P. Schmidt-Wellenburg
A5104804999- Atomic and Subatomic Physics Research
- Quantum, superfluid, helium dynamics
- Cold Atom Physics and Bose-Einstein Condensates
- Dark Matter and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Particle physics theoretical and experimental studies
- Nuclear Physics and Applications
- Neutrino Physics Research
- Particle Detector Development and Performance
- Advanced MRI Techniques and Applications
- Computational Physics and Python Applications
- Advanced Frequency and Time Standards
- Particle accelerators and beam dynamics
- Advanced NMR Techniques and Applications
- Superconducting Materials and Applications
- Muon and positron interactions and applications
- Mechanical and Optical Resonators
- Physics of Superconductivity and Magnetism
- Photorefractive and Nonlinear Optics
- Noncommutative and Quantum Gravity Theories
- Quantum optics and atomic interactions
- Particle Accelerators and Free-Electron Lasers
- Medical Imaging Techniques and Applications
- Enhanced Oil Recovery Techniques
- Quantum Mechanics and Applications
Paul Scherrer Institute
2016-2025
ETH Zurich
2022-2023
Shanghai Jiao Tong University
2022-2023
European Organization for Nuclear Research
2022-2023
University of Pisa
2022-2023
Johannes Gutenberg University Mainz
2022-2023
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa
2022-2023
University of Sussex
2020
Laboratoire de Physique Subatomique et de Cosmologie
2018
Technical University of Munich
2003-2015
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...
With the long-standing tension between experiment and Standard-Model (SM) prediction in anomalous magnetic moment of muon, $a_\mu=(g-2)_\mu/2$, at level 3-4$\sigma$, it is natural to ask if there could be a sizable effect electric dipole (EDM) $d_\mu$ as well. In this context has often been argued that UV complete models electron EDM, which very precisely measured, excludes large $d_\mu$. However, recently observed 2.5$\sigma$ $a_e=(g-2)_e/2$, confirmed, requires muon sectors effectively...
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...
This paper outlines the design and development of a fast front-end electronic readout board for muon trigger detector in muEDM experiment at Paul Scherrer Institute. The detector, which consists gate aperture is strategically located end superconducting injection channel to generate signals magnetic kicker, activates upon muons into central region storage solenoid. Within field solenoid, system configuration optimized meet stringent performance specifications, including minimal signal...
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...
The electric dipole moments~(EDM) of fundamental particles inherently violate parity~(P) and time-reversal~(T) symmetries. By virtue the CPT theorem in quantum field theory, latter also implies violation combined charge-conjugation parity~(CP) symmetry. We aim to measure EDM muon using frozen-spin technique within a compact storage trap. This method exploits high effective field, \$E \approx 165\$ MV/m, experienced rest frame with momentum about 23 MeV/c when it passes through solenoidal...
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...
A new intense superthermal source for ultracold neutrons (UCN) was installed at a dedicated beam line the Institut Laue-Langevin. Incident with wavelength of 0.89 nm are converted to UCN in 5-liter volume filled superfluid $^{4}\mathrm{He}$ temperature about 0.7 K. The can be extracted room experiments. We present cryogenic setup source, characterization cold neutron beam, and production measurements, where density least 55 per ${\mathrm{cm}}^{3}$ determined.
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
This letter of intent proposes an experiment to search for electric dipole moment the muon based on frozen-spin technique. We intend exploit high field, $E=1{\rm GV/m}$, experienced in rest frame with a momentum $p=125 {\rm MeV/}c$ when passing through large magnetic field $|\vec{B}|=3{\rm T}$. Current fluxes at $μ$E1 beam line permit improved sensitivity $σ(d_μ)\leq 6\times10^{-23}e{\rm cm}$, about three orders magnitude more than current upper limit $|d_μ|\leq1.8\times10^{-19}e{\rm...
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....
We report the first successful extraction of accumulated ultracold neutrons (UCN) from a converter superfluid helium, in which they were produced by downscattering cold beam Munich research reactor. Windowless UCN is performed vertical direction through mechanical valve. This prototype versatile source comprised novel cryostat designed to keep portable and allow for rapid cooldown. measured time constants storage into detector at room temperature, with held various temperatures between 0.7...
The Surrounding Field Compensation (SFC) system described in this work is installed around the four-layer Mu-metal magnetic shield of neutron electric dipole moment spectrometer located at Paul Scherrer Institute. SFC reduces DC component external field by a factor about 20. Within control volume approximately 2.5 m × 3 m, disturbances are attenuated factors 5–50 bandwidth from 10−3 Hz up to 0.5 Hz, which corresponds integration times longer than several hundreds seconds and represent...