R.S. Brusa
A5006190112- Muon and positron interactions and applications
- Atomic and Molecular Physics
- Graphene research and applications
- Particle Detector Development and Performance
- Semiconductor materials and devices
- Atomic and Subatomic Physics Research
- Dark Matter and Cosmic Phenomena
- Particle accelerators and beam dynamics
- Cold Atom Physics and Bose-Einstein Condensates
- Electron and X-Ray Spectroscopy Techniques
- Radiation Detection and Scintillator Technologies
- Copper Interconnects and Reliability
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced Chemical Physics Studies
- Ammonia Synthesis and Nitrogen Reduction
- Advancements in Battery Materials
- Ion-surface interactions and analysis
- Diamond and Carbon-based Materials Research
- Glass properties and applications
- Hydrogen Storage and Materials
- Quantum and Classical Electrodynamics
- Neutrino Physics Research
- Membrane Separation and Gas Transport
- Advanced Frequency and Time Standards
- Metal and Thin Film Mechanics
University of Trento
2016-2025
Istituto Nazionale di Fisica Nucleare, Trento Institute for Fundamental Physics And Applications
2016-2025
University of Oslo
2017
Istituto Nazionale di Fisica Nucleare
2011-2016
Moscow Engineering Physics Institute
2015
National Interuniversity Consortium for the Physical Sciences of Matter
2009-2014
ETH Zurich
2012
Politecnico di Milano
2011
Institute for Nuclear Research
2011
Istituto Nazionale di Fisica Nucleare, Sezione di Pavia
2011
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...
We report on laser cooling of a large fraction positronium (Ps) in free flight by strongly saturating the 1^{3}S-2^{3}P transition with broadband, long-pulsed 243 nm alexandrite laser. The ground state Ps cloud is produced magnetic and electric field-free environment. observe two different laser-induced effects. first effect an increase number atoms after time has spent long-lived 2^{3}P states. second one-dimensional Doppler Ps, reducing cloud's temperature from 380(20) to 170(20) K....
High formation yield and a meaningful cooled fraction of positronium below room temperature were obtained by implanting positrons in silicon target which well-controlled oxidized nanochannels (5--8 nm diameter) perpendicular to the surface produced. We show that at 7 keV held 150 K, about 27% form escapes into vacuum. Around 9% escaped is collision with walls emitted Maxwellian beam K. Because quantum confinement limits minimum achievable energy, tuning nanochannel's size crucial for...
The AEGIS experiment, currently being set up at the Antiproton Decelerator CERN, has objective of studying free fall antimatter in Earth's gravitational field by means a pulsed cold atomic beam antihydrogen atoms. Both duration and vertical displacement horizontally emitted atoms will be measured, allowing first test WEP with antimatter.
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....
Total cross sections for electron scattering have been measured in the 75--4000-eV energy range ${\mathrm{NH}}_{3}$, ${\mathrm{SiH}}_{4}$, and ${\mathrm{H}}_{2}$S. For these gases, as well ${\mathrm{CH}}_{4}$ ${\mathrm{H}}_{2}$O, fitted with a Born-like formula containing two parameters each gas. The high-energy parameter of fit to has related bond length molecules. Partitioning total into inelastic elastic gases is discussed on basis available experimental data.
A positron-positronium converter composed of regular nanochannels with size in the 5--100 nm range and length about $2\text{ }\ensuremath{\mu}\text{m}$ has been produced silicon by electrochemical etching. After controlled oxidation inner surface channels, a positronium yield up to 45% positrons implanted at 1 keV energy was observed. At positron implantation 42% is estimated be emitted into vacuum. 10 energy, corresponding depth $\ensuremath{\sim}800\text{ }\text{nm}$, fraction vacuum still...
Absolute total cross sections for electron -methane scattering have been measured in the energy range from 0.9 to 4000 eV two separate experiments. The present results, first available above 500 eV, are good agreement with other recent experimental and theoretical data. low is dominated by a shape resonance; broad hump has detected centred around 100 eV. A short critical review of previous measurements given.
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...
Abstract A powerful and robust control system is a crucial, often neglected, pillar of any modern, complex physics experiment that requires the management multitude different devices their precise time synchronisation. The AEḡIS collaboration presents CIRCUS, novel, autonomous optimised for time-critical experiments such as those at CERN’s Antiproton Decelerator and, more broadly, in atomic quantum research. Its setup based on Sinara/ARTIQ TALOS, integrating ALPACA analysis pipeline, last...
Antihydrogen formation at AEgIS CERN leverages charge exchange between Rydberg positronium (Ps*) and antiprotons, with cross-sections scaling the Ps principal quantum number $n^4$ inversely relative velocity $𝑣^{−2}$. However, motional Stark effect mismatch antiprotons impose stringent constraints, limiting efficiency. Advances in transmission converters mitigate self-ionization losses improve alignment, promising a significant boost antihydrogen yield. This work evaluates cross-sections,...
The experimental demonstration of positronium laser cooling with stationary broadband pulses negative detuning is briefly described. Considerations on the limits current experiment and possible future developments follow. In particular, benefit positron remoderation, use a magnetic field, polarization, pulse shaping, coherent deceleration are shortly discussed.
Primary goal of the AEḡIS experiment is to precisely measure free fall antihydrogen within Earth’s gravitational field. To this end, cold (≈50 K) will traverse a two-grid moiré deflectometer before annihilating onto position-sensitive detector, which shall determine vertical position annihilation vertex relative grids with micrometric accuracy. Here, we introduce vertexing detector based on modified mobile camera sensor and experimentally demonstrate that it can antiproton annihilations...
The depth profile of open volume defects has been measured in Si implanted with He at an energy 20 keV, by means a slow-positron beam and the Doppler broadening technique. evolution defect distributions studied as function isochronal annealing two series samples fluence $5\ifmmode\times\else\texttimes\fi{}{10}^{15}$ $2\ifmmode\times\else\texttimes\fi{}{10}^{16}{\mathrm{He}\mathrm{}\mathrm{cm}}^{\ensuremath{-}2}.$ A fitting procedure applied to experimental data extract positron parameter...
The total cross sections of chlorofluoromethane molecules were measured in the 75--4000-eV range. A comparison is given with existing experimental and theoretical data. present data previous measurements 15--50-eV range fitted a Born-like formula. This simple fit allows to be reproduced within errors. Phenomenological double Yukawa scattering potentials can derived from short discussion for total-cross-section partitioning ${\mathrm{CF}}_{4}$, ${\mathrm{CF}}_{2}$${\mathrm{Cl}}_{2}$,...
The main goal of the AEgIS experiment at CERN is to test weak equivalence principle for antimatter. will measure free-fall an antihydrogen beam traversing a moir\'e deflectometer. determine gravitational acceleration g with initial relative accuracy 1% by using emulsion detector combined silicon micro-strip time flight. Nuclear emulsions can annihilation vertex atoms precision about 1 - 2 microns r.m.s. We present here results detectors operated in vacuum low energy antiprotons from...
Positron annihilation lifetime spectroscopy is employed to measure the size of interstitial void spaces characterizing structure a set permanently densified ${\mathrm{SiO}}_{2}$ glasses. The average volume voids markedly affected by densification process and linearly shrinks almost an order magnitude after relative density variation 22%. In addition, x-ray diffraction shows that this change does not modify appreciably short range order, which remains organized in ${\mathrm{SiO}}_{4}$...
In this work we report on the systematic characterization of a rare-gas moderated magnetically-transported continuous positron beam based 22Na radioactive source. The was performed with three different solid moderators: Ne, Ar, and Kr. Each moderator deposited then thermal annealed at temperature ∼ 35 % 30 lower than melting point, respectively. Tests moderation/magnetic transport efficiency apparatus have shown maximum 1.8 10-3, 2.0 10-3 0.6 for Kr, average longitudinal kinetic energy...