A5058214705- Atomic and Subatomic Physics Research
- Quantum, superfluid, helium dynamics
- Nuclear Physics and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Radiation Detection and Scintillator Technologies
- Dark Matter and Cosmic Phenomena
- Nuclear physics research studies
- Particle physics theoretical and experimental studies
- Advanced NMR Techniques and Applications
- Quantum Chromodynamics and Particle Interactions
- Advanced MRI Techniques and Applications
- Neutrino Physics Research
- Muon and positron interactions and applications
- Atomic and Molecular Physics
- Particle Detector Development and Performance
- Noncommutative and Quantum Gravity Theories
- Radioactive Decay and Measurement Techniques
- Scientific Measurement and Uncertainty Evaluation
- Physics of Superconductivity and Magnetism
- Scientific Research and Discoveries
- Photorefractive and Nonlinear Optics
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced Frequency and Time Standards
- Mechanical and Optical Resonators
- High-pressure geophysics and materials
Paul Scherrer Institute
2016-2025
University of Sussex
2020
Graz University of Technology
2016-2020
Laboratoire de Physique Corpusculaire de Caen
2017
Institut National de Physique Nucléaire et de Physique des Particules
2017
École Nationale Supérieure d'Ingénieurs de Caen
2017
Centre National de la Recherche Scientifique
2017
Physikalisch-Technische Bundesanstalt
2009-2017
Institute of Nuclear Physics, Polish Academy of Sciences
2017
KU Leuven
2017
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...
We present for the first time a detailed and comprehensive analysis of experimental results that set current world sensitivity limit on magnitude electric dipole moment (EDM) neutron. have extended enhanced our earlier to include recent developments in understanding effects gravity depolarizing ultracold neutrons (UCN); an improved calculation spectrum neutrons; conservative estimates other possible systematic errors, which are also shown be consistent with more measurements undertaken...
We report on a search for ultralow-mass axionlike dark matter by analyzing the ratio of spin-precession frequencies stored ultracold neutrons and 199Hg atoms an axion-induced oscillating electric dipole moment neutron axion-wind effect. No signal consistent with is observed axion mass range 10−24≤ma≤10−17 eV. Our null result sets first laboratory constraints coupling to gluons, which improve astrophysical limits up 3 orders magnitude, also improves previous nucleons factor 40.Received 29...
We report a measurement of the positive muon lifetime to precision 1.0 ppm; it is most precise particle ever measured. The experiment used time-structured, low-energy beam and segmented plastic scintillator array record more than 2×1012 decays. Two different stopping target configurations were employed in independent data-taking periods. combined results give τμ+(MuLan)=2 196 980.3(2.2) ps, 15 times as any previous experiment. gives value for Fermi constant: GF(MuLan)=1.166 378 8(7)×10−5...
We present a detailed report of the method, setup, analysis and results precision measurement positive muon lifetime. The experiment was conducted at Paul Scherrer Institute using time-structured, nearly 100%-polarized, surface beam segmented, fast-timing, plastic scintillator array. employed two target arrangements; magnetized ferromagnetic with ~4 kG internal magnetic field crystal quartz in 130 G external field. Approximately 1.6 x 10^{12} positrons were accumulated together data yield...
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...
The MuCap experiment at the Paul Scherrer Institute has measured rate L_S of muon capture from singlet state muonic hydrogen atom to a precision 1%. A beam was stopped in time projection chamber filled with 10-bar, ultra-pure gas. Cylindrical wire chambers and segmented scintillator barrel detected electrons decay. is determined difference between mu- disappearance free decay rate. result based on analysis 1.2 10^10 decays, which we extract = (714.9 +- 5.4(stat) 5.1(syst)) s^-1 derive...
The ultracold neutron (UCN) source at the Paul Scherrer Institute (PSI), Switzerland has started full beam operation in mid 2011. Since then, continuous improvements have led to an UCN intensity increase by about a factor of 80 comparison first on target. delivery two ports is now operating regular basis, with e.g. 17 million delivered one experiment over 200 s every 4 long pulse operated 480 interval.
Ultracold neutrons (UCNs) are key for precision studies of fundamental parameters the neutron and in searches new charge-parity-violating processes or exotic interactions beyond Standard Model particle physics. The most prominent example is search a permanent electric-dipole moment (nEDM). We have performed an experimental comparison leading UCN sources currently operating. used ``standard'' storage bottle with volume 32 liters, comparable size to nEDM experiments, which allows us compare...
It has been proposed that there could be a mirror copy of the standard model particles, restoring parity symmetry in weak interaction on global level. Oscillations between neutral particle, such as neutron, and its counterpart potentially answer various standing issues physics today. Astrophysical studies terrestrial experiments led by ultracold neutron storage measurements have investigated to mirror-neutron oscillations imposed constraints theoretical parameters. Recently, further analysis...
We present the design of a next-generation experiment, n2EDM, currently under construction at ultracold neutron source Paul Scherrer Institute (PSI) with aim carrying out high-precision search for an electric dipole moment neutron. The project builds on experience gained previous apparatus operated PSI until 2017, and is expected to deliver order magnitude better sensitivity provision further substantial improvements. An overview experimental method setup given, requirements are derived, its...
Abstract High-precision searches for an electric dipole moment of the neutron (nEDM) require stable and uniform magnetic field environments. We present recent achievements degaussing equilibrating magnetically shielded room (MSR) n2EDM experiment at Paul Scherrer Institute. final configuration that will be used after numerous studies. The optimized procedure results in a residual has been reduced by factor two. ultra-low is achieved with full magnetic-field-coil system, large vacuum vessel...
We present a coil system designed to generate highly uniform magnetic field for the n2EDM experiment at Paul Scherrer Institute. It consists of main B0 and set auxiliary coils mounted on cubic structure with side length 273cm , inside large magnetically shielded room (MSR). have assembled this characterized its performances mapping robot. The apparatus is able 1μT vertical relative root mean square deviation σ(Bz)/Bz=3×10-5 over volume interest, cylinder radius 40cm height 30cm . This level...
We performed ultracold neutron storage measurements to search for additional losses due (n) mirror-neutron (n′) oscillations as a function of an applied magnetic field B. In the presence mirror B′, would be maximal B≈B′. did not observe any indication nn′ and placed lower limit on oscillation time τnn′>12.0 s at 95% C.L. B′ between 0 12.5 μT.Received 26 May 2009DOI:https://doi.org/10.1103/PhysRevD.80.032003©2009 American Physical Society
The measurement of the neutron electric dipole moment (nEDM) constrains contribution CP-violating terms within both Standard Model and its extensions. experiment uses ultracold neutrons (UCN) stored in vacuum at room temperature. This technique provided last (and best) limit by RAL/Sussex/ILL collaboration 2006: dn < 2:9 × 10-26 e cm (90% C.L.). We aim to improve experimental sensitivity a factor 5 2-3 years, using an upgrade same apparatus. will take advantage increased density Paul...
The NPDGamma collaboration reports results from the first phase of a measurement parity violating up-down asymmetry Aγ with respect to neutron spin direction γ rays emitted in reaction n⃗+p→d+γ using capture polarized cold neutrons on protons liquid parahydrogen target. One expects parity-odd effects hadronic weak interaction between nucleons be induced by quarks. is dominated ΔI=1, 3S1-3P1 transition amplitude n-p system. was completed at Los Alamos Neutron Science Center spallation source...
We present a magnetometer based on optically pumped Cs atoms that measures the magnitude and direction of 1 μT magnetic field. Multiple circularly polarized laser beams were used to probe free spin precession atoms. The design was optimized for long-time stability achieves scalar resolution better than 300 fT integration times ranging from 80 ms 1000 s. best less reached with 1.6 6 able measure field 10 μrad s up 2000
We report the first observation of parity-violating 2.2 MeV gamma-ray asymmetry $A^{np}_\gamma$ in neutron-proton capture using polarized cold neutrons incident on a liquid parahydrogen target at Spallation Neutron Source Oak Ridge National Laboratory. isolates $\Delta I=1$, \mbox{$^{3}S_{1}\rightarrow {^{3}P_{1}}$} component weak nucleon-nucleon interaction, which is dominated by pion exchange and can be directly related to single coupling constant either DDH meson model or pionless EFT....
While the international nEDM collaboration at Paul Scherrer Institut (PSI) took data in 2017 that covered a considerable fraction of parameter space claimed potential signals hypothetical neutron (n) to mirror-neutron (n′) transitions, it could not test all signal regions various mirror magnetic fields. Therefore, new study n−n′ oscillations using stored ultracold neutrons (UCNs) is underway PSI, considerably expanding reach fields (B′) and oscillation time constants (τnn′). The apparatus...
The neutron gyromagnetic ratio has been measured relative to that of the 199Hg atom with an uncertainty 0.8 ppm. We employed apparatus where ultracold neutrons and mercury atoms are stored in same volume report result γn/γHg=3.8424574(30).
We report a new limit on possible short range spin-dependent interaction from the precise measurement of ratio Larmor precession frequencies stored ultracold neutrons and $^{199}$Hg atoms confined in same volume. The was performed $\sim$1$\mu$ T vertical magnetic holding field with apparatus searching for permanent electric dipole moment neutron at Paul Scherrer Institute. A coupling between freely precessing polarized spins unpolarized nucleons wall material can be investigated by tiny...
Magnetic-field uniformity is of the utmost importance in experiments to measure electric dipole moment neutron. A general parametrization magnetic field terms harmonic polynomial modes proposed, going beyond linear-gradients approximation. We review main undesirable effects nonuniformities: depolarization ultracold neutrons and Larmor frequency shifts mercury atoms. The theoretical predictions for these were verified by dedicated measurements with single-chamber neutron...
We present the magnetically shielded room (MSR) for n2EDM experiment at Paul Scherrer Institute which features an interior cubic volume with each side of length 2.92m, thus providing accessible space 25m3. The MSR has 87 openings up to 220mm diameter operate experimental apparatus inside, and intermediate between layers sensitive signal processing electronics. characterization measurements show a remanent magnetic field in central 1m3 below 100pT, 600pT entire inner volume, 4\,cm walls....