D. Grzonka
A5066881251- Particle physics theoretical and experimental studies
- Atomic and Molecular Physics
- Quantum Chromodynamics and Particle Interactions
- Atomic and Subatomic Physics Research
- Particle Accelerators and Free-Electron Lasers
- High-Energy Particle Collisions Research
- Particle accelerators and beam dynamics
- Nuclear physics research studies
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Cold Atom Physics and Bose-Einstein Condensates
- Superconducting Materials and Applications
- Muon and positron interactions and applications
- Radiation Detection and Scintillator Technologies
- Magnetic confinement fusion research
- Quantum, superfluid, helium dynamics
- X-ray Spectroscopy and Fluorescence Analysis
- Mass Spectrometry Techniques and Applications
- Advanced NMR Techniques and Applications
- Advanced Chemical Physics Studies
- Nuclear Physics and Applications
- Computational Physics and Python Applications
- Magnetic properties of thin films
- Spacecraft and Cryogenic Technologies
- Ion-surface interactions and analysis
Forschungszentrum Jülich
2015-2024
Ruhr University Bochum
2018
Jülich Aachen Research Alliance
2018
Ernst Ruska Centre
2005-2011
York University
2008
Stadtwerke Jülich (Germany)
1995
Antihydrogen atoms (H¯) are confined in an Ioffe trap for 15-1000 s-long enough to ensure that they reach their ground state. Though reproducibility challenges remain making large numbers of cold antiprotons (p¯) and positrons (e(+)) interact, 5±1 simultaneously ground-state produced observed on average, substantially more than previously reported. Increases the number trapped H¯ critical if laser cooling is be demonstrated spectroscopic studies at interesting levels precision carried out.
Slow antihydrogen ($\overline{\mathrm{H}}$) is produced within a Penning trap that located quadrupole Ioffe trap, the latter intended to ultimately confine extremely cold, ground-state $\overline{\mathrm{H}}$ atoms. Observed atoms in this configuration resolve debate about whether positrons and antiprotons can be brought together form divergent magnetic fields of trap. The number detected actually increases when 400 mK turned on.
For the first time a single trapped antiproton (p) is used to measure p magnetic moment μ(p). The μ(p)=μ(p)S/(ℏ/2) given in terms of its spin S and nuclear magneton (μ(N)) by μ(p)/μ(N)=-2.792 845±0.000 012. 4.4 parts per million (ppm) uncertainty 680 times smaller than previously realized. Comparing proton measured using same method trap electrodes gives μ(p)/μ(p)=-1.000 000±0.000 005 5 ppm, for μ(p)=μ(p)S/(ℏ/2), consistent with prediction CPT theorem.
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.
Taking advantage of both the high mass resolution COSY-11 detector and energy low-emittance proton beam cooler synchrotron COSY, we determine excitation function for pp→ppη(') reaction close to threshold. Combining these data with previous results, extract scattering length η(')-proton potential in free space be Re(a(pη(')))=0±0.43 fm Im(a(pη(')))=0.37(-0.16)(+0.40) fm.
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...
Adiabatic cooling is shown to be a simple and effective method cool many charged particles in trap very low temperatures. Up $3\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $\overline{p}$ are cooled 3.5 K---${10}^{3}$ times more cold 3 lower temperature than previously reported. A second cools plasmas via the synchrotron radiation of embedded ${e}^{\ensuremath{-}}$ (with fewer $\overline{p}$) preparation for adiabatic cooling. No lost during either process---a significant advantage rare particles.
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.
Four billion positrons (e+) are accumulated in a Penning–Ioffe trap apparatus at 1.2 K and <6 × 10−17 Torr. This is the largest number of ever held Penning trap. The e+ cooled by collisions with trapped electrons (e−) this first demonstration using e− for efficient loading into combined low temperature vacuum pressure provide an environment suitable antihydrogen () production, long antimatter storage times, sufficient high-precision tests gravity CPT.
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...
A feasibility study has been performed in order to investigate the performance of HADES detector measure electromagnetic decays hyperon resonances $\Sigma(1385)^0$, $\Lambda(1405)$ and $\Lambda{\Lambda}(1520)$ as well production double strange baryon systems $\Xi^-$ $\Lambda\Lambda$ p+p reactions at a beam kinetic energy 4.5 GeV. The existing will be upgraded by new Forward Detector, which extends acceptance into range polar angles that plays crucial role for these investigations. analysis...
Antiprotons (p¯) remain confined in a Penning trap, sufficient numbers to form antihydrogen (H¯) atoms via charge exchange, when the radial field of quadrupole Ioffe trap is added. This first demonstration with p¯ suggests that traps can be superimposed upon and e+ attempt capture H¯ as they form, contrary conclusions previous analyses.Received 19 December 2006DOI:https://doi.org/10.1103/PhysRevLett.98.113002©2007 American Physical Society
Taking advantage of both the low-emittance proton-beam Cooler Synchrotron COSY and high momentum precision COSY-11 detector system, mass distribution eta' meson was measured with a resolution 0.33 MeV/c^2 (FWHM), improving experimental by almost an order magnitude respect to previous results. Based on sample more than 2300 reconstructed pp --> events total width determined be 0.226 +- 0.017(stat.) 0.014(syst.) MeV/c^2.
We present the first determination of energy-dependent amplitudes N⁎ resonances extracted from their decay in KΛ pairs p+p→pK+Λ reactions. A combined Partial Wave Analysis seven data samples with exclusively reconstructed events measured by COSY-TOF, DISTO, FOPI and HADES Collaborations fixed target experiments at kinetic energies between 2.14 to 3.5 GeV is used determine amplitude resonant non-resonant contributions into associated strangeness final state. The contribution masses 1650...
We present a Lyman-α laser developed for cooling trapped antihydrogen. The system is based on pulsed Ti:sapphire operating at 729 nm that frequency doubled using an LBO crystal and then tripled in Kr/Ar gas cell. After conversion, this produces up to 5.7 μW of average power the wavelength. This part ATRAP experiment antiproton decelerator CERN.
Lasers are used to control the production of highly excited positronium atoms (Ps*). The laser light excites Cs Rydberg states that have a large cross section for resonant charge-exchange collisions with cold trapped positrons. For each trial 30 million positrons, more than 700 000 created Ps* trajectories near axis apparatus, and detected using Stark ionization. This number is 500 times higher realized in an earlier proof-of-principle demonstration (2004 Phys. Lett. B 597 257). A second...