2024
Petersburg Nuclear Physics Institute
2016
Stadtwerke Jülich (Germany)
2006
We report on an exclusive and kinematically complete high-statistics measurement of the basic double-pionic fusion reaction pn→dπ(0)π(0) over full energy region ABC effect, a pronounced low-mass enhancement in ππ-invariant mass spectrum. The measurements, which cover also transition to conventional t-channel ΔΔ process, were performed with upgraded WASA detector setup at COSY. data reveal Abashian-Booth-Crowe effect be uniquely correlated Lorentzian dependence integral cross section....
A new method to determine the spin tune is described and tested. In an ideal planar magnetic ring, tune-defined as number of precessions per turn-is given by ν(s)=γG (γ Lorentz factor, G gyromagnetic anomaly). At 970 MeV/c, deuteron spins coherently precess at a frequency ≈120 kHz in Cooler Synchrotron COSY. The deduced from up-down asymmetry deuteron-carbon scattering. time interval 2.6 s, was determined with precision order 10^{-8}, 1×10^{-10} for continuous 100 s accelerator cycle. This...
We observe a deuteron beam polarization lifetime near 1000 s in the horizontal plane of magnetic storage ring (COSY). This long spin coherence time is maintained through combination bunching, electron cooling, sextupole field corrections, and suppression collective effects current limits. record required for search an intrinsic electric dipole moment on at statistical sensitivity level approaching 10^{-29} e cm.
Based on the notion that local dark-matter field of axions or axionlike particles (ALPs) in our Galaxy induces oscillating couplings to spins nucleons and nuclei (via electric dipole moment latter and/or paramagnetic axion-wind effect), we establish feasibility a new method search for ALPs storage rings. previous work allows us maintain in-plane polarization stored deuteron beam few hundred seconds, perform first proof-of-principle experiment at Cooler Synchrotron (COSY) scan momenta near...
This paper presents the successful application of a phase-lock feedback system to maintain resonance condition radio frequency (rf) spin rotator (specifically, an rf Wien filter) with respect 120 kHz precession in Cooler Synchrotron (COSY) storage ring. Real-time monitoring and filter signal allows relative phase between two be stabilized at arbitrary setpoint. The compensates for deviations by adjusting and/or as needed. With this method, variation demand standard deviation...
This Letter reports the successful use of feedback from a spin polarization measurement to revolution frequency $0.97\text{ }\text{ }\mathrm{GeV}/c$ bunched and polarized deuteron beam in Cooler Synchrotron (COSY) storage ring order control both precession rate ($\ensuremath{\approx}121\text{ }\mathrm{kHz}$) phase horizontal component. Real time synchronization with radio (rf) solenoid made possible rotation out plane, yielding demonstration method manipulate polarization. In particular,...
The stable spin direction of polarized particles in a storage ring was determined first experimentally, through an accurate measurement the tune and its response to longitudinal magnetic fields.
The proposed method exploits charged particles confined as a storage ring beam (proton, deuteron, possibly $^3$He) to search for an intrinsic electric dipole moment (EDM) aligned along the particle spin axis. Statistical sensitivities could approach 10$^{-29}$ e$\cdot$cm. challenge will be reduce systematic errors similar levels. adjusted preserve polarisation, initially parallel velocity, times in excess of 15 minutes. Large radial fields, acting through EDM, rotate polarisation from...
The repeated passage of a coasting ion beam storage ring through thin target induces shift in the revolution frequency due to energy loss target. Since is proportional beam-target overlap, its measurement offers possibility determining thickness and hence corresponding luminosity an experiment. This effect has been investigated with internal proton 2.65 GeV at COSY-J\"ulich accelerator using ANKE spectrometer hydrogen cluster-jet Possible sources error, especially those arising from...
The proton analysing power in $\vec{p}p$ elastic scattering has been measured at small angles COSY-ANKE 796 MeV and five other beam energies between 1.6 2.4 GeV using a polarised beam. asymmetries obtained by detecting the fast ANKE forward detector or slow recoil silicon tracking telescope are completely consistent. Although results agree well with many published data MeV, also most recent partial wave solution this energy, higher lie above predictions of angles. An updated phase shift...
In order to measure the mass of $\ensuremath{\eta}$ meson with high accuracy using $dp\ensuremath{\rightarrow}^{3}\mathrm{He}\ensuremath{\eta}$ reaction, momentum circulating deuteron beam in Cooler Synchrotron COSY Forschungszentrum J\"ulich has be determined unprecedented precision. This been achieved by studying spin dynamics polarized beam. By depolarizing through use an artificially induced resonance, it was possible evaluate its $p$ a precision...
The differential cross section for proton-proton elastic scattering has been measured at a beam energy of 1.0 GeV and in 200 MeV steps from 1.6 to 2.8 centre-of-mass angles the range 12-16 degrees 25-30 degrees, depending on energy. Absolute normalisations typically 3% were achieved by studying losses circulating COSY storage ring as it passed repeatedly through windowless hydrogen target ANKE magnetic spectrometer. It is shown that data have significant impact upon partial wave analysis....
This paper reports the first simultaneous measurement of horizontal and vertical components polarization vector in a storage ring under influence radio frequency (rf) solenoid. The experiments were performed at Cooler Synchrotron COSY J\"ulich using polarized, bunched $0.97\,\textrm{GeV/c}$ deuteron beam. Using new spin feedback system, we set initial phase difference between solenoid field precession to predefined value. system was then switched off, allowing change over time, on rotate...
The high-energy storage ring (HESR) of the international facility for antiproton and ion research (FAIR) at GSI in Darmstadt is dedicated to strong interaction studies with antiprotons momentum range from 1.5 15 GeV/c. Powerful phase-space cooling needed reach demanding experimental requirements terms luminosity beam quality. Status details technical planning including cryogenic concept will be presented.
Abstract A measurement of vector analyzing powers in elastic deuteron-carbon scattering has been performed at the Cooler Synchrotron COSY Forschungszentrum Jülich, Germany. Seven kinetic beam energies between 170 and 380 MeV have used. vector-polarized from a polarized deuteron source was injected, accelerated to final desired energy stored COSY. thin needle-shaped diamond strip used as carbon target, onto which slowly steered. Elastically scattered deuterons were identified forward...
This project exploits charged particles confined as a storage ring beam (proton, deuteron, possibly $^3$He) to search for an intrinsic electric dipole moment (EDM, $\vec d$) aligned along the particle spin axis. Statistical sensitivities can approach $10^{-29}$~e$\cdot$cm. The challenge will be reduce systematic errors similar levels. adjusted preserve polarization, initially parallel velocity, times in excess of 15 minutes. Large radial fields, acting through EDM, rotate polarization ($\vec...
The low level rf system for the superconducting Darmstadt electron linear accelerator (S-DALINAC) developed 20 years ago and operating since converts 3 GHz signals from cavities down to baseband not an intermediate frequency. While designing new, digital control this concept was kept: module does $I/Q$ amplitude modulation/demodulation while frequency board, housing field programmable gate array analyzes processes signals. Recently, flexibility of realized: By replacing...
The superconducting injector linac COSY-SCL is being designed and constructed at the Forschungszentrum Juelich. train goal of new to fill cooler synchrotron COSY with polarized protons as well deuterons up space-charge limit injection energy. characterized by a base frequency 160 MHz, 25 kV ion-source extraction voltage, pulse length 500 /spl mu/s, maximum repetition rate 2 Hz, into beta/=0.073 kinetic energies 52 MeV for 56 deuterons, respectively. configuration presented, its main...
In the Modularized Start Version of Facility Antiproton and Ion Research (FAIR) at Darmstadt Germany, 3 GeV antiprotons are precooled in collector ring accumulated high energy storage (HESR). They further accelerated to 14 or decelerated 1 for experiments with a high-density internal target. The powerful beam cooling devices, stochastic electron will support provision high-resolution antiproton beam. other option FAIR is prepare low energy, 300 keV connecting existing rings ESR CRYRING HESR....