A5026790441- Atomic and Subatomic Physics Research
- Advanced NMR Techniques and Applications
- Nuclear Physics and Applications
- Quantum, superfluid, helium dynamics
- Solid-state spectroscopy and crystallography
- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Electron Spin Resonance Studies
- Superconducting Materials and Applications
- High-pressure geophysics and materials
- Radiation Detection and Scintillator Technologies
- NMR spectroscopy and applications
- Magnetic properties of thin films
- Muon and positron interactions and applications
- Dark Matter and Cosmic Phenomena
- X-ray Spectroscopy and Fluorescence Analysis
- Molecular spectroscopy and chirality
- Particle Accelerators and Free-Electron Lasers
- Particle Detector Development and Performance
- Magnetic Properties and Applications
- Advanced Condensed Matter Physics
- Advanced MRI Techniques and Applications
- Radiation Therapy and Dosimetry
Paul Scherrer Institute
2015-2024
Center for Integrated Quantum Science and Technology
2021
École Polytechnique Fédérale de Lausanne
2008-2021
OmniVision Technologies (Germany)
2021
Universität Ulm
2021
ETH Zurich
1990-2013
University of Bern
2013
École Normale Supérieure - PSL
2013
Universidad de Zaragoza
2009
Institut d'Astrophysique Spatiale
2009
We present the final results of spin asymmetries A1 and structure functions g1 proton deuteron in kinematic range 0.0008<x<0.7 0.2<Q2<100GeV2. For determination A1, addition to usual method which employs inclusive scattering events includes a large radiative background at low x, we use new minimizes by selecting with least one hadron as well muon state. find that this gives smaller errors for x<0.02, so it is combined provide optimal set results.Received 18 May...
We have measured the spin-dependent structure function g1p in inclusive deep-inelastic scattering of polarized muons off protons, kinematic range 0.003<x<0.7 and 1GeV2<Q2<60GeV2. A next-to-leading order QCD analysis is used to evolve g1p(x,Q2) a fixed Q02. The first moment at Q02=10GeV2 Γ1p=0.136±0.013 (stat) ±0.009 (syst) ±0.005 (evol). This result below prediction Ellis-Jaffe sum rule by more than two standard deviations. singlet axial charge a0 found be 0.28±0.16. In Adler-Bardeen...
Major breakthroughs have recently been reported that can help overcome two inherent drawbacks of NMR: the lack sensitivity and limited memory longitudinal magnetization. Dynamic nuclear polarization (DNP) couples spins to large reservoir electrons, thus making it possible detect dilute endogenous substances in magnetic resonance spectroscopy (MRS) imaging (MRI). We designed a method preserve enhanced ("hyperpolarized") magnetization by conversion into long-lived states (LLS). It is shown...
Abstract For most of the last forty years, techniques Dynamic Nuclear Polarization (DNP) have been confined to particle‐physics laboratories building polarized targets, but recently it has shown that samples similar a solid target can be transformed into room temperature liquid solutions while retaining high nuclear polarization. This method “hyperpolarization” is interest in NMR/MRI/MRS. We describe 3.35 T DNP/9.4 MRI installation based on continuous‐flow cryostat, using standard wide‐bore...
The efficiency of dissolution dynamic nuclear polarization can be boosted by Hartmann–Hahn cross at temperatures near 1.2 K. This enables high throughput hyperpolarized solutions with substantial gains in buildup times and levels. During transport, the 13C spin P(13C) merely decreases from 45 to 40%.
Nuclear spin hyperpolarization provides a promising route to overcome the challenges imposed by limited sensitivity of nuclear magnetic resonance. Here we demonstrate that dissolution spin-polarized pentacene-doped naphthalene crystals enables transfer polarization target molecules via intermolecular cross-relaxation at room temperature and moderate fields (1.45 T). This makes it possible exploit high optically polarized crystals, while mitigating its external nuclei. With this method,...
We present a new measurement of the spin-dependent structure function g1d deuteron in deep inelastic scattering 190 GeV polarised muons on deuterons, kinematic range 0.003 < x 0.7 and 1 GeV2 Q2 60 GeV2. This is found to be negative at small x. The first moment Γ1d=∫01g1ddx evaluated Q02 = 10 0.034 ± 0.009 (stat.) 0.006 (syst.). value below Ellis-Jaffe sum rule prediction by three standard deviations. Using our earlier determination Γ1p, we obtain Γ1p − Γ1n 0.199 0.038 which agrees with Bjorken rule.
We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering polarised muons on protons deuterons in the range 0.003<x<0.7 Q2>1 GeV2. Compared to our previous publication this subject, with new data statistical errors have been reduced by nearly factor two. From these inclusive we determine quark distributions valence quarks non-strange sea at Q2=10 The u distribution, Δuv(x), is positive polarisation increases x. d...
Apart from their very classical use to build polarized targets for particle physics, the methods of dynamic nuclear polarization (DNP) have more recently found application sensitivity enhancement in high-resolution NMR, both solid and liquid state. It is often thought that possible signal such applications deteriorates when DNP performed at higher fields. We show a dissolution-DNP method uses conventional (2,2,6,6-tetramethylpiperidine 1-oxyl) radicals as paramagnetic agent, this not case...
In recent years methods of creating 'hyperpolarized' substances have gained considerable attention in biomedical magnetic resonance and dynamic nuclear polarization (DNP) is one the most promising, especially for imaging applications. Here we present results DNP studies on protons C-13 nuclei frozen solutions sodium acetate glycine, dissolved water-ethanol water-glycerol, doped with TEMPO free radicals EHBA-Cr-V complexes. Up to 14% close 50% proton were achieved at similar 1.2K a field 3.5...
We present a next-to-leading order QCD analysis of the presently available data on spin structure function g1 including final from Spin Muon Collaboration. results for first moments proton, deuteron, and neutron functions, determine singlet nonsinglet parton distributions in two factorization schemes. also test Bjorken sum rule find agreement with theoretical prediction at level 10%.Received 18 May 1998DOI:https://doi.org/10.1103/PhysRevD.58.112002©1998 American Physical Society
We present a measurement of the longitudinal spin cross section asymmetry for deep-inelastic muon-nucleon interactions with two high transverse momentum hadrons in final state. Two methods event classification are used to increase contribution photon-gluon fusion process above 30%. The most effective one, based on neural network approach, provides asymmetries Al→NlhhXp=0.030±0.057(stat)±0.010(syst) and Al→NlhhXd=0.070±0.076(stat)±0.010(syst). From these values we derive an averaged gluon...
We present a new measurement of the spin-dependent structure function g1d deuteron from deep inelastic scattering 190 GeV polarized muons on deuterons. The results are combined with our previous measurements g1d. A perturbative QCD evolution in next-to-leading order is used to compute g1d(x) at constant Q2. At Q2 = 10 GeV2, we obtain first moment Γ1d=∫1dg1ddx=0.041±0.008, flavour-singlet axial charge nucleon a0 0.30 ± 0.08, and an strange quark as −0.09 0.03. Using earlier determination Γ1p,...
We measured the spin asymmetry in scattering of 100 GeV longitudinally-polarized muons on transversely polarized protons. The was found to be compatible with zero kinematic range 0.006 < x 0.6, 1 Q2 30GeV2. From this result we derive upper limits for virtual photon-proton A2, and structure function g2. For 0.15, A2 is significantly smaller than its positivity limit √R.
Hyperpolarized magnetic resonance via dissolution dynamic nuclear polarization necessitates the transfer of hyperpolarized molecules from polarizer to imager prior in vivo measurements. This process leads unavoidable losses polarization, which are difficult evaluate once solution has been injected into an animal. We propose a method measure inside bore, 3 s following dissolution, at time injection, using precise quantification infusate concentration. situ allows for distinguishing between...
We present the results of spin asymmetries ${A}_{1}$ proton and deuteron in kinematic region extending down to $x=6\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$ ${Q}^{2}=0.01{\mathrm{GeV}}^{2}.$ The data were taken with a dedicated low x trigger, which required hadron detection addition scattered muon, so as reduce background at x. complement our previous measurements two sets are consistent overlap region. No significant effects found newly explored
We present a new measurement of the virtual photon proton asymmetry A1p from deep inelastic scattering polarized muons on protons in kinematic range 0.0008 < x 0.7 and 0.2 Q2 100 GeV2. With this, statistical uncertainty our has improved by factor 2 compared to previous measurements. The spin-dependent structure function g1p is determined for data with > 1 A perturbative QCD evolution next-to-leading order used determine g1p(x) at constant Q2. At = 10 GeV2 we find, measured range,...
Abstract Lithium is widely used in psychotherapy. The 6 Li isotope has a long intrinsic longitudinal relaxation time T 1 on the order of minutes, making it an ideal candidate for hyperpolarization experiments. In present study we demonstrated that lithium‐6 can be readily hyperpolarized within 30 min, while retaining polarization decay minute. We intrinsically detection 500 nM contrast agent vitro. Hyperpolarized was administered to rat and its signal retained 70 sec vivo. Localization...
A high throughput method was designed to produce hyperpolarized gases by combining low-temperature dynamic nuclear polarization with a sublimation procedure. It is illustrated applications $^{129}\mathrm{Xe}$ magnetic resonance in xenon gas, leading signal enhancement of 3 4 orders magnitude compared the room-temperature thermal equilibrium at 7.05 T.