A5078721826- Atomic and Subatomic Physics Research
- Quantum, superfluid, helium dynamics
- Advanced NMR Techniques and Applications
- Nuclear Physics and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Advanced MRI Techniques and Applications
- Dark Matter and Cosmic Phenomena
- Physics of Superconductivity and Magnetism
- Nuclear physics research studies
- Particle physics theoretical and experimental studies
- Radiation Detection and Scintillator Technologies
- Neutrino Physics Research
- Noncommutative and Quantum Gravity Theories
- Radioactive Decay and Measurement Techniques
- NMR spectroscopy and applications
- Quantum Chromodynamics and Particle Interactions
- Superconducting Materials and Applications
- Advanced Chemical Physics Studies
- Atomic and Molecular Physics
- Advanced Frequency and Time Standards
- Clinical Laboratory Practices and Quality Control
- Black Holes and Theoretical Physics
- Scientific Measurement and Uncertainty Evaluation
- Electron and X-Ray Spectroscopy Techniques
- Geophysics and Sensor Technology
Johannes Gutenberg University Mainz
2013-2024
Schrodinger (United States)
2013
University of Applied Sciences Mainz
2013
DKFZ-ZMBH Alliance
2006
German Cancer Research Center
2006
Olympus (United States)
2002
Institut Laue-Langevin
1997-2000
Old Dominion University
1998
University of Basel
1998
Institut Langevin
1998
We present the result of an experiment to measure electric dipole moment (EDM) neutron at Paul Scherrer Institute using Ramsey's method separated oscillating magnetic fields with ultracold neutrons (UCN). Our measurement stands in long history EDM experiments probing physics violating time reversal invariance. The salient features this were use a Hg-199 co-magnetometer and array optically pumped cesium vapor magnetometers cancel correct for field changes. statistical analysis was performed...
To assess the feasibility of helium-3 magnetic resonance (MR) imaging with a three-dimensional fast low-angle shot (FLASH) sequence, He-3 gas (volume, 300 mL; pressure, 3 x 10(5) Pa; polarized up to 45% by means optimal pumping) was inhaled five healthy volunteers and patients pulmonary diseases. All breath-hold examinations (22-42 seconds) were completed successfully. Normal ventilation depicted homogeneous high signal intensity, lesions as causing defects, obstructive lung disease severely...
Abstract The purpose of this study was to describe the 3He MRI findings normal pulmonary ventilation in healthy volunteers and evaluate abnormalities patients with different lung diseases. Hyperpolarized gas (300 ml, 3 × 10 5 Pa, polarized 35–45% by optical pumping, provided special glass cells) inhaled 8 Imaging performed a three‐dimensional fast low‐angle shot (FLASH) sequence (TR = 11.8 msec; TE transmitter amplitude, 5–8 V; corresponding flip angle, <5°) single breath‐hold (22–42...
We report on the search for a CPT- and Lorentz-invariance-violating coupling of He3 Xe129 nuclear spins (each largely determined by valence neutron) to posited background tensor fields that permeate Universe. Our experimental approach is measure free precession spin polarized atoms in homogeneous magnetic guiding field about 400 nT using LTC SQUIDs as low-noise flux detectors. As laboratory reference frame rotates with respect distant stars, we look sidereal modulation Larmor frequencies...
We search for a spin-dependent $P$- and $T$-violating nucleon-nucleon interaction mediated by light pseudoscalar bosons such as axions or axionlike particles. employ an ultrasensitive low-field magnetometer based on the detection of free precession colocated $^{3}\mathrm{He}$ $^{129}\mathrm{Xe}$ nuclear spins using SQUIDs low-noise magnetic flux detectors. The frequency shift in presence unpolarized mass was measured to determine coupling particles spin bound neutron. For boson masses...
The electric form factor of the neutron ${G}_{E,n}$ has been measured in quasifree ${}^{2}\mathrm{H}(\stackrel{\ensuremath{\rightarrow}}{e}{,e}^{\ensuremath{'}}\stackrel{\ensuremath{\rightarrow}}{n})p$ reaction using 855 MeV polarized cw electron beam Mainz Microtron MAMI. polarization scattered neutrons was analyzed a polarimeter consisting two walls plastic scintillators. precession spin magnetic field used for first time to circumvent measurement effective analyzing power and...
We have measured the neutron electric form factor Gen via 3He→(e→,e′n)pp at Q2=0.67(GeV/c)2 using 3-spectrometer facility of A1 Collaboration Mainz Microtron and a dedicated detector. High pressure polarized 3He→ gas was used as target neutrons. is determined from ratio asymmetries A⊥/A∥ in quasifree kinematics with spin perpendicular parallel to momentum transfer. find Gen=0.052±0.011±0.005.Received 30 April 1999DOI:https://doi.org/10.1103/PhysRevLett.83.4257©1999 American Physical Society
Abstract The nuclear spin polarization of noble gases can be enhanced strongly by laser optical pumping followed electron‐nuclear transfer. Direct metastable 3 He atoms has been shown to produce enormous on the order 0.4–0.6. This is about 10 5 times larger than water protons at thermal equilibrium used in conventional MRI. We demonstrate that hyper‐polarized gas applied magnetic resonance imaging organs with air‐filled spaces humans. In vivo MR experiments were performed a whole‐body...
Theories are developed to evaluate Larmor frequency shifts, derived from geometric phases, in experiments measure electric dipole moments (EDM's) of trapped, atoms, molecules, and neutrons. A part these shifts is proportional the applied field can be interpreted falsely as an moment. comparison made between our theoretical predictions for some results recent experiments, which shows agreement within experimental errors 15%. The also demonstrates that trapped particle EDM have reached a...
On the basis of revisions some systematic errors, we reanalyzed electron-antineutrino angular correlation ($a$ coefficient) in free neutron decay inferred from recoil energy spectrum protons which are detected $4\ensuremath{\pi}$ by aSPECT spectrometer. With $a=\ensuremath{-}0.104\text{ }02(82)$ new value differs only marginally one published 2020. The experiment also has sensitivity to $b$, Fierz interference term. From a correlated $(b,a)$ fit proton spectrum, derive limit...
We report on compact, gaseous 3He NMR probes for precision magnetometry of magnetic fields B > 0.1 T in the temperature range from ambient temperatures down to 4 Kelvin. The gas is polarized at thermal equilibrium under pressures up 100 bar provide a high nuclear spin density. In order achieve sensor readout rates (Hz), paramagnetic substances and/or silica gel with specific surface area were added reduce otherwise long T1 relaxation time pure reach polarization equilibrium. Sensitivity...
The charge form factor of the neutron has been determined from asymmetries measured in quasi--elastic pol.3He(pol e,e'n) at a momentum transfer 0.67(GeV/c)^2. In addition, target analyzing power, A_y^o, to study effects final state interactions and meson exchange currents.
Inhalation of hyperpolarized 3 He allows magnetic resonance imaging (MRI) ventilated airspaces. hyperpolarization decays more rapidly when interacting with paramagnetic O 2 . We describe a method for in vivo determination intrapulmonary concentrations ([O ]) based on MRI analysis the fate measured amounts inhaled imaged regions lung. Anesthetized pigs underwent controlled normoventilation 1.5-T unit. The inspired fraction was varied to achieve different end-tidal [O ] fractions ([Formula:...
A clock comparison experiment, analyzing the ratio of spin precession frequencies stored ultracold neutrons and 199Hg atoms, is reported. No daily variation this could be found, from which set an upper limit on Lorentz invariance violating cosmic anisotropy field b perpendicular < 2 x 10(-20) eV (95% C.L.). This first for free neutron. result also interpreted as a direct gravitational dipole moment neutron |gn| 0.3 eV/c2 m spin-dependent interaction with Sun. Analyzing Earth, based previous...
We report on a measurement of the $CP$-violating permanent electric dipole moment (EDM) neutral $^{129}\mathrm{Xe}$ atom. Our experimental approach is based detection free precession co-located nuclear spin-polarized $^{3}\mathrm{He}$ and samples. The EDM sensitivity benefits strongly from long spin coherence times several hours achieved in diluted gases homogeneous weak magnetic fields about 400 nT. A finite indicated by change frequency, as an field periodically reversed with respect to...
We report on a precise measurement of the electron-antineutrino angular correlation ($a$ coefficient) in free neutron beta-decay from $a$SPECT experiment. The $a$ coefficient is inferred recoil energy spectrum protons which are detected 4$\pi$ by spectrometer using magnetic adiabatic collimation with an electrostatic filter. Data presented 100 days run at Institut Laue Langevin 2013. sources systematic errors considered and included final result. obtain $a = -0.10430(84)$ most to date. From...