H. Benmansour
A5024409064- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- Neutrino Physics Research
- Quantum Chromodynamics and Particle Interactions
- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Nuclear Physics and Applications
- Magnetic confinement fusion research
- Nuclear reactor physics and engineering
- Radiation Therapy and Dosimetry
- Muon and positron interactions and applications
- Astrophysics and Cosmic Phenomena
- Atmospheric chemistry and aerosols
- Spectroscopy and Laser Applications
- Atmospheric Ozone and Climate
- Distributed and Parallel Computing Systems
- Graphite, nuclear technology, radiation studies
- Synthesis and properties of polymers
- Dendrimers and Hyperbranched Polymers
- Advanced Frequency and Time Standards
- Superconducting Materials and Applications
- Advanced Polymer Synthesis and Characterization
University of Pisa
2022-2024
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa
2022-2024
Queen's University
2021-2022
Paul Scherrer Institute
2022
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...
Dark matter with Planck-scale mass (≃10^{19} GeV/c^{2}) arises in well-motivated theories and could be produced by several cosmological mechanisms. A search for multiscatter signals from supermassive dark was performed a blind analysis of data collected over 813 d live time DEAP-3600, 3.3 t single-phase liquid argon-based detector at SNOLAB. No candidate were observed, leading to the first direct detection constraints on matter. Leading limits constrain masses between 8.3×10^{6} 1.2×10^{19}...
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...
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...
Abstract The DEAP-3600 detector searches for the scintillation signal from dark matter particles scattering on a 3.3 tonne liquid argon target. largest background comes $$^{39}\text{ Ar }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msup> <mml:mrow/> <mml:mn>39</mml:mn> </mml:msup> <mml:mspace/> <mml:mtext>Ar</mml:mtext> </mml:mrow> </mml:math> beta decays and is suppressed using pulse-shape discrimination (PSD). We use two types of PSD estimator:...
The MEG II experiment, based at the Paul Scherrer Institut in Switzerland, reports result of a search for decay $\mu^+\to e^+\gamma$ from data taken first physics run 2021. No excess events over expected background is observed, yielding an upper limit on branching ratio B($\mu^+\to e^+\gamma$) < $7.5 \times 10^{-13}$ (90% C.L.). combination this and obtained by gives $3.1 C.L.), which most stringent to date. A ten-fold larger sample being collected during years 2022-2023, data-taking will...
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 mu+ -> e+ gamma decay down 6e-14 almost an order magnitude better than current limit. In this paper, we describe operation and performance experiment give a new estimate its versus acquisition time.
The cylindrical drift chamber is the most innovative part of MEG~II detector, upgraded version MEG 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 tracking...
We present the ongoing development of an algorithm for software alignment MEG II drift chamber based on MillePede global approach. This method uses cosmic rays data collected during 2022 taking period to perform wire-by-wire alignment. discuss first results obtained data.
The observation of a resonance structure in the opening angle electron-positron pairs $^{7}$Li(p,\ee) $^{8}$Be reaction was claimed and interpreted as production subsequent decay hypothetical particle (X17). Similar excesses, consistent with this particle, were later observed processes involving $^{4}$He $^{12}$C nuclei same experimental technique. MEG II apparatus at PSI, designed to search for $\mu^+ \rightarrow \mathrm{e}^+ \gamma$ decay, can be exploited investigate existence study its...
Abstract In liquid argon-based particle detectors, slow wavelength shifters (WLSs) could be used alongside the common, nanosecond scale, WLS tetraphenyl butadiene (TPB) for background mitigation purposes. At room temperature, pyrene has a moderate fluorescence light yield (LY) and time constant of order hundreds nanoseconds. this work, four pyrene-doped polystyrene films with various purities concentrations were characterized in terms LY decay constants range temperature between 4 K 300...
The ultra-low mass cylindrical drift chamber designed for the MEG II experiment is a challenging apparatus made of 1728 phi = 20 micron gold plated tungsten sense wires, 7680 40 and 2496 50 silver aluminum field wires. Because electrostatic stability requirements all wires have to be stretched at mechanical tensions about 25, 19 29 g respectively which must controlled level better than 0.5 g. This presently in acquisition, but during its construction 100 broke, because chemical corrosion...