C. Malbrunot
A5012015924- Atomic and Molecular Physics
- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Atomic and Subatomic Physics Research
- Muon and positron interactions and applications
- Cold Atom Physics and Bose-Einstein Condensates
- Particle Detector Development and Performance
- Particle accelerators and beam dynamics
- Quantum Chromodynamics and Particle Interactions
- Neutrino Physics Research
- Radiation Detection and Scintillator Technologies
- High-Energy Particle Collisions Research
- Quantum, superfluid, helium dynamics
- Astrophysics and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Advanced Frequency and Time Standards
- Particle Accelerators and Free-Electron Lasers
- Advanced Chemical Physics Studies
- Quantum and Classical Electrodynamics
- Quantum Mechanics and Applications
- Nuclear physics research studies
- Plasma Diagnostics and Applications
- Physics of Superconductivity and Magnetism
- Computational Physics and Python Applications
- Superconducting and THz Device Technology
TRIUMF
2009-2025
European Organization for Nuclear Research
2015-2024
McGill University
2023-2024
Austrian Academy of Sciences
2013-2023
Stefan Meyer Institute for Subatomic Physics
2013-2023
Institute of Microelectronics
2023
Chinese Academy of Sciences
2023
Raman Research Institute
2022
Istituto Nazionale di Fisica Nucleare, Sezione di Padova
2022
University of British Columbia
2011-2021
Antihydrogen, a positron bound to an antiproton, is the simplest antiatom. Its counterpart—hydrogen—is one of most precisely investigated and best understood systems in physics research. High-resolution comparisons both provide sensitive tests CPT symmetry, which fundamental symmetry Standard Model elementary particle physics. Any measured difference would point violation thus new Here we report development antihydrogen source using cusp trap for in-flight spectroscopy. A total 80 atoms are...
A bstract This article describes BabyIAXO, an intermediate experimental stage of the International Axion Observatory (IAXO), proposed to be sited at DESY. IAXO is a large-scale axion helioscope that will look for axions and axion-like particles (ALPs), produced in Sun, with unprecedented sensitivity. BabyIAXO conceived test all subsystems (magnet, optics detectors) relevant scale final system thus serve as prototype IAXO, but same time fully-fledged physics reach itself, potential discovery....
A bstract We present results of the Relic Axion Dark-Matter Exploratory Setup (RADES), a detector which is part CERN Solar Telescope (CAST), searching for axion dark matter in 34.67 μ eV mass range. radio frequency cavity consisting 5 sub-cavities coupled by inductive irises took physics data inside CAST dipole magnet first time using this filter-like haloscope geometry. An exclusion limit with 95% credibility level on axion-photon coupling constant g aγ ≳ 4 × 10 − 13 GeV 1 over range 34 ....
Abstract Antihydrogen atoms with K or sub-K temperature are a powerful tool to precisely probe the validity of fundamental physics laws and design highly sensitive experiments needs antihydrogen controllable well defined conditions. We present here experimental results on production in pulsed mode which time when 90% produced is known an uncertainty ~250 ns. The source generated by charge-exchange reaction between Rydberg positronium atoms—produced via injection positron beam into...
The CAST-CAPP axion haloscope, operating at CERN inside the CAST dipole magnet, has searched for axions in 19.74 $\mu$eV to 22.47 mass range. detection concept follows Sikivie haloscope principle, where Dark Matter convert into photons within a resonator immersed magnetic field. is an array of four individual rectangular cavities inserted strong phase-matched maximize sensitivity. Here we report on data acquired 4124 h from 2019 2021. Each cavity equipped with fast frequency tuning mechanism...
A new measurement of the branching ratio R_{e/μ}=Γ(π^{+}→e^{+}ν+π^{+}→e^{+}νγ)/Γ(π^{+}→μ^{+}ν+π^{+}→μ^{+}νγ) resulted in R_{e/μ}^{exp}=[1.2344±0.0023(stat)±0.0019(syst)]×10^{-4}. This is agreement with standard model prediction and improves test electron-muon universality to level 0.1%.
A search for massive neutrinos has been made in the decay $\pi\rightarrow e^+ \nu$. No evidence was found extra peaks positron energy spectrum indicative of pion decays involving ($\pi\rightarrow \nu_h$). Upper limits (90 \% C.L.) on neutrino mixing matrix element $|U_{ei}|^2$ mass region 60--135 MeV/$c^2$ were set, which are %representing an order magnitude improvement over previous results.
Abstract The precise measurement of forces is one way to obtain deep insight into the fundamental interactions present in nature. In context neutral antimatter, gravitational interaction high interest, potentially revealing new that violate weak equivalence principle. Here we report on a successful extension tool from atom optics—the moiré deflectometer—for acceleration slow antiprotons. setup consists two identical transmission gratings and spatially resolving emulsion detector for...
We demonstrate the laser excitation of $n=3$ state positronium (Ps) in vacuum. A combination a specially designed pulsed slow positron beam and high-efficiency converter target was used to produce Ps. Its annihilation recorded by single-shot lifetime spectroscopy. Pulsed level at wavelength $\ensuremath{\lambda}\ensuremath{\approx}205$ nm monitored via Ps photoionization induced second intense pulse $\ensuremath{\lambda}=1064$ nm. About 15% overall emitted into vacuum excited photoionized....
We propose, design and construct a variant of the conventional axion haloscope concept that could be competitive in search for dark matter axions masses decade 10–100 μeV. Theses are located somewhat above mass range which existing experiments have reached sensitivity to benchmark QCD models. Our consists an array small microwave cavities connected by rectangular irises, arrangement commonly used radio-frequency filters. The size unit cavity determines main resonant frequency, while...
In the present work of PIENU experiment, heavy neutrinos were sought in pion decays π+→μ+ν at rest by examining observed muon energy spectrum for extra peaks addition to expected peak a light neutrino. No evidence was observed. Upper limits set on neutrino mixing matrix |Uμi|2 mass region 15.7–33.8 MeV/c2, improving previous results an order magnitude.
Evidence of massive neutrinos in the ${\ensuremath{\pi}}^{+}\ensuremath{\rightarrow}{e}^{+}\ensuremath{\nu}$ decay spectrum was sought with background ${\ensuremath{\pi}}^{+}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}\ensuremath{\rightarrow}{e}^{+}$ chain highly suppressed. Upper limits (90% C.L.) on neutrino mixing matrix element $|{U}_{ei}{|}^{2}$ mass region $60--129\text{ }\text{ }\mathrm{MeV}/{c}^{2}$ were set at level ${10}^{\ensuremath{-}8}$.
A bstract RADES (Relic Axion Detector Exploratory Setup) is a project with the goal of directly searching for axion dark matter above 30 μ eV scale employing custom-made microwave filters in magnetic dipole fields. Currently taking data at LHC CAST experiment. In long term, cavities are envisioned to take BabyIAXO magnet. this article we report on modelling, building and characterisation an optimised microwave-filter design alternating irises that exploits maximal coupling axions while being...
Abstract In the near future BabyIAXO will be most powerful axion helioscope, relying on a custom‐made magnet of two bores 70 cm diameter and 10 m long, with total available magnetic volume more than 7 3 . this document, it proposes describe implementation low‐frequency haloscope setups suitable for operation inside magnet. The RADES proposal has potential sensitivity to axion‐photon coupling down values corresponding KSVZ model, in (currently unexplored) mass range between 1 2 eV, after...
We describe a system designed to re-bunch positron pulses delivered by an accumulator supplied source and Surko-trap. Positron from the are magnetically guided in 0.085 T field injected into region free of magnetic fields through μ-metal terminator. Here positrons temporally compressed, electrostatically accelerated towards porous silicon target for production emission positronium vacuum. Positrons focused spot less than 4 mm FWTM bunches ∼8 ns FWHM. Emission vacuum is shown single shot...
The goal of the ASACUSA-CUSP collaboration at Antiproton Decelerator CERN is to measure ground-state hyperfine splitting antihydrogen using an atomic spectroscopy beamline. A milestone was achieved in 2012 through detection 80 atoms 2.7 m away from their production region. This first observation ‘cold’ a magnetic field free In parallel progress on production, beamline tested with source hydrogen. led measurement relative precision 2.7×10 −9 which constitutes most precise hydrogen beam....
The axion is a hypothetical particle which candidate for cold dark matter. Haloscope experiments directly search these particles in strong magnetic fields with RF cavities as detectors. Relic Axion Detector Exploratory Setup (RADES) at CERN particular searching matter mass range above 30 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mu$</tex-math></inline-formula> eV. figure of merit our detector depends...
Hypothetical axions provide a compelling explanation for dark matter and could be emitted from the hot solar interior. The CERN Axion Solar Telescope has been searching via their back conversion to x-ray photons in 9-T 10-m long magnet directed toward Sun. We report on an extended run with International Observatory pathfinder detector, doubling previous exposure time. detector was operated xenon-based gas mixture part of new run, providing technical insights future configurations. No counts...
Abstract Antihydrogen, the lightest atom consisting purely of antimatter, is an ideal laboratory to study CPT symmetry by comparison with hydrogen. With respect absolute precision, transitions within ground-state hyperfine structure (GS-HFS) are most appealing virtue their small energy separation. ASACUSA proposed employing a beam cold antihydrogen atoms in Rabi-type experiment, determine GS-HFS field-free region. Here we present measurement zero-field hydrogen using spectroscopy apparatus...
Positronium in the $2^{\phantom{\rule{0.16em}{0ex}}3}\mathrm{S}$ metastable state exhibits a low electrical polarizability and long lifetime (1140 ns), making it promising candidate for interferometry experiments with neutral matter-antimatter system. In present work, positronium is produced, absence of an electric field, via spontaneous radiative decay from $3^{\phantom{\rule{0.16em}{0ex}}3}\mathrm{P}$ level populated 205-nm UV laser pulse. Thanks to short temporal length pulse, 1.5 ns full...