P.-R. Kettle
A5056086544- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Atomic and Subatomic Physics Research
- Particle Detector Development and Performance
- Nuclear Physics and Applications
- High-Energy Particle Collisions Research
- Muon and positron interactions and applications
- Nuclear physics research studies
- Quantum, superfluid, helium dynamics
- Particle accelerators and beam dynamics
- Radiation Detection and Scintillator Technologies
- Black Holes and Theoretical Physics
- Atomic and Molecular Physics
- Particle Accelerators and Free-Electron Lasers
- Medical Imaging Techniques and Applications
- Astrophysics and Cosmic Phenomena
- Computational Physics and Python Applications
- Cosmology and Gravitation Theories
- Advanced biosensing and bioanalysis techniques
- Influenza Virus Research Studies
- Polyomavirus and related diseases
- Mass Spectrometry Techniques and Applications
- Radioactive Decay and Measurement Techniques
Paul Scherrer Institute
2013-2024
University of Freiburg
1978-2008
University of Coimbra
1999
Swiss Federal Nuclear Safety Inspectorate
1981-1987
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 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...
We have performed a search for admixtures of massive neutrinos in the pion decay ${\ensuremath{\pi}}^{+}$\ensuremath{\rightarrow}${\ensuremath{\mu}}^{+}$+\ensuremath{\nu} at Swiss Institute Nuclear Research (SIN). Positive pions were stopped high-purity germanium detector and energy their muons was measured with resolution 10 keV (full width half maximum). The spectrum searched additional peaks, existence which would indicated lepton mixing; no such peaks found. upper limit branching ratio...
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...
We have studied the time-of-flight spectra of neutrons produced by charge-exchange reaction ${\ensuremath{\pi}}^{\ensuremath{-}}p\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}n$ ${\ensuremath{\pi}}^{\ensuremath{-}}p$ atoms in liquid hydrogen, at flight distances up to 18.1 m. found neutron velocity for rest be 0.894 266\ifmmode\pm\else\textpm\fi{}0.000 063 cm/ns, corresponding a pion mass difference...
Currently, PSI delivers the most intense continuous muon beam in world with up to a few 10 8 µ + /s. The High-Intensity Muon Beams (HIMB) project is developing new target station and beamlines able deliver /s, huge impact for low-energy, high-precision experiments. While next generation of proton drivers powers excess currently achieved 1.4 MW still require significant research development, focus HIMB improve surface yield geometry increase capture transmission solenoid-based beamline order...
Meson factories are powerful drivers of diverse physics programs. With beam powers already in the MW-regime attention has to be turned target and line design further significantly increase surface muon rates available for experiments. For this reason we have explored possibility using a neutron spallation as source muons by performing detailed Geant4 simulations with pion production cross sections based on parametrization existing data. While outperforms standard targets backward direction...
Results from neutrino mass and oscillation experiments now set the of muon to less than 2 eV/c2. This fact, together with our former measurement momentum in pion decay at rest, pμ+=(29.79200±0.00011) MeV/c, allows us directly determine charged 1 ppm precision which constitutes most precise value date, mπ+=(139.57021±0.00014)MeV/c2. is within 1.44 σ Particle Data Group's compilation value, mπ±=(139.57061±0.00024) MeV/c2. From pμ+ we derive kinetic energy muon, Tμ+=(4.11984±0.00003) MeV...
Positive pions were stopped in a Ge detector and the energy of their decay muons was measured with resolution 6.7 keV. The spectrum analyzed to obtain an upper limit for branching ratio into muon heavy neutrino. For neutrino masses between 2.5 10 MeV/${\mathit{c}}^{2}$ this is few parts ${10}^{4}$.
The Mu3e experiment searches for charged lepton flavor violation in the rare decay μ→eee with a projected sensitivity of 10−16. A precise measurement product momenta, vertex and time is necessary background suppression at rates 109 muons/s. This can be achieved by combining an ultra-lightweight pixel tracker based on HV-MAPS two timing systems. trigger-less readout detector three stages FPGA-boards over multi GBit/s optical links into GPU filter farm presented. In this scheme data from all...
The time-dependent rate asymmetry of initial K0 and decaying into π+π−π0 was measured in order to reveal the CP-violating amplitude KS → decay. For real imaginary parts η+−0, we find Re(η+−0) = (6 ± 13stat. 1syst.) × 10−3 Im(η+−0) (−2 18stat. 3syst.) which correspond |η+−0| < 0.037 with CL.