A5085254586- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Dark Matter and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Computational Physics and Python Applications
- Gamma-ray bursts and supernovae
- Atmospheric chemistry and aerosols
- Atmospheric Ozone and Climate
- Muon and positron interactions and applications
- Superconducting Materials and Applications
- Astro and Planetary Science
- Particle Accelerators and Free-Electron Lasers
- CCD and CMOS Imaging Sensors
- Neutrino Physics Research
- Medical Imaging Techniques and Applications
- Particle accelerators and beam dynamics
- Radiation Effects in Electronics
- Astronomy and Astrophysical Research
- Atmospheric aerosols and clouds
- Black Holes and Theoretical Physics
- Astrophysics and Cosmic Phenomena
- Nuclear Physics and Applications
European Organization for Nuclear Research
2015-2024
Istituto Nazionale di Fisica Nucleare, Sezione di Bari
2006-2024
University of Bari Aldo Moro
2024
Université Claude Bernard Lyon 1
2021
Ibero American University
2020
Panjab University
2020
Institute of High Energy Physics
2012-2017
University of Leeds
2016
University of Beira Interior
2016
University of Lisbon
2016
Nucleation of aerosol particles from trace atmospheric vapours is thought to provide up half global cloud condensation nuclei. Aerosols can cause a net cooling climate by scattering sunlight and leading smaller but more numerous droplets, which makes clouds brighter extends their lifetimes. Atmospheric aerosols derived human activities are have compensated for large fraction the warming caused greenhouse gases. However, despite its importance climate, nucleation poorly understood. Recently,...
Abstract About half of present-day cloud condensation nuclei originate from atmospheric nucleation, frequently appearing as a burst new particles near midday 1 . Atmospheric observations show that the growth rate often accelerates when diameter is between one and ten nanometres 2,3 In this critical size range, are most likely to be lost by coagulation with pre-existing 4 , thereby failing form typically 50 100 across. Sulfuric acid vapour involved in nucleation but too scarce explain...
Abstract Atmospheric aerosols and their effect on clouds are thought to be important for anthropogenic radiative forcing of the climate, yet remain poorly understood 1 . Globally, around half cloud condensation nuclei originate from nucleation atmospheric vapours 2 It is that sulfuric acid essential initiate most particle formation in atmosphere 3,4 , ions have a relatively minor role 5 Some laboratory studies, however, reported organic without intentional addition acid, although...
Observations made in the CLOUD chamber at CERN illuminate atmospheric particle formation.
A list of authors and their affiliations appears at the end paper New-particle formation is a major contributor to urban smog1,2, but how it occurs in cities often puzzling3. If growth rates particles are similar those found cleaner environments (1-10 nanometres per hour), then existing understanding suggests that new should be rapidly scavenged by high concentration pre-existing particles. Here we show, through experiments performed under atmospheric conditions CLOUD chamber CERN, below...
Significance A mechanism for the formation of atmospheric aerosols via gas to particle conversion highly oxidized organic molecules is found be dominant aerosol process in preindustrial boundary layer over land. The inclusion this a global model raises baseline concentrations and could lead reduction 27% estimates anthropogenic radiative forcing.
Abstract We report comprehensive, demonstrably contaminant‐free measurements of binary particle formation rates by sulfuric acid and water for neutral ion‐induced pathways conducted in the European Organization Nuclear Research Cosmics Leaving Outdoor Droplets chamber. The recently developed Atmospheric Pressure interface‐time flight‐mass spectrometer was used to detect contaminants charged clusters identify runs free any contaminants. Four parameters were varied cover ambient conditions:...
Abstract The growth of freshly formed aerosol particles can be the bottleneck in their survival to cloud condensation nuclei. It is therefore crucial understand how grow atmosphere. Insufficient experimental data has impeded a profound understanding nano-particle under atmospheric conditions. Here we study CLOUD (Cosmics Leaving OUtdoors Droplets) chamber, starting from formation molecular clusters. We present measured rates at sub-3 nm sizes with different atmospherically relevant...
NO x is important for particle growth as it can participate in HOM formation and alter the volatility distribution.
Abstract New particle formation in the upper free troposphere is a major global source of cloud condensation nuclei (CCN) 1–4 . However, precursor vapours that drive process are not well understood. With experiments performed under tropospheric conditions CERN CLOUD chamber, we show nitric acid, sulfuric acid and ammonia form particles synergistically, at rates orders magnitude faster than those from any two three components. The importance this mechanism depends on availability ammonia,...
Dimethyl sulfide (DMS) influences climate via cloud condensation nuclei (CCN) formation resulting from its oxidation products (mainly methanesulfonic acid, MSA, and sulfuric H2SO4). Despite their importance, accurate prediction of MSA H2SO4 DMS remains challenging. With comprehensive experiments carried out in the Cosmics Leaving Outdoor Droplets (CLOUD) chamber at CERN, we show that decreasing temperature +25 to −10 °C enhances gas-phase production by an order magnitude OH-initiated...
The NA62 experiment at CERN SPS is designed to study the $K^+\to\pi^+\nu\bar\nu$ decay. After collecting data in 2016, 2017, and 2018, has resumed taking 2021 received approval for operations until onset of LS3. first search lepton number violating decay $K^+\to\pi^0\pi^-\mu^+ e^+$ flavour decays $K^+\to\pi^0\pi^+\mu^+ e^-$ , $K^+\to\pi^0\pi^+\mu^- reported. More recent results from analyses $K^+\to\pi^+\gamma\gamma$ $\pi^0\to e^+e^-$ are also Additionally, New Physics collected during...
Abstract. The CLOUD experiment (Cosmics Leaving OUtdoor Droplets) investigates the nucleation of new particles and how this process is influenced by galactic cosmic rays in an electropolished, stainless-steel environmental chamber at CERN (European Organization for Nuclear Research). Since volatile organic compounds (VOCs) can act as precursor gases growth particles, great efforts have been made to keep their unwanted background levels low possible quantify them. In order be able measure a...
CERN's Linac4 45 kV H− ion sources prototypes are installed at a dedicated source test stand and in the tunnel. The operation of pulsed hydrogen injection, RF sustained plasma, high voltages described. first experimental results two relying on 2 MHz RF-plasma heating presented. plasma is ignited via capacitive coupling, by inductive coupling. light emitted from collected viewports pointing to chamber wall middle solenoid axis. Preliminary measurements optical emission spectroscopy photometry...
CERN’s 160 MeV H− linear accelerator (Linac4) is a key constituent of the injector chain upgrade Large Hadron Collider that being installed and commissioned. A cesiated surface ion source prototype tested has delivered beam intensity 45 mA within an emittance 0.3 π ⋅ mm mrad. The optimum ratio co-extracted electron- to ion-current below 1 best production efficiency, defined as current 2 MHz RF-power transmitted plasma, reached 1.1 mA/kW. first tests new optics, electron-dump, front end...
Two volume sources equipped with DESY and CERN plasma generators a low voltage electron dump were operated at 45 kV in the Linac4 tunnel on dedicated test stand. These delivered approximately 20 mA ensured commissioning of Radio Frequency Quadrupole accelerator first section Drift Tube Linac. CERN's prototype cesiated surface source this was continuously from November 2013 to April 2014 ion stand is being commissioned tunnel. Before cesiation, conditioned mode provided up 30 H− beam. Short...
The large muon trigger systems based on Resistive Plate Chambers (RPC) at the LHC experiments are currently operated with R134a mixture. Unfortunately is considered a greenhouse gas high impact enviroment and therefore will be subject to regulations aiming in strongly reducing available quantity market. immediat effects might instability price incertitude product availability. Alternative gases (HFO-1234yf HFO-1234ze) have been already identified by industry for specific applications as...
Resistive Plate Chambers detectors are largely employed at the CERN LHC experiments thanks to their excellent trigger performances and contained costs. They operated with a gas mixture made of 90%–95% C2H2F4, that provides high number ion–electron pairs, about 5% i-C4H10, ensures suppression photon-feedback effects, 0.3% SF6, used as an electron quencher further operate detector in streamer-free mode. C2H2F4 is known be Greenhouse gas, global warming potential (GWP) 1430. has identified...
(Shortened) The Swift and HETE-2 discovery of an afterglow associated possibly with short GRBs opened the new problematic their nature classification. This has been further enhanced by GRB060614 observation a re-analysis BATSE catalog leading to identification GRB class "an occasional softer extended emission lasting tenths seconds after initial spikelike emission". We plan: a) fit this "hybrid" sources within our "canonical GRB" scenario, where all are generated "common engine" (i.e....