A5013618600- Atomic and Molecular Physics
- Muon and positron interactions and applications
- Advanced Chemical Physics Studies
- Solid State Laser Technologies
- Particle accelerators and beam dynamics
- Radiation Detection and Scintillator Technologies
- Advanced Fiber Laser Technologies
- Atomic and Subatomic Physics Research
- Nuclear physics research studies
- Experimental and Theoretical Physics Studies
- Laser Design and Applications
- Particle Detector Development and Performance
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Laser-Matter Interactions and Applications
- Particle physics theoretical and experimental studies
- Photorefractive and Nonlinear Optics
- Cold Atom Physics and Bose-Einstein Condensates
- Scientific Research and Discoveries
- X-ray Spectroscopy and Fluorescence Analysis
- Nuclear Physics and Applications
- Scientific Measurement and Uncertainty Evaluation
- Radioactive Decay and Measurement Techniques
- Advanced Frequency and Time Standards
- Plasma Diagnostics and Applications
Paul Scherrer Institute
2015-2024
ETH Zurich
2015-2024
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa
2023
École Polytechnique Fédérale de Lausanne
2022
Institute of Particle Physics
2015-2021
Max Planck Institute of Quantum Optics
2004-2017
Max Planck Society
2003-2016
Centre National de la Recherche Scientifique
2005-2011
Laboratoire Kastler Brossel
2005-2011
École Normale Supérieure - PSL
2011
Proton Still Too Small Despite a proton's tiny size, it is possible to measure its radius based on charge or magnetization distributions. Traditional measurements of proton were the scattering between protons and electrons. Recently, precision measurement line in spectrum muonium—an atom consisting muon, instead an electron—revealed inconsistent with that deduced from studies. Antognini et al. (p. 417 ; see Perspective by Margolis ) examined different spectral muonium, results less dependent...
The deuteron is too small, radius of the proton has remained a point debate ever since spectroscopy muonic hydrogen indicated large discrepancy from previously accepted value. Pohl et al. add an important clue for solving this so-called puzzle. They determined charge deuteron, nucleus consisting and neutron, transition frequencies in deuterium. Mirroring puzzle, was several standard deviations smaller than value inferred previous spectroscopic measurements electronic This independent points...
Abstract The energy levels of hydrogen-like atomic systems can be calculated with great precision. Starting from their quantum mechanical solution, they have been refined over the years to include electron spin, relativistic and field effects, tiny shifts related complex structure nucleus. These caused by nuclear are vastly magnified in formed a negative muon nucleus, so spectroscopy these muonic ions used investigate high Here we present measurement two 2S–2P transitions helium-4 ion that...
Laser spectroscopy of muonic atoms has been recently used to probe properties light nuclei with unprecedented precision. We introduce nuclear effects in hydrogen-like atoms, nucleon structure quantities (form factors, functions, polarizabilities), and their the Lamb shift hyperfine splitting (HFS) hydrogen (μH). Updated theory predictions for HFS μH are presented. review challenges ongoing effort measure ground-state its impact on our understanding spin structure. To narrow down this search,...
We report on a thin-disk Yb:YAG laser made from Q-switched oscillator and multipass amplifier delivering pulses of 48 mJ at 1030 nm. The peculiar requirements for this are the short delay time (< 500 ns) between electronic trigger optical output pulse randomness with which these triggers occur (with to next ges 1.5 ms). Details concerning dynamics (-switching cycle, intensity stabilization), layout given. Simulations beam propagation in based Collins integral measured aspherical components...
We plan to measure several 2S–2P transition frequencies in μ 4 He + and 3 by means of laser spectroscopy with an accuracy 50 ppm. This will lead a determination the corresponding nuclear rms charge radii relative × 10 −4 , limited uncertainty polarization contribution. First, these measurements help solve proton radius puzzle. Second, very precise are benchmarks for ab initio few-nucleon theories potentials. Finally when combined ongoing measurement 1S–2S enhanced bound-state QED test 1S Lamb shift .
The CREMA collaboration is pursuing a measurement of the ground-state hyperfine splitting (HFS) in muonic hydrogen ( \mu <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>μ</mml:mi></mml:math> p) with 1 ppm accuracy by means pulsed laser spectroscopy to determine two-photon-exchange contribution 2\times10^{-4}...
We report on muonium (Mu) emission into vacuum following μ(+) implantation in mesoporous thin SiO(2) films. obtain a yield of Mu (38±4)% at 250 K and (20±4)% 100 for 5 keV energy. From the energy dependence we determine diffusion constants these films: D(Mu)(250 K)=(1.6±0.1)×10(-4) cm(2)/s D(Mu)(100 K)=(4.2±0.5)×10(-5) cm(2)/s. Describing process as quantum mechanical tunneling from pore to pore, reproduce measured temperature ∼T(3/2) constant. extract potential barrier (-0.3±0.1) eV which...
Muonic atom spectroscopy-the measurement of the x rays emitted during formation process a muonic atom-has long standing history in probing shape and size nuclei. In fact, almost all stable elements have been subject to spectroscopy measurements absolute charge radii extracted from these typically offer highest accuracy available. However, so far only targets at least few hundred milligram could be used as it required stop muon beam directly target form atom. We developed new method relying...
We give a pedagogical description of the method to extract charge radii and Rydberg constant from laser spectroscopy in regular hydrogen (H) deuterium (D) atoms, that is part CODATA least-squares adjustment (LSA) fundamental physical constants. deuteron radius D alone 2.1415(45) fm. This value independent measurements lead proton radius, five times more accurate than found Adjustment 10. The improvement due use for transition atomic which can be inferred published data or PhD thesis.
The hyperfine splitting of the 5g→4f transitions in muonic 185,187Re has been measured using high resolution purity germanium detectors and compared to state-of-the-art atomic theoretical predictions. spectroscopic quadrupole moment extracted modern fitting procedures values available literature obtained from x rays natural rhenium. nuclear are 2.07(5) b 1.94(5) b, respectively for 185Re 187Re.1 MoreReceived 27 November 2019Accepted 21 February...
Hydrogen-like light muonic ions, in which one negative muon replaces all the electrons, are extremely sensitive probes of nuclear structure, because large mass increases tremendously wave function overlap with nucleus. Using pulsed laser spectroscopy we have measured three 2S-2P transitions helium-3 ion ($\mu^3$He$^+$), an formed by a and bare This allowed us to extract Lamb shift $E(2P_{1/2}-2S_{1/2})= 1258.598(48)^{\rm exp}(3)^{\rm theo}$ meV, 2P fine structure splitting $E_{\rm FS}^{\rm...
A $10\text{ }\text{ }\mathrm{MeV}/c$ positive muon beam was stopped in helium gas of a few mbar magnetic field 5 T. The ``swarm'' has been efficiently compressed from length 16 cm down to mm along the axis (longitudinal compression) using electrostatic fields. simulation reproduces low energy interactions slow muons gas. Phase space compression occurs on order microseconds, compatible with lifetime $2\text{ }\ensuremath{\mu}\mathrm{s}$. This paves way for preparation high-quality low-energy...
Precision spectroscopy of light muonic atoms provides unique information about the atomic and nuclear structure these systems thus represents a way to access fundamental interactions, properties constants. One application comprises determination absolute charge radii with unprecedented accuracy from measurements 2S - 2P Lamb shift. Here, we review recent results extracted hydrogen helium present experiment proposals Z ≥ 3. In addition, our approaches towards precise measurement Zemach in...
In April 2021, scientists active in muon physics met to discuss and work out the case for new High-Intensity Muon Beams (HIMB) project at PSI that could deliver of order $10^{10}$\,s$^{-1}$ surface muons experiments. Ideas concrete proposals were further substantiated over following months assembled present document. The high intensities will allow completely experiments with considerable discovery potential unique sensitivities. is outstanding extremely rich, ranging from fundamental...
Thin-disk laser pump layouts yielding an increased number of passes for a given module size and source quality are proposed. These result from general scheme based on merging two simpler optics arrangements. Some peculiar examples can be realized by adapting standard, commercially available with additional mirror pair. More yield better efficiency, opening the way usage active materials low absorption. In standard multipass design, scaling beam brings about increase in overall optical...
The present knowledge of Lamb shift, fine-, and hyperfine structure the 2S 2P states in muonic helium-3 ions is reviewed anticipation results a first measurement several → transition frequencies ion, μ3He+. This ion bound state single negative muon μ- bare nucleus (helion), 3He++. A term-by-term comparison all available sources, including new, updated, so far unpublished calculations, reveals reliable values uncertainties QED nuclear structure-dependent contributions to shift splitting....
Quantum interference between energetically close states is theoretically investigated, with the state structure being observed via laser spectroscopy. In this work, we focus on hyperfine of selected hydrogenic muonic isotopes, and how quantum affects measured Lamb shift. The process photon excitation subsequent decay implemented within framework nonrelativistic second-order perturbation theory. Due to its experimental interest, calculations are performed for hydrogen, deuterium, helium-3. We...
We demonstrate efficient transverse compression of a 12.5 MeV/c muon beam stopped in helium gas target featuring vertical density gradient and crossed electric magnetic fields. The stop distribution extending vertically over 14 mm was reduced to 0.25 size (rms) within 3.5 μs. simulation including cross sections for low-energy μ^{+}-He elastic charge exchange (μ^{+}↔ muonium) collisions describes the measurements well. By combining stage with previously demonstrated longitudinal stage, we can...