I. P. J. Shipsey
A5081503642- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Computational Physics and Python Applications
- Neutrino Physics Research
- Atomic and Subatomic Physics Research
- Cosmology and Gravitation Theories
- Medical Imaging Techniques and Applications
- Radiation Detection and Scintillator Technologies
- Particle Accelerators and Free-Electron Lasers
- CCD and CMOS Imaging Sensors
- Astrophysics and Cosmic Phenomena
- Black Holes and Theoretical Physics
- Superconducting Materials and Applications
- Distributed and Parallel Computing Systems
- Photocathodes and Microchannel Plates
- Electron and X-Ray Spectroscopy Techniques
- Radioactive Decay and Measurement Techniques
- Cold Atom Physics and Bose-Einstein Condensates
- Algorithms and Data Compression
- Advanced Electron Microscopy Techniques and Applications
- International Science and Diplomacy
- Nuclear physics research studies
University of Oxford
2016-2025
Science Oxford
2024
The University of Adelaide
2018-2023
University of Geneva
2023
University of Edinburgh
1988-2022
Heidelberg University
2021
SLAC National Accelerator Laboratory
2020
European Organization for Nuclear Research
2012-2020
Institute of High Energy Physics
2010-2017
Purdue University West Lafayette
2007-2016
We have measured the inclusive $b\ensuremath{\rightarrow}s\ensuremath{\gamma}$ branching ratio to be $(2.32\ifmmode\pm\else\textpm\fi{}0.57\ifmmode\pm\else\textpm\fi{}0.35)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$, where first error is statistical and second systematic. Upper lower limits on ratio, each at 95% C.L., are $B(b\ensuremath{\rightarrow}s\ensuremath{\gamma})<4.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$...
We have observed the decays ${\mathit{B}}^{0}$\ensuremath{\rightarrow}${\mathit{K}}^{\mathrm{*}}$(892${)}^{0}$\ensuremath{\gamma} and ${\mathit{B}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${\mathit{K}}^{\mathrm{*}}$(892${)}^{\mathrm{\ensuremath{-}}}$\ensuremath{\gamma}, which are evidence for quark-level process b\ensuremath{\rightarrow}s\ensuremath{\gamma}. The average branching fraction is...
We outline the experimental concept and key scientific capabilities of AION (Atom Interferometer Observatory Network), a proposed programme using cold strontium atoms to search for ultra-light dark matter, explore gravitational waves in mid-frequency range between peak sensitivities LISA LIGO/Virgo/ KAGRA/INDIGO/Einstein Telescope/Cosmic Explorer experiments, probe other frontiers fundamental physics. would complement planned searches as well mergers involving intermediate-mass black holes...
The double ratio R of the relative decay rates short- and long-lived neutral kaons into two charged pions was measured to be 0.980±0.004±0.005. deviation from CP violation in transition CP-odd K2 with ϵ′/ϵ=(3.3 ± 1.1)×10−3.
We report the first evidence of charmless semileptonic decays B mesons. In momentum interval 2.4–2.6 GeV/c where background from b→clν is negligible, average measured b→ueν and b→uμν partial branching ratios ΔBub(2.4,2.6) =(1.8±0.4±0.3)×10−4. Inclusion data 2.2–2.4 GeV/c, lepton yield dominated by b→clν, gives ΔBub(2.2,2.6) =(3.3±0.8±0.8)×10−4. ‖Vub/Vcb‖ depends on theoretical model b→ulν decay approximately 0.1.Received 8 November 1989DOI:https://doi.org/10.1103/PhysRevLett.64.16©1990...
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...
We present the first measurement of D*+ width using 9/fb e+ e- data collected near Upsilon(4S) resonance by CLEO II.V detector. Our method uses advanced tracking techniques and a reconstruction that takes advantage small vertical size CESR beam spot to measure energy release distribution from -> D0 pi+ decay. find Gamma(D*+) = 96 +- 4 (Statistical) 22 (Systematic) keV. also in decay compute Delta m m(D*+) - m(D0) 145.412 0.002 0.012 MeV/c^2
Using 13.5 inverse fb of e+e- annihilation data collected with the CLEO II detector we have observed a narrow resonance in Ds*+pi0 final state, mass near 2.46 GeV. The search for such state was motivated by recent discovery BaBar Collaboration at 2.32 GeV, DsJ*(2317)+ that decays to Ds+pi0. Reconstructing Ds+pi0 and states data, observe peaks both corresponding reconstructed difference distributions, dM(Dspi0)=M(Dspi0)-M(Ds) dM(Ds*pi0)=M(Ds*pi0)-M(Ds*), them values 350 MeV. We interpret...
In this paper we report quantitative measurements of the imaging performance for current generation hybrid pixel detector, Medipix3, used as a direct electron detector. We have measured modulation transfer function and detective quantum efficiency at beam energies 60 80keV. single mode, energy threshold values can be chosen to maximize either or efficiency, obtaining near to, exceeding those theoretical detector with square pixels. The Medipix3 charge summing mode delivers simultaneous, high...
We have fully reconstructed decays of both B0 and B- Mesons into final states containing either D, D*, D**, Psi, Psi', or Chi_{c1} mesons. This allows us to obtain new results on many physics topics including branching ratios, tests the factorization hypothesis, color suppression, resonant substructure, - mass difference.
We report on the observation of ηc′(2S01), radial excitation ηc(1S01) ground state charmonium, in two-photon fusion reaction γγ→ηc′→KS0K±π∓ 13.6 fb−1 CLEO II/II.V data and 13.1 III data. obtain M(ηc′)=3642.9±3.1(stat)±1.5(syst) MeV M(ηc)=2981.8±1.3(stat)±1.5(syst) MeV. The corresponding values hyperfine splittings between S01 S13 states are ΔMhf(1S)=115.1±2.0 ΔMhf(2S)=43.1±3.4 Assuming that ηc ηc′ have equal branching fractions to KSKπ, we Γγγ(ηc′)=1.3±0.6 keV.Received 23 December...
We report a measurement of the ${\mathit{D}}^{\mathrm{*}+}$ and ${\mathit{D}}^{\mathrm{*}0}$ decay branching fractions based on 780 ${\mathrm{pb}}^{\mathrm{\ensuremath{-}}1}$ data collected with CLEO II detector. For radiative decay, we obtain an upper limit, scrB(${\mathit{D}}^{\mathrm{*}+}$\ensuremath{\rightarrow}${\mathit{D}}^{+}$\ensuremath{\gamma})4.2% (90% confidence level), which is substantially below previous results, eliminates need for anomalously large charm quark magnetic moment.
We present new exclusion bounds obtained at the European X-Ray Free Electron Laser facility (EuXFEL) on axionlike particles in mass range 10^{-3} eV≲m_{a}≲10^{4} eV. Our experiment exploits Primakoff effect via which photons can, presence of a strong external electric field, decay into axions, then convert back after passing through an opaque wall. While similar searches have been performed previously third-generation synchrotron [Yamaji et al., Phys. Lett. B 782, 523...
Using data collected by the CLEO II detector, we have observed two states decaying to ${\ensuremath{\Lambda}}_{c}^{+}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$. Relative ${\ensuremath{\Lambda}}_{c}^{+}$, their mass splittings are measured be $+307.5\ifmmode\pm\else\textpm\fi{}0.4\ifmmode\pm\else\textpm\fi{}1.0$ and $+342.2\ifmmode\pm\else\textpm\fi{}0.2\ifmmode\pm\else\textpm\fi{}0.5\mathrm{MeV}{/c}^{2}$, respectively; this represents first measurement of less massive state....
Using a sample of $2.6\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $\ensuremath{\Upsilon}(4\mathrm{S})\ensuremath{\rightarrow}B\overline{B}$ events collected with the CLEO II detector at Cornell Electron Storage Ring, we have measured form factors for ${\overline{B}}^{0}\ensuremath{\rightarrow}{D}^{*+}{\ensuremath{\ell}}^{\ensuremath{-}}\overline{\ensuremath{\nu}}$. We perform three-parameter fit joint distribution four kinematic variables to obtain form-factor ratios...
We report on determinations of |Vub| resulting from studies the branching fraction and q^2 distributions in exclusive semileptonic B decays that proceed via b->u transition. Our data set consists 9.7x10^6 BBbar meson pairs collected at Y(4S) resonance with CLEO II detector. measure B(B0 -> pi- l+ nu) = (1.33 +- 0.18 0.11 0.01 0.07)x10^{-4} rho- (2.17 0.34 +0.47/-0.54 0.41 0.01)x10^{-4}, where errors are statistical, experimental systematic, systematic due to residual form-factor...
We review the current status of flavor-changing neutral currents in charm sector. focus on standard-model predictions and identify main sources theoretical uncertainties both [Formula: see text] mixing rare decays. The potential these observables for constraining short-distance physics standard model its extensions is compromised by presence large nonperturbative effects. examine possible discovery windows which can be tested study effects various to model. experimental situation future...
We present the first evidence for production of $\ensuremath{\Upsilon}(1D)$ states in four-photon cascade, $\ensuremath{\Upsilon}(3S)\ensuremath{\rightarrow}\ensuremath{\gamma}{\ensuremath{\chi}}_{b}(2P),$ ${\ensuremath{\chi}}_{b}(2P)\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\Upsilon}(1D),$ $\ensuremath{\Upsilon}(1D)\ensuremath{\rightarrow}\ensuremath{\gamma}{\ensuremath{\chi}}_{b}(1P),$...
We have studied hadronic decays of B mesons. report measurements exclusive branching ratios several charm decay modes mesons to final states with a D or D∗ and one three charged pions ρ ψ ψ′, kaon, up two pions. also measured inclusive for the spectra these particles in decays. The total content is found be (101±12)%. are compared form-factor models. extract parameters a1 a2 model Bauer, Stech, Wirbel DS constant. masses ¯B0 B− measured. mass difference between -0.4±0.6±0.5 MeV/c2.Received...
We report new measurements of the branching fractions B(B−→D0l−¯ν), B(¯B0→D+l−¯ν), and B(B−→D*0l−¯ν). Combining these results with our previous measurement B(¯B0→D*+l−¯ν), we find that ratio semileptonic widths for final states a vector meson pseudoscalar is (2.6+1.1+1.0−0.6−0.8) charged- to neutral-B-meson lifetimes (0.89±0.19±0.13)(f00f+−) where (f00f+−) neutral- charged-B-meson production at Υ(4S). From ¯B→Dl−¯ν fraction, calculate |Vcb|=0.040±0.006±0.006, first error statistical second...
This paper outlines the centralized design and production of ultra-high-vacuum sidearm laser-stabilization systems for AION Ultra-Cold Strontium Laboratories. Commissioning data on residual gas steady-state pressures in chambers, magnetic field quality, laser stabilization, loading rate 3D magneto-optical trap are presented. Streamlining stabilization enabled Collaboration to build equip parallel five state-of-the-art Laboratories within 24 months by leveraging key expertise collaboration....
The detection of low energy neutrinos ($<$ few tens MeV) via coherent nuclear scattering remains a holy grail sorts in neutrino physics. This uncontroversial mode interaction is expected to profit from sizeable increase cross section proportional neutron number squared the target nucleus, an advantageous feature view small probability all other channels this region. A detector would open door many new applications, ranging study fundamental properties true "neutrino technology"....