A5062014765- Particle physics theoretical and experimental studies
- Neutrino Physics Research
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- Muon and positron interactions and applications
- Particle accelerators and beam dynamics
- Nuclear Physics and Applications
- Atomic and Molecular Physics
- Computational Physics and Python Applications
- Quantum Chromodynamics and Particle Interactions
- Superconducting Materials and Applications
- Nuclear reactor physics and engineering
- Astrophysics and Cosmic Phenomena
- X-ray Spectroscopy and Fluorescence Analysis
- Plasma Diagnostics and Applications
- Particle Accelerators and Free-Electron Lasers
- Spacecraft Design and Technology
- Quantum Information and Cryptography
- Medical Imaging Techniques and Applications
- Radiation Therapy and Dosimetry
- Advanced MEMS and NEMS Technologies
- Advancements in PLL and VCO Technologies
- Electrohydrodynamics and Fluid Dynamics
Paul Scherrer Institute
2015-2024
Vifor Pharma (Switzerland)
2023-2024
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa
2006-2024
University of Pisa
2011-2024
ETH Zurich
2022-2023
Shanghai Jiao Tong University
2022-2023
European Organization for Nuclear Research
2022-2023
Johannes Gutenberg University Mainz
2022-2023
Scuola Normale Superiore
2005
The final results of the search for lepton flavour violating decay $$\mathrm {\mu }^+ \rightarrow \mathrm {e}^+ {\gamma }$$ based on full dataset collected by MEG experiment at Paul Scherrer Institut in period 2009–2013 and totalling $$7.5\times 10^{14}$$ stopped muons target are presented. No significant excess events is observed with respect to expected background a new upper limit branching ratio this $$ \mathcal{B} (\mu ^+ \mathrm{e}^+ \gamma ) < 4.2 \times 10^{-13}$$ (90 % confidence...
The analysis of a combined data set, totaling 3.6 × 10(14) stopped muons on target, in the search for lepton flavor violating decay μ(+) → e(+)γ is presented. collected by MEG experiment at Paul Scherrer Institut show no excess events compared to background expectations and yield new upper limit branching ratio this 5.7 10(-13) (90% confidence level). This represents four times more stringent than previous world best set MEG.
The MEG experiment, designed to search for the mu+->e+ gamma decay at a 10^-13 sensitivity level, completed data taking in 2013. In order increase reach of experiment by an magnitude level 6 x 10-14 branching ratio, total upgrade, involving substantial changes has been undertaken, known as II. We present both motivation upgrade and detailed overview design expected detector performance.
We present a new result based on an analysis of the data collected by MEG detector at Paul Scherrer Institut in 2009 and 2010, search lepton-flavor-violating decay μ+→e+γ. The likelihood combined sample, which corresponds to total 1.8×1014 muon decays, gives 90% C.L. upper limit 2.4×10−12 branching ratio μ+→e+γ decay, constituting most stringent existence this date.Received 31 July 2011DOI:https://doi.org/10.1103/PhysRevLett.107.171801© 2011 American Physical Society
Abstract The MEG II experiment, based at the Paul Scherrer Institut in Switzerland, reports result of a search for decay $$\upmu ^+ \rightarrow {\textrm{e}}^+ \upgamma $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msup> <mml:mi>μ</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo>→</mml:mo> <mml:mtext>e</mml:mtext> </mml:mrow> <mml:mi>γ</mml:mi> </mml:math> from data taken first physics run 2021. No excess events over expected background is observed, yielding an...
We propose an experiment (Mu3e) to search for the lepton flavour violating decay mu+ -> e+e-e+. aim ultimate sensitivity of one in 10^16 mu-decays, four orders magnitude better than previous searches. This is made possible by exploiting modern silicon pixel detectors providing high spatial resolution and hodoscopes using scintillating fibres tiles precise timing information at particle rates.
The MEG (Mu to Electron Gamma) experiment has been running at the Paul Scherrer Institut (PSI), Switzerland since 2008 search for decay μ +→e+ γ by using one of most intense continuous + beams in world. This paper presents components: positron spectrometer, including a thin target, superconducting magnet, set drift chambers measuring muon vertex and momentum, timing counter time, liquid xenon detector photon energy, position time. trigger system, read-out electronics data acquisition system...
The Mu3e experiment aims to find or exclude the lepton flavour violating decay $\mu \rightarrow eee$ at branching fractions above $10^{-16}$. A first phase of using an existing beamline Paul Scherrer Institute (PSI) is designed reach a single event sensitivity $2\cdot 10^{-15}$. We present overview all aspects technical design and expected performance phase~I detector. high rate up $10^{8}$ muon decays per second low momenta electrons positrons pose unique set challenges, which we tackle...
Abstract The workshop “Shedding light on X17” brings together scientists looking for the existence of a possible new particle, often referred to as X17. This hypothetical particle can explain resonant structure observed at $$\sim $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>∼</mml:mo> </mml:math> 17 MeV in invariant mass electron-positron pairs, produced after excitation nuclei such $$^8\hbox {Be}$$ <mml:mrow> <mml:msup> <mml:mrow /> <mml:mn>8</mml:mn> </mml:msup>...
Abstract The MEG II experiment, located at the Paul Scherrer Institut (PSI) in Switzerland, is successor to which completed data taking 2013. started fully operational 2021, with goal of improving sensitivity $$\upmu ^+ \rightarrow {\textrm{e}}^+ \upgamma $$ <mml:math...
The MEG experiment took data at the Paul Scherrer Institute in years 2009–2013 to test violation of lepton flavor conservation law, which originates from an accidental symmetry that Standard Model elementary particle physics has, and published most stringent limit on charged violating decay μ+→e+γ: BR(μ+→e+γ) <4.2×10−13 90% confidence level. detector has been upgraded order reach a sensitivity 6×10−14. basic principle II is achieve highest possible using full muon beam intensity (7×107...
Abstract The cylindrical drift chamber is the most innovative part of MEG II detector, upgraded version experiment. differs from one because it a single volume structure, instead segmented one, chosen to improve its resolutions and efficiency in detecting low energy positrons muon decays at rest. In this paper, we show characteristics performances fundamental apparatus discuss impact higher resolution on sensitivity Because structure high quality will be cornerstone development an ideal...
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...
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...
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...
A knob bow fibula (Bügelknopffibel) of the Leutkirch type, which typologically belongs to second half 4th and early 5th century CE, was excavated in 2018 Roman city Augusta Raurica, present-day Kaiseraugst (AG, Switzerland). This analyzed for first time its elemental composition by using non-destructive technique Muon Induced X-ray Emission (MIXE) continuous muon beam facility at Paul Scherrer Institute (PSI). In present work, detection limit is 0.4 wt% with ∼ 1.5 hours measurement time. The...
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...
Abstract We present the first direct search for lepton flavour violating muon decay mediated by a new light particle X, $$\upmu ^+ \rightarrow \mathrm {e}^+\mathrm {X}, {X} \upgamma \ $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msup> <mml:mi>μ</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo>→</mml:mo> <mml:mi>e</mml:mi> </mml:mrow> <mml:mi>X</mml:mi> <mml:mo>,</mml:mo> <mml:mi>γ</mml:mi> <mml:mspace /> </mml:math> . This uses dataset resulting from...
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...