0000000000006138

AUTHOR

Ulrich Schmidt

showing 20 related works from this author

Ambient Temperature, Social Perception and Social Behavior

2020

The literature suggests that human perception and behavior vary with physical temperature. We provide an experimental test of how different ambient temperature conditions impact social behavior and social perception: Subjects went through a series of tasks measuring various aspects of social behavior and perception under three temperature conditions (cold vs. optimal vs. warm). Despite well-established findings on temperature effects, our data suggest that physical temperature has no relevant influence on social behavior and social perception. We corroborate our finding of a null effect by the use of equivalence testing and provide a discussion in the light of recent failed replication atte…

HistoryEquivalence testingPolymers and PlasticsSocial perceptionField (Bourdieu)Perceptionmedia_common.quotation_subjectBusiness and International ManagementPsychologySocial preferencesIndustrial and Manufacturing EngineeringCognitive psychologymedia_commonSSRN Electronic Journal
researchProduct

Cubic boron nitride: A new prospective material for ultracold neutron application

2009

Abstract At the ultracold neutron (UCN) source of the TRIGA research reactor in Mainz, we have measured for the first time the material optical wall-potential of cubic boron nitride. The measurements were performed with a time-of-flight (TOF) spectrometer. The samples investigated had a wall-potential of ( 305 ± 15 ) neV . This value is in good agreement with the result extracted from neutron reflectometry data and theoretical expectations. Because of its high critical velocity for UCN and its good dielectric characteristics, cubic boron nitride coatings (isotopically enriched) will be useful for a number of applications in UCN experiments.

PhysicsNuclear and High Energy PhysicsSpectrometerPhysics::Instrumentation and DetectorsFOS: Physical sciencesDielectricCritical ionization velocityTRIGACondensed Matter::Materials Sciencechemistry.chemical_compoundNuclear magnetic resonancechemistryBoron nitrideNeutronResearch reactorNeutron reflectometryNuclear Experiment (nucl-ex)Atomic physicsNuclear ExperimentNuclear ExperimentInstrumentation
researchProduct

Highly resolved observations of trace gases in the lowermost stratosphere and upper troposphere from the Spurt project: an overview

2005

International audience; During SPURT (Spurenstofftransport in der Tropopausenregion, trace gas transport in the tropopause region) we performed measurements of a wide range of trace gases with different lifetimes and sink/source characteristics in the northern hemispheric upper troposphere (UT) and lowermost stratosphere (LMS). A large number of in-situ instruments were deployed on board a Learjet 35A, flying at altitudes up to 13.7 km, at times reaching to nearly 380 K potential temperature. Eight measurement campaigns (consisting of a total of 36 flights), distributed over all seasons and typically covering latitudes between 35° N and 75° N in the European longitude sector (10° W?20° E), …

[SDU.OCEAN]Sciences of the Universe [physics]/Ocean AtmosphereAtmospheric ScienceComplete data010504 meteorology & atmospheric sciences010502 geochemistry & geophysicsAtmospheric sciences01 natural scienceslcsh:QC1-999JLatitudeTrace gasTropospherelcsh:Chemistrylcsh:QD1-99913. Climate actionClimatologyddc:550Potential temperatureEnvironmental scienceTropopauseLongitudeStratospherelcsh:Physics0105 earth and related environmental sciences
researchProduct

Spin clocks: Probing fundamental symmetries in nature

2013

The detection of the free precession of co-located 3He/129Xe nuclear spins (clock comparison) is used as ultra-sensitive probe for non-magnetic spin interactions, since the magnetic dipole interaction (Zeeman-term) drops out in the weighted frequency difference, i.e., Δω = ωHe- γHe/γXe·ωXe of the respective Larmor frequencies. Recent results are reported on searches for (i) short-range P- and T-violating interactions between nucleons, and (ii) Lorentz violating signatures by monitoring the Larmor frequencies as the laboratory reference frame rotates with respect to distant stars (sidereal modulation). Finally, a new experimental initiative to search for an electric dipole moment of 129Xe (C…

Physicssymbols.namesakeElectric dipole momentSpinsSidereal timeLorentz transformationQuantum mechanicsPrecessionsymbolsGeneral Physics and AstronomySpin (physics)NucleonMagnetic dipoleAnnalen der Physik
researchProduct

A new limit of the 129 Xenon Electric Dipole Moment

2019

We report on the first preliminary result of our 129Xe EDM measurement performed by the MIXed collaboration. The aim of this report is to demonstrate the feasibility of a new method to set limits on nuclear EDMs by investigating the EDM of the diamagnetic 129Xe atoms. In our setup, hyperpolarized 3He serves as a comagnetometer needed to suppress magnetic field fluctuations. The free induction decay of the two polarized spin species is directly measured by low noise DC SQUIDs, and the weighted phase difference extracted from these measurements is used to determine a preliminary upper limit on the 129Xe EDM.

Physics010308 nuclear & particles physicsPhysicsQC1-99901 natural sciencesMagnetic fieldFree induction decayElectric dipole momentHelium-30103 physical sciencesIsotopes of xenonDiamagnetismddc:530Atomic physics010306 general physicsSpin (physics)Isotopes of helium
researchProduct

Neutron Decay with PERC: a Progress Report

2011

The PERC collaboration will perform high-precision measurements of angular correlations in neutron beta decay at the beam facility MEPHISTO of the Forschungs-Neutronenquelle Heinz Maier-Leibnitz in Munich, Germany. The new beam station PERC, a clean, bright, and versatile source of neutron decay products, is designed to improve the sensitivity of neutron decay studies by one order of magnitude. The charged decay products are collected by a strong longitudinal magnetic field directly from inside a neutron guide. This combination provides the highest phase space density of decay products. A magnetic mirror serves to perform precise cuts in phase space, reducing related systematic errors. The …

PhysicsHistoryProtonComputer Science ApplicationsEducationMagnetic fieldddc:Nuclear physicsMagnetic mirrorPhase spaceNeutronSpectroscopyBeam (structure)Order of magnitude
researchProduct

Limit on Lorentz andCPTviolation of the bound neutron using a free precessionHe3/Xe129comagnetometer

2010

We report on the search for Lorentz-violating sidereal variations of the frequency difference of colocated spin species while the Earth and hence the laboratory reference frame rotates with respect to a relic background field. The comagnetometer used is based on the detection of freely precessing nuclear spins from polarized 3 He and 129 Xe gas samples using SQUIDs as low-noise magnetic flux detectors. As result we can determine the limit for the equatorial component of the background field interacting with the spin of the bound neutron to be b n ⊥ < 3.7 · 10- 32 GeV (95% C.L.).

PhysicsNuclear and High Energy PhysicsSpinsField (physics)Condensed matter physicsLorentz transformationMagnetic fluxNuclear physicssymbols.namesakeSidereal timePrecessionsymbolsNeutronSpin (physics)Physical Review D
researchProduct

Allmendingeret al.Reply:

2014

PhysicsGeneral Physics and AstronomyPhysical Review Letters
researchProduct

Constraints on Spin-Dependent Short-Range Interaction between Nucleons

2013

We report on the search for a new spin-dependent P- and T-violating interaction between nucleons mediated by light, pseudoscalar bosons such as the axion which was invented to solve the strong CP problem. Our experimental approach is to use an ultra-sensitive low-field magnetometer based on the detection of free precession of co-located 3He and 129Xe nuclear spins using SQUIDs as low-noise magnetic flux detectors. In the presence of an unpolarized mass the precession frequency shif

PhysicsLarmor precessionParticle physicsSpinsHigh Energy Physics::PhenomenologyGeneral Physics and AstronomyFOS: Physical sciencesHigh Energy Physics - ExperimentMagnetic fieldPseudoscalarHigh Energy Physics - Experiment (hep-ex)NeutronNucleonAxionBoson
researchProduct

Ex vivo and in vivo evaluation of [18F]PR04.MZ in rodents: a selective dopamine transporter imaging agent.

2009

N-4-Fluorobut-2-yn-1-yl-2beta-carbomethoxy-3beta-phenyltropane (PR04.MZ) has been developed as dopamine transporter (DAT) ligand for molecular imaging. It contains a terminally fluorinated, conformationally constrained nitrogen substituent that is well suited for the introduction of fluorine-18. The present report describes the pharmacological characterisation of [18F]PR04.MZ. The ligand shows an IC50 value of 2 nM against human DAT, whereas the IC50 value against human serotonin transporter and human noradrenalin transporter are lower (110 nM and 22 nM, respectively). Furthermore, its ex vivo organ distribution, its binding profile in the rat brain and reversibility of binding were examine…

MaleFluorine RadioisotopesDopamine Plasma Membrane Transport ProteinsBiochemistryCell LineRats Sprague-DawleyIn vivoDrug DiscoveryAnimalsHumansTissue DistributionGeneral Pharmacology Toxicology and PharmaceuticsSerotonin transporterDopamine transporterPharmacologySerotonin Plasma Membrane Transport ProteinsDopamine Plasma Membrane Transport ProteinsNorepinephrine Plasma Membrane Transport ProteinsbiologyChemistryOrganic ChemistryTransporterLigand (biochemistry)Imaging agentRatsBiochemistryPositron-Emission Tomographybiology.proteinBiophysicsMolecular MedicineRadiopharmaceuticalsEx vivoTropanesChemMedChem
researchProduct

New Limit on Lorentz-Invariance- andCPT-Violating Neutron Spin Interactions Using a Free-Spin-PrecessionHe3-Xe129Comagnetometer

2014

We report on the search for a $CPT$- and Lorentz-invariance-violating coupling of the $^{3}\mathrm{He}$ and $^{129}\mathrm{Xe}$ nuclear spins (each largely determined by a valence neutron) to posited background tensor fields that permeate the Universe. Our experimental approach is to measure the free precession of nuclear spin polarized $^{3}\mathrm{He}$ and $^{129}\mathrm{Xe}$ atoms in a homogeneous magnetic guiding field of about 400 nT using ${\mathrm{LT}}_{C}$ SQUIDs as low-noise magnetic flux detectors. As the laboratory reference frame rotates with respect to distant stars, we look for a sidereal modulation of the Larmor frequencies of the colocated spin samples. As a result we obtain…

PhysicsStarsValence (chemistry)SpinsQuantum mechanicsGeneral Physics and AstronomyNeutronLorentz covarianceSpin (physics)Magnetic fluxTensor fieldPhysical Review Letters
researchProduct

Design of the Magnet System of the Neutron Decay Facility PERC

2018

The PERC (Proton and Electron Radiation Channel) facility is currently under construction at the research reactor FRM II, Garching. It will serve as an intense and clean source of electrons and protons from neutron beta decay for precision studies. It aims to contribute to the determination of the Cabibbo-Kobayashi-Maskawa quark-mixing element $V_{ud}$ from neutron decay data and to search for new physics via new effective couplings. PERC's central component is a 12m long superconducting magnet system. It hosts an 8m long decay region in a uniform field. An additional high-field region selects the phase space of electrons and protons which can reach the detectors and largely improves system…

Physics - Instrumentation and Detectorsmagnet: designProtonQC1-999FOS: Physical sciencesSuperconducting magnetElectron[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]01 natural sciences7. Clean energyelectron: particle sourcep: particle sourceNuclear physics0103 physical sciencesResearch reactorNeutron[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]Nuclear Experiment (nucl-ex)010306 general physicsNuclear ExperimentPhysicsn: semileptonic decay010308 nuclear & particles physicsPhysicsInstrumentation and Detectors (physics.ins-det)magnet: superconductivityMagnetic fieldbeam opticsMagnetPhase spaceHigh Energy Physics::Experiment
researchProduct

HP-Xe to go: Storage and Transportation of Hyperpolarized 129-Xe

2016

Abstract Recently the spin–lattice relaxation time T 1 of hyperpolarized (HP)- 129 Xe was significantly improved by using uncoated and Rb-free storage vessels of GE180 glass. For these cells, a simple procedure was established to obtain reproducible wall relaxation times of about 18 h. Then the limiting relaxation mechanism in pure Xe is due to the coupling between the nuclear spins and the angular momentum of the Xe–Xe van-der-Waals-molecules. This mechanism can be significantly reduced by using different buffer gases of which CO 2 was discovered to be the most efficient so far. From these values, it was estimated that for a 1:1 mixture of HP-Xe with CO 2 a longitudinal relaxation time of …

CouplingNuclear and High Energy PhysicsAngular momentumSpinsCondensed matter physicsChemistryRelaxation (NMR)BiophysicsAnalytical chemistrychemistry.chemical_element010402 general chemistryCondensed Matter Physics01 natural sciencesBiochemistry0104 chemical sciencessymbols.namesakeXenon0103 physical sciencessymbolsvan der Waals forceTotal pressure010306 general physicsLongitudinal Relaxation Time
researchProduct

Measurement of the Permanent Electric Dipole Moment of the $^{129}$Xe Atom

2019

We report on a measurement of the $CP$-violating permanent electric dipole moment (EDM) of the neutral $^{129}\mathrm{Xe}$ atom. Our experimental approach is based on the detection of the free precession of co-located nuclear spin-polarized $^{3}\mathrm{He}$ and $^{129}\mathrm{Xe}$ samples. The EDM measurement sensitivity benefits strongly from long spin coherence times of several hours achieved in diluted gases and homogeneous weak magnetic fields of about 400 nT. A finite EDM is indicated by a change in the precession frequency, as an electric field is periodically reversed with respect to the magnetic guiding field. Our result $(\ensuremath{-}4.7\ifmmode\pm\else\textpm\fi{}6.4)\ifmmode\t…

Larmor precessionPhysicsField (physics)Atomic Physics (physics.atom-ph)FOS: Physical sciences01 natural sciences010305 fluids & plasmasMagnetic fieldPhysics - Atomic PhysicsElectric dipole momentElectric field0103 physical sciencesAtomddc:530Sensitivity (control systems)Atomic physics010306 general physicsSpin (physics)
researchProduct

Improved determination of the β−ν¯e angular correlation coefficient a in free neutron decay with the aSPECT spectrometer

2020

We report on a precise measurement of the electron-antineutrino angular correlation ($a$ coefficient) in free neutron beta-decay from the $a$SPECT experiment. The $a$ coefficient is inferred from the recoil energy spectrum of the protons which are detected in 4$\pi$ by the $a$SPECT spectrometer using magnetic adiabatic collimation with an electrostatic filter. Data are presented from a 100 days run at the Institut Laue Langevin in 2013. The sources of systematic errors are considered and included in the final result. We obtain $a = -0.10430(84)$ which is the most precise measurement of the neutron $a$ coefficient to date. From this, the ratio of axial-vector to vector coupling constants is …

PhysicsCoupling constantSpectrometer010308 nuclear & particles physicsSpectrum (functional analysis)Lambda01 natural sciencesCollimated lightFilter (large eddy simulation)0103 physical sciencesNeutronAtomic physicsNuclear Experiment010306 general physicsAdiabatic processPhysical Review C
researchProduct

Limit on Lorentz-Invariance- and CPT-Violating Neutron Spin Interactions Using a $^3$He-$^{129}$Xe Comagnetometer

2016

We performed a search for a Lorentz-invariance- and CPT-violating coupling of the $^3$He and $^{129}$Xe nuclear spins to posited background fields. Our experimental approach is to measure the free precession of nuclear spin polarized $^3$He and $^{129}$Xe atoms using SQUID detectors. As the laboratory reference frame rotates with respect to distant stars, we look for a sidereal modulation of the Larmor frequencies of the co-located spin samples. As a result we obtain an upper limit on the equatorial component of the background field $\tilde{b}^n_{\bot}&lt; 8.4 \cdot 10^{-34}$ GeV (68\% C.L.). Furthermore, this technique was modified to search for an electric dipole moment (EDM) of $^{129}$X…

PhysicsSpinsField (physics)Atomic Physics (physics.atom-ph)FOS: Physical sciences02 engineering and technologyLorentz covariance021001 nanoscience & nanotechnology01 natural sciencesPhysics - Atomic PhysicsHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Sidereal timeQuantum electrodynamics0103 physical sciencesPrecessionNeutron010306 general physics0210 nano-technologyAnisotropySpin (physics)
researchProduct

Oscillatory brain activity associated with skin conductance responses in the context of risk

2021

Understanding the neural correlates of risk-sensitive skin conductance responses can provide insights into their connection to emotional and cognitive processes. To provide insights into this connection, we studied the cortical correlates of risk-sensitive skin conductance peaks using electroencephalography. Fluctuations in skin conductance responses were elicited while participants played a threat-of-shock card game. Precise temporal information about skin conductance peaks was obtained by applying continuous decomposition analysis on raw electrodermal signals. Shortly preceding skin conductance peaks, we observed a decrease in oscillatory power in the frequency range between 3 and 17 Hz i…

MalePhysicsintegumentary systemPhysiologyBrain activity and meditationGeneral NeuroscienceResolution (electron density)Context (language use)Galvanic Skin ResponseBrain WavesArousalVisual processingYoung AdultRisk-TakingHumansOccipital LobeSkin conductanceNeuroscienceJournal of Neurophysiology
researchProduct

Search for Spin-Dependent Short-Range Interaction with an 3He/129Xe Clock Comparison Experiment

2016

We performed an experiment to search for a new spin-dependent P- and T-violating nucleon–nucleon interaction [Formula: see text] which is mediated by light pseudoscalar bosons such as axions or axionlike particles. This interaction causes a shift [Formula: see text] in the precession frequency of nuclear spin polarized gases in the presence of an unpolarized mass. In order to measure this frequency shift a 3He/[Formula: see text]Xe comagnetometer was used which is based on the detection of free precession of 3He and [Formula: see text]Xe nuclear spins using SQUIDs as detectors. For the upper limit of [Formula: see text] we obtained 7.1[Formula: see text]nHz. With this value, an upper limit…

Larmor precessionPhysicsParticle physics01 natural sciencesNuclear physicsPseudoscalarOrders of magnitude (time)0103 physical sciencesPrecessionNeutron010306 general physicsSpin (physics)AxionBosonInternational Journal of Modern Physics: Conference Series
researchProduct

Probing Lorentz invariance and other fundamental symmetries in3He/129Xe clock-comparison experiments

2011

We discuss the design and performance of a very sensitive low-field magnetometer based on the detection of free spin precession of gaseous, nuclear polarized 3He or 129Xe samples with a SQUID as magnetic flux detector. Characteristic spin precession times T*2 of up to 60 h were measured in low magnetic fields (about 1μT) and in the regime of motional narrowing. With the detection of the free precession of co-located 3He/129Xe nuclear spins (clock comparison), the device can be used as ultra-sensitive probe for non-magnetic spin interactions, since the magnetic dipole interaction (Zeeman-term) drops out in the weighted frequency difference, i.e., Δω = ωHe− γHe/γXe·ωXe. We report on searches …

Larmor precessionPhysicsHistorySpin polarizationLorentz covarianceComputer Science ApplicationsEducationMagnetic fieldThomas precessionClassical mechanicsQuantum electrodynamicsPrecessionSpin (physics)Magnetic dipoleJournal of Physics: Conference Series
researchProduct

Zur Ökologie Abwasserbelasteter Altrheine

1977

The backwaters of the Upper Rhine can be divided into two types, namely the Sondernheim type and the Leimersheim type. The first one obtains its water mainly from small tributaries of the Rhine, the latter one by the Rhine itself. Both of them are polluted to nearly the same extent by organic matter. In the Sondernheim type biological decomposition starts intensively. It leads to mass-production of a few animal species in the upper, to less production of a large number of animal species in the lower part of its flow. In the Leimersheim type neither biological decomposition, nor mass-production nor a high species-diversity are to be observed. The possible causes of this difference are under …

chemistry.chemical_classificationHydrologygeographygeography.geographical_feature_categorychemistryTributaryEnvironmental scienceOrganic matterAnimal speciesDecomposition
researchProduct