P. Lombardi
A5081823091- Neutrino Physics Research
- Astrophysics and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- Atmospheric Ozone and Climate
- Solar and Space Plasma Dynamics
- Satellite Communication Systems
- Historical and Environmental Studies
- Radioactive Decay and Measurement Techniques
- Italian Fascism and Post-war Society
- Astro and Planetary Science
- Nuclear Physics and Applications
- Italian Social Issues and Migration
- Educational and Social Studies
- Radioactive contamination and transfer
- Cosmology and Gravitation Theories
- Scientific Research and Discoveries
- Nuclear physics research studies
- Legal and Labor Studies
- Spacecraft Design and Technology
- CCD and CMOS Imaging Sensors
- Quantum, superfluid, helium dynamics
Istituto Nazionale di Fisica Nucleare, Sezione di Milano
2015-2025
University of Milan
2003-2024
Universidade Estadual de Londrina
2022-2024
Université Libre de Bruxelles
2022-2024
China Institute of Atomic Energy
2024
China Academy of Space Technology
2024
Pontifical Catholic University of Rio de Janeiro
2022-2024
A. Alikhanyan National Laboratory
2022-2024
Beijing Normal University
2022-2024
Politecnico di Milano
2013-2023
This white paper addresses the hypothesis of light sterile neutrinos based on recent anomalies observed in neutrino experiments and latest astrophysical data.
We report the direct measurement of 7Be solar neutrino signal rate performed with Borexino detector at Laboratori Nazionali del Gran Sasso. The interaction 0.862 MeV neutrinos is 49+/-3stat+/-4syst counts/(day.100 ton). hypothesis no oscillation for inconsistent our 4sigma C.L. Our result first survival probability nu(e) in transition region between matter-enhanced and vacuum-driven oscillations. improves experimental determination flux 7Be, pp, CNO nu(e), limit on effective magnetic moment...
Borexino has been running since May 2007 at the LNGS with primary goal of detecting solar neutrinos. The detector, a large, unsegmented liquid scintillator calorimeter characterized by unprecedented low levels intrinsic radioactivity, is optimized for study lower energy part spectrum. During Phase-I (2007-2010) first detected and then precisely measured flux 7Be neutrinos, ruled out any significant day-night asymmetry their interaction rate, made direct observation pep set tightest upper...
We observed, for the first time, solar neutrinos in 1.0-1.5 MeV energy range. measured rate of pep neutrino interactions Borexino to be [3.1+-0.6(stat)+-0.3(syst)] counts/(day x 100 ton) and provided a constraint on CNO interaction <7.9 (95% C.L.). The absence signal is disfavored at 99.97% C.L., while 98% C.L. This unprecedented sensitivity was achieved by adopting novel data analysis techniques rejection cosmogenic 11C, dominant background 1-2 region. Assuming MSW-LMA solution...
We report the first results of DarkSide-50, a direct search for dark matter operating in underground Laboratori Nazionali del Gran Sasso (LNGS) and searching rare nuclear recoils possibly induced by weakly interacting massive particles (WIMPs). The detector is Liquid Argon Time Projection Chamber with (46.4+-0.7) kg active mass, operated inside 30 t organic liquid scintillator neutron veto, which turn installed at center 1 kt water Cherenkov veto residual flux cosmic rays. here null...
Geo-neutrinos, electron anti-neutrinos produced in beta decays of naturally occurring radioactive isotopes the Earth, are a unique direct probe our planet's interior. We report first observation at more than 3$\sigma$ C.L. geo-neutrinos, performed with Borexino detector Laboratori Nazionali del Gran Sasso. Anti-neutrinos detected through neutron inverse decay reaction. With 252.6 ton-yr fiducial exposure after all selection cuts, we 9.9^{+4.1}_{-3.4}(^{+14.6}_{-8.2}) geo-neutrino events,...
Liquid argon is a bright scintillator with potent particle identification properties, making it an attractive target for direct-detection dark matter searches. The DarkSide-50 search here reports the first WIMP results obtained using of low-radioactivity argon. detector, two-phase liquid time projection chamber, located at Laboratori Nazionali del Gran Sasso. underground shown to contain Ar-39 level reduced by factor (1.4 +- 0.2) x 10^3 relative atmospheric We report background-free null...
A bstract The very low radioactive background of the Borexino detector, its large size, and well proved capability to detect both energy electron neutrinos antineutrinos make an ideal case for study short distance neutrino oscillations with artificial sources at Gran Sasso. This paper describes possible layouts 51 Cr ( ν e ) 144 Ce- Pr $$ \left( {{{\overline{\nu}}_e}} \right) source experiments in shows expected sensitivity eV mass sterile three different phases experiment. Expected results...
We present a measurement of the geo--neutrino signal obtained from 1353 days data with Borexino detector at Laboratori Nazionali del Gran Sasso in Italy. With fiducial exposure (3.69 $\pm$ 0.16) $\times$ $10^{31}$ proton year after all selection cuts and background subtraction, we detected (14.3 4.4) geo-neutrino events assuming fixed chondritic mass Th/U ratio 3.9. This corresponds to $S_{geo}$ = (38.8 12.0) TNU just 6 $10^{-6}$ probability for null measurement. U Th left as free parameters...
We report an improved geo-neutrino measurement with Borexino from 2056 days of data taking. The present exposure is $(5.5\pm0.3)\times10^{31}$ proton$\times$yr. Assuming a chondritic Th/U mass ratio 3.9, we obtain $23.7 ^{+6.5}_{-5.7} (stat) ^{+0.9}_{-0.6} (sys)$ events. null observation geo-neutrinos alone has probability $3.6 \times 10^{-9}$ (5.9$\sigma$). A signal the mantle obtained at 98\% C.L. radiogenic heat production for U and Th best-fit result restricted to range 23-36 TW, taking...
Borexino, a liquid scintillator detector at LNGS, is designed for the detection of neutrinos and antineutrinos from Sun, supernovae, nuclear reactors, Earth. The feeble nature these signals requires strong suppression backgrounds below few MeV. Very low intrinsic radiogenic contamination all components needs to be accompanied by efficient identification muons muon-induced backgrounds. Muons produce unstable nuclei spallation processes along their trajectory through whose decays can mimic...
We have measured the muon flux at underground Gran Sasso National Laboratory (3800 m w.e.) to be (3.41 \pm 0.01) \times 10-4m-2s-1 using four years of Borexino data. A modulation this signal is observed with a period (366\pm3) days and relative amplitude (1.29 0.07)%. The phase (179 6) days, corresponding maximum on 28th June. Using most complete atmospheric data models available, rate fluctuations are shown positively correlated temperature, an effective coefficient {\alpha}T = 0.93 0.04....
A search for 5.5-MeV solar axions produced in the $p+d\rightarrow\rm{^3He}+A (5.5 \rm{MeV})$ reaction was performed using Borexino detector. The Compton conversion of to photons, ${\rm A}+e\rightarrow e+\gamma$; axio-electric effect, A}+e+Z\rightarrow e+Z$; decay into two A}\rightarrow2\gamma$; and inverse Primakoff on nuclei, A}+Z\rightarrow\gamma+Z$, are considered. Model independent limits axion-electron ($g_{Ae}$), axion-photon ($g_{A\gamma}$), isovector axion-nucleon ($g_{3AN}$)...
We report the first measurement of CNO solar neutrinos by Borexino that uses Correlated Integrated Directionality (CID) method, exploiting sub-dominant Cherenkov light in liquid scintillator detector. The directional information origin is preserved fast photons from neutrino scattered electrons, and used to discriminate between signal background. independent spectral on which previous measurements were based. While analysis could only be applied Phase-III dataset, can use complete data...
The solar neutrino experiment Borexino, which is located in the Gran Sasso underground laboratories, a unique position to study muon-induced backgrounds an organic liquid scintillator. In this study, large sample of cosmic muons identified and tracked by muon veto detector external scintillator, specific light patterns observed when cross scintillator volume. yield neutrons found be Yn = (3.10±0.11)·10−4 n/(μ·(g/cm2)). distance profile between parent track neutron capture point has average...