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G. Mazzitelli

Publications and source records attributed to G. Mazzitelli.

At least 37 records · Page 2Linked to original sources

First evidence of luminescence in a He/CF$_4$ gas mixture induced by non-ionizing electrons

Optical readout of Gas Electron Multipliers (GEM) provides very interesting performances and has been proposed for different applications in particle physics. In particular, thanks to its good efficiency in the keV energy range, it is being developed for low-energy and rare event studies, such as Dark Matter search. So far, the optical approach exploits the light produced during the avalanche processes in GEM channels. Further luminescence in the gas can be induced by electrons accelerated by a suitable electric field. The CYGNO collaboration studied this process with a combined use of a triple-GEM structure and a grid in an He/CF$_4$ (60/40) gas mixture at atmospheric pressure. Results reported in this paper allow to conclude that with an electric field of about 11~kV/cm a photon production mean free path of about 1.0~cm was found.

physics.ins-det↗

A 1 m$^3$ Gas Time Projection Chamber with Optical Readout for Directional Dark Matter Searches: the CYGNO Experiment

The aim of the CYGNO project is the construction and operation of a 1~m$^3$ gas TPC for directional dark matter searches and coherent neutrino scattering measurements, as a prototype toward the 100-1000~m$^3$ (0.15-1.5 tons) CYGNUS network of underground experiments. In such a TPC, electrons produced by dark-matter- or neutrino-induced nuclear recoils will drift toward and will be multiplied by a three-layer GEM structure, and the light produced in the avalanche processes will be readout by a sCMOS camera, providing a 2D image of the event with a resolution of a few hundred micrometers. Photomultipliers will also provide a simultaneous fast readout of the time profile of the light production, giving information about the third coordinate and hence allowing a 3D reconstruction of the event, from which the direction of the nuclear recoil and consequently the direction of the incoming particle can be inferred. Such a detailed reconstruction of the event topology will also allow a pure and efficient signal to background discrimination. These two features are the key to reach and overcome the solar neutrino background that will ultimately limit non-directional dark matter searches.

physics.ins-det↗

CYGNO: Triple-GEM Optical Readout for Directional Dark Matter Search

CYGNO is a project realising a cubic meter demonstrator to study the scalability of the performance of the optical approach for the readout of large-volume, GEM-equipped TPC. This is part of the CYGNUS proto-collaboration which aims at constructing a network of underground observatories for directional Dark Matter search. The combined use of high-granularity sCMOS and fast sensors for reading out the light produced in GEM channels during the multiplication processes was shown to allow on one hand to reconstruct 3D direction of the tracks, offering accurate energy measurements and sensitivity to the source directionality and, on the other hand, a high particle identification capability very useful to distinguish nuclear recoils. Results of the performed R&D and future steps toward a 30-100 cubic meter experiment will be presented.

physics.ins-det↗

CYGNO: a CYGNUs Collaboration 1 m^3 Module with Optical Readout for Directional Dark Matter Search

The design of the project named CYGNO is presented. CYGNO is a new proposal supported by INFN, the Italian National Institute for Nuclear Physics, within CYGNUs proto-collaboration (CYGNUS-TPC) that aims to realize a distributed observatory in underground laboratories for directional Dark Matter (DM) search and the identification of the coherent neutrino scattering (CNS) from the Sun. CYGNO is one of the first prototypes in the road map to 100-1000 m^3 of CYGNUs and will be located at the National Laboratory of Gran Sasso (LNGS), in Italy, aiming to make significant advances in the technology of single phase gas-only time projection chambers (TPC) for the application to the detection of rare scattering events. In particular it will focus on a read-out technique based on Micro Pattern Gas Detector (MPGD) amplification of the ionization and on the visible light collection with a sub-mm position resolution sCMOS (scientific COMS) camera. This type of readout - in conjunction with a fast light detection - will allow on one hand to reconstruct 3D direction of the tracks, offering accurate sensitivity to the source directionality and, on the other hand, a high particle identification capability very useful to distinguish nuclear recoils.

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The Scientists' Experience in Participated Science Communication

Since 2006 a small group of researchers from the Italian National Institute for Nuclear Physics started to realized one of the first European Researchers' Night in Europe: a one night-event, supported by the European Commission, that falls every last Friday of September to promote the researcher's figure and its work. Today, after thirteen editions, the project has evolved by involving more than 60 scientific partners and more than 400 events/year spread from the North to the South of Italy in 30 cities, captivating more than 50.000 attendees with a not negligible impact on the people and the press. During the years, the project has followed and sometimes anticipated the science communication trend, and BEES (BE a citizEn Scientist) is the last step of this long and thrilling evolution that brought to a huge public engagement in our territory. The experience, the methodology, and the major successful examples of the organized events are presented together with the results of the long term project impact.

physics.ed-ph↗

Physically Impossible?

Halfway between the experiment and the focus group, between the quiz and a game, we have experienced a new format to "focus" on sustainability and the fundamental laws of thermodynamics and its principles. Concepts as reversibility, efficiency and entropy, are then "visualized" by the participants, showing the relations with the economic value, waste, the energetics budget and raw material costs are explained from a different point of view, proving the physical limits to the economic growth and the environmental exploitation.

physics.ed-ph↗

Performance of Optically Readout GEM-based TPC with a 55Fe source

Optical readout of large Time Projection Chambers (TPCs) with multiple Gas Electron Multipliers (GEMs) amplification stages has shown to provide very interesting performances for high energy particle tracking. Proposed applications for low-energy and rare event studies, such as Dark Matter search, ask for demanding performance in the keV energy range. The performance of such a readout was studied in details as a function of the electric field configuration and GEM gain by using a $^{55}$Fe source within a 7 litre sensitive volume detector developed as a part of the R\&D for the CYGNUS project. Results reported in this paper show that the low noise level of the sensor allows to operate with a 2~keV threshold while keeping a rate of fake-events lesser than 10 per year. In this configuration, a detection efficiency well above 95\% along with an energy resolution ($σ$) of 18\% is obtained for the 5.9 keV photons, demonstrating the very promising capabilities of this technique.

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12 Years of Data, Results and Experiences in the European Researchers' Night Project

Since twelve years the researchers of the Roman area organize the European Researchers' Night, a project funded by European Commission to discover science and meet researchers through an Europe-wide public event dedicated to fun learning. Since the first edition in 2006, when the National Laboratory of INFN's in Frascati hosted 4000 visitors the project is always grown up to 50,000 attendees and more than 50 scientific partners. In the last edition, The Frascati Scienza association, which was born to coordinate the event, operated in over 30 Italian cities from south to north of the peninsula. In addition, the Made in Science project - European Research Week 2016/17 - has been the one of the largest project funded by the European Commission and it's often referred to as a model for organization and communication to the general public. The 12 yeas data collected and results obtained, as well as some of the most important experiences in public communication of science will be shown.

physics.ed-ph↗

Results From Impact Assessment on Society and scientists of Frascati Scienza European Researchers' Night in Years 2006-2015

The aim of this paper is to present the impact achieved by Frascati Scienza Association on society and research through the European Researchers' Night project funded by the European Commission within the years 2006-2015. The project has been devoted to raise awareness of researchers' work, encourage the dialogue between researchers and citizens and the choice of young people to pursue a career in science. The first scientific activities and cultural events took shape in 2006, under the coordination of the National Institute for Nuclear Physics (INFN), through the European Researchers' Night project, the most important and significant event to promote the role of the researcher and bring people of all ages closer to the scientific world. The positive and successful experience of the first two events, pushed the researchers and citizens of Frascati, where most of Italian research centers and infrastructures are located, to formally associate in the Frascati Scienza in 2008, who started to coordinate the event from 2008. Frascati Scienza was driven by the need to promote educational activities to citizens, young people and schools, in order to involve the general public in science and to bring researchers closer to society.

physics.ed-ph↗

MPGD Optical Read Out for Directional Dark Matter Search

The Time Projection method is an ideal candidate to track low energy release particles. Large volumes can be readout by means of a moderate number of channels providing a complete 3D reconstruction of the charged tracks within the sensitive volume. It allows the measurement not only of the total released energy but also of the energy release density along the tracks that can be very useful for particle identification and to solve the head-tail ambiguity of the tracks. Moreover, gas represents a very interesting target to study Dark Matter interactions. In gas, nuclear recoils can travel enough to give rise to tracks long enough to be acquired and reconstructed.

physics.ins-det↗

PTOLEMY: A Proposal for Thermal Relic Detection of Massive Neutrinos and Directional Detection of MeV Dark Matter

We propose to achieve the proof-of-principle of the PTOLEMY project to directly detect the Cosmic Neutrino Background (CNB). Each of the technological challenges described in [1,2] will be targeted and hopefully solved by the use of the latest experimental developments and profiting from the low background environment provided by the LNGS underground site. The first phase will focus on the graphene technology for a tritium target and the demonstration of TES microcalorimetry with an energy resolution of better than 0.05 eV for low energy electrons. These technologies will be evaluated using the PTOLEMY prototype, proposed for underground installation, using precision HV controls to step down the kinematic energy of endpoint electrons to match the calorimeter dynamic range and rate capabilities. The second phase will produce a novel implementation of the EM filter that is scalable to the full target size and which demonstrates intrinsic triggering capability for selecting endpoint electrons. Concurrent with the CNB program, we plan to exploit and develop the unique properties of graphene to implement an intermediate program for direct directional detection of MeV dark matter [3,4]. This program will evaluate the radio-purity and scalability of the graphene fabrication process with the goal of using recently identified ultra-high radio-purity CO2 sources. The direct detection of the CNB is a snapshot of early universe dynamics recorded by the thermal relic neutrino yield taken at a time that predates the epochs of Big Bang Nucleosynthesis, the Cosmic Microwave Background and the recession of galaxies (Hubble Expansion). Big Bang neutrinos are believed to have a central role in the evolution of the Universe and a direct measurement with PTOLEMY will unequivocally establish the extent to which these predictions match present-day neutrino densities.

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The AMY (Air Microwave Yield) experiment to measure the GHz emission from air shower plasma

The aim of the Air Microwave Yield (AMY) experiment is to investigate the Molecular Bremsstrahlung Radiation (MBR) emitted from an electron beam induced air-shower. The measurements have been performed with a 510 MeV electron beam at the Beam Test Facility (BTF) of Frascati INFN National Laboratories in a wide frequency range between 1 and 20 GHz. We present the experimental apparatus and the first results of the measurements. Contrary to what have been reported in a previous similar experiment~\cite{Gorham-SLAC}, we have found that the intensity of the emission is strongly influenced by the particular time structure of the accelerator beam. This makes very difficult the interpretation of the emission process and a realistic extrapolation of the emission yield to the plasma generated during the development of an atmospheric shower.

astro-ph.IM↗

Calibration of AGILE-GRID with on-ground data and Monte Carlo simulations

AGILE is a mission of the Italian Space Agency (ASI) Scientific Program dedicated to gamma-ray astrophysics, operating in a low Earth orbit since April 23, 2007. It is designed to be a very light and compact instrument, capable of simultaneously detecting and imaging photons in the 18 keV to 60 keV X-ray energy band and in the 30 MeV{50 GeV gamma-ray energy with a good angular resolution (< 1 deg at 1 GeV). The core of the instrument is the Silicon Tracker complemented with a CsI calorimeter and a AntiCoincidence system forming the Gamma Ray Imaging Detector (GRID). Before launch, the GRID needed on-ground calibration with a tagged gamma-ray beam to estimate its performance and validate the Monte Carlo simulation. The GRID was calibrated using a tagged gamma-ray beam with energy up to 500 MeV at the Beam Test Facilities at the INFN Laboratori Nazionali di Frascati. These data are used to validate a GEANT3 based simulation by comparing the data and the Monte Carlo simulation by measuring the angular and energy resolutions. The GRID angular and energy resolutions obtained using the beam agree well with the Monte Carlo simulation. Therefore the simulation can be used to simulate the same performance on-light with high reliability.

astro-ph.IM↗

Negative ion Time Projection Chamber operation with SF$_{6}$ at nearly atmospheric pressure

We present measurements of drift velocities and mobilities of some innovative negative ion gas mixtures at nearly atmospheric pressure based on SF$_{6}$ as electronegative capture agent and of pure SF$_{6}$ at various pressures, performed with the NITEC detector. NITEC is a Time Projection Chamber with 5 cm drift distance readout by a GEMPix, a triple thin GEMs coupled to a Quad-Timepix chip, directly sensitive to the deposited charge on each of the 55 $\times$ 55 $μ$m$^2$ pixel. Our results contribute to expanding the knowledge on the innovative use of SF$_{6}$ as negative ion gas and extend to triple thin GEMs the possibility of negative ion operation for the first time. Above all, our findings show the feasibility of negative ion operation with He:CF$_4$:SF$_{6}$ at 610 Torr, opening extremely interesting possibility for next generation directional Dark Matter detectors at 1 bar.

physics.ins-det↗

Carbon nanotubes as target for directional detection of light WIMP

In this paper I will briefly introduce the idea of using Carbon Nanotubes (CNT) as target for the detection of low mass WIMPs with the additional information of directionality. I will also present the experimental efforts of developing a Time Projection Chamber with a CNT target inside and the results of a test beam at the Beam Test Facility of INFN-LNF.

physics.ins-det↗

Technical Design Report EuroGammaS proposal for the ELI-NP Gamma beam System

The machine described in this document is an advanced Source of up to 20 MeV Gamma Rays based on Compton back-scattering, i.e. collision of an intense high power laser beam and a high brightness electron beam with maximum kinetic energy of about 720 MeV. Fully equipped with collimation and characterization systems, in order to generate, form and fully measure the physical characteristics of the produced Gamma Ray beam. The quality, i.e. phase space density, of the two colliding beams will be such that the emitted Gamma ray beam is characterized by energy tunability, spectral density, bandwidth, polarization, divergence and brilliance compatible with the requested performances of the ELI-NP user facility, to be built in Romania as the Nuclear Physics oriented Pillar of the European Extreme Light Infrastructure. This document illustrates the Technical Design finally produced by the EuroGammaS Collaboration, after a thorough investigation of the machine expected performances within the constraints imposed by the ELI-NP tender for the Gamma Beam System (ELI-NP-GBS), in terms of available budget, deadlines for machine completion and performance achievement, compatibility with lay-out and characteristics of the planned civil engineering.

physics.acc-ph↗

Tau/Charm Factory Accelerator Report

The present Report concerns the current status of the Italian Tau/Charm accelerator project and in particular discusses the issues related to the lattice design, to the accelerators systems and to the associated conventional facilities. The project aims at realizing a variable energy Flavor Factory between 1 and 4.6 GeV in the center of mass, and succeeds to the SuperB project from which it inherits most of the solutions proposed in this document. The work comes from a cooperation involving the INFN Frascati National Laboratories accelerator experts, the young newcomers, mostly engineers, of the Cabibbo Lab consortium and key collaborators from external laboratories.

physics.acc-ph↗

The Air Microwave Yield (AMY) experiment - A laboratory measurement of the microwave emission from extensive air showers

The AMY experiment aims to measure the microwave bremsstrahlung radiation (MBR) emitted by air-showers secondary electrons accelerating in collisions with neutral molecules of the atmosphere. The measurements are performed using a beam of 510 MeV electrons at the Beam Test Facility (BTF) of Frascati INFN National Laboratories. The goal of the AMY experiment is to measure in laboratory conditions the yield and the spectrum of the GHz emission in the frequency range between 1 and 20 GHz. The final purpose is to characterise the process to be used in a next generation detectors of ultra-high energy cosmic rays. A description of the experimental setup and the first results are presented.

astro-ph.IM↗