C. Weidemann
A5021865418- Particle physics theoretical and experimental studies
- Nuclear physics research studies
- Atomic and Subatomic Physics Research
- Quantum Chromodynamics and Particle Interactions
- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Atomic and Molecular Physics
- Advanced NMR Techniques and Applications
- Nuclear Physics and Applications
- Magnetic confinement fusion research
- Mechanical and Optical Resonators
- Advancements in Photolithography Techniques
- Geophysical and Geoelectrical Methods
- Electron and X-Ray Spectroscopy Techniques
- Muon and positron interactions and applications
- Electron Spin Resonance Studies
- Quantum, superfluid, helium dynamics
- Superconducting Materials and Applications
- Advanced X-ray Imaging Techniques
- Advanced Electron Microscopy Techniques and Applications
- Particle Detector Development and Performance
- Advanced Data Storage Technologies
- Optical Systems and Laser Technology
- X-ray Spectroscopy and Fluorescence Analysis
- Experimental and Theoretical Physics Studies
Forschungszentrum Jülich
2011-2021
University of Ferrara
2012-2017
Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara
2014-2015
Joint Institute for Nuclear Research
2012
Tbilisi State University
2012
Petersburg Nuclear Physics Institute
2012
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
2012
Campbell Collaboration
2009
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.
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,...
This paper describes a time-marking system that enables measurement of the in-plane (horizontal) polarization 0.97-GeV/c deuteron beam circulating in Cooler Synchrotron (COSY) at Forschungszentrum J\"ulich. The clock time each polarimeter event is used to unfold 120-kHz spin precession and assign events bins according direction horizontal polarization. After accumulation for one or more seconds, down-up scattering asymmetry can be calculated matched sinusoidal function whose magnitude...
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 paper describes the commissioning of experimental equipment and machine studies required for first spin-filtering experiment with protons at a beam kinetic energy 49.3 MeV in COSY. implementation low-$\ensuremath{\beta}$ insertion made it possible to achieve lifetimes ${\ensuremath{\tau}}_{b}=8000\text{ }\text{ }\mathrm{s}$ presence dense polarized hydrogen storage-cell target areal density...
The PAX Collaboration has successfully performed a spin-filtering experiment with protons at the COSY-ring. measurement allowed determination of spin-dependent polarizing cross section, that compares well theoretical prediction from nucleon–nucleon potential. test confirms can be adopted as method to polarize stored beam and present interpretation mechanism in terms proton–proton interaction is correct. outcome utmost importance view possible application antiprotons.
New measurements are reported for the time dependence of vertical polarization a $0.97\text{ }\text{ }\mathrm{GeV}/\mathrm{c}$ deuteron beam circulating in storage ring and perturbed by an rf solenoid. The is cooler synchrotron (COSY) located at Forschungszentrum J\"ulich. was measured continuously using 1.5 cm thick carbon target edge scintillators EDDA detector. An solenoid mounted on used to generate fields near frequency $1\ensuremath{-}G\ensuremath{\gamma}$ spin resonance. Measurements...
In this paper, we demonstrate the connection between a magnetic storage ring with additional sextupole fields set so that x and y chromaticities vanish maximizing of lifetime in-plane polarization (IPP) for 0.97-GeV/c deuteron beam. The IPP magnitude was measured by continuously monitoring down-up scattering asymmetry (sensitive to sideways polarization) in an in-beam, carbon-target polarimeter unfolding precession due anomaly deuteron. optimum operating conditions long were made scanning...
A low-energy spin-physics program is being developed at the COSY storage ring. To support planned experimental activities, several tools for polarized beams and targets have been developed. The paper presents physics case readiness of setup its realization.
We propose to use an internal polarized hydrogen storage cell gas target in the AD ring determine for first time two total spin-dependent pbar-p cross sections sigma_1 and sigma_2 at antiproton beam energies range from 50 450 MeV. The data obtained are of interest by themselves general theory interactions since they will provide a experimental constraint spin-spin dependence nucleon-antinucleon potential energy interest. In addition, measurements polarization buildup stored antiprotons...
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...
We investigated coherent betatron oscillations of a deuteron beam in the storage ring cooler synchrotron and ring, excited by detuned rf Wien filter (WF). The were detected conventional position monitors. With currently available apparatus, we show that oscillation amplitudes down to $1\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ can be detected. interpretation response stored WF is based on simulations evolution lattice realistic time-dependent 3D field maps WF. Future measurements electric...
The transverse spin correlations ${A}_{x,x}$ and ${A}_{y,y}$ have been measured in the $\stackrel{P\vec}{d}\stackrel{P\vec}{p}\ensuremath{\rightarrow}{p}_{\text{spec}}{{pp}}_{s}{\ensuremath{\pi}}^{\ensuremath{-}}$ reaction at COSY-ANKE 353 MeV per nucleon. Here ${{pp}}_{s}$ denotes a proton-proton pair with low excitation energy, which is dominantly ${}^{1}{S}_{0}$ state. By measuring three protons final state it was possible to extract events where there spectator proton ${p}_{\text{spec}}$...
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 vector and tensor analysing powers, Ay Ayy, of the pd→→n{pp}s charge-exchange reaction have been measured at a beam energy 600 MeV COSY-ANKE facility by using an unpolarised proton incident on internal storage cell target filled with polarised deuterium gas. low recoiling protons were in pair silicon tracking telescopes placed either side target. Putting cut 3 diproton excitation ensured that two dominantly S01 state, here denoted {pp}s. polarisation gas was established through...
Studying and understanding social networks is crucial for accurately defining ideological polarization, since they enable precise modeling of structures. One the limitations many methods quantifying polarization on assumption a two-dimensional opinion space. This prevents accurate study multipolar systems like multi-party political systems, where more than two poles beneficial. Here, I experimentally compare network, find that average pairwise distance extension generalized Euclidean...
The charge exchange of vector polarised deuterons on a hydrogen target has been studied in high statistics experiment at the COSY-ANKE facility deuteron beam energy Td=726MeV. By selecting two fast protons low relative Epp, measured analysing powers and spin correlations are sensitive to interference terms between specific neutron–proton charge-exchange amplitudes neutron kinetic Tn≈12Td=363MeV. An impulse approximation calculation, which takes into account corrections due angular...