相关论文: Oscillations of very low energy atmospheric neutri…
We consider oscillations of the low energy (sub-GeV sample) atmospheric neutrinos in the three neutrino context. We present the semi-analytic study of the neutrino evolution and calculate characteristics of the e-like events (total number,…
The minimal interpretation of the atmospheric neutrino data suggests that the muon neutrino oscillates into another species with a mixing angle close to the maximal $\pi/4$. In the Exact Parity Symmetric Model, both the muon and electron…
Use of low energy atmospheric neutrinos is considered for precision measurement of neutrino mixing parameters. At around energy $E \simeq$ a few $\times$100 MeV and baseline $L$ of a few $\times$1000 km, CP phase effect is $\sim$10 times…
We present the measurement of the the flux and angular distribution of atmospheric muon neutrinos using the MACRO detector. Three different event topologies are detected in two different energy ranges. High energy neutrinos (E~80 GeV) via…
New observations with atmospheric neutrinos from the underground experiments SuperKamiokande, Soudan 2, and MACRO, together with earlier results from Kamiokande and IMB, are reviewed. The most recent observations reconfirm aspects of…
Recent studies of atmospheric neutrinos and the results from CHOOZ and Palo-Verde experiment call for new and more sensitive searches for neutrino oscillations at reactors. The main goal of the project considered here is to look for very…
Upward throughgoing muons in underground detectors are induced by atmospheric $\nu_\mu$ with energies in the $1-10^4 GeV$ range. The oscillations of atmospheric muon neutrinos should affect mainly those with energy smaller than $E_\nu \sim…
The simplest explanation for the atmospheric neutrino anomaly is the transition of muon neutrinos and antineutrinos into states of different flavor. Data from the reactor experiment Chooz, and the measurement of the energy and angle…
Observations of atmospheric neutrinos by the SuperKamiokande collaboration have demonstrated large mixing of the muon-neutrino. However the present atmospheric neutrino data does not significantly constrain the associated mixing of the…
Neutrino oscillations with parameters relevant for the large mixing solution of the solar neutrino problem ($\Delta m^2_{21} = (2 - 20) \cdot 10^{-5}$ eV$^2$, $\sin^2 2\theta_{12} > 0.65$) can lead to observable (up to 10 - 12 %) excess of…
MACRO can detect three topologies of neutrino induced events, corresponding to different parent neutrino energies. The most numerous sample is made of upward throughgoing muons induced by atmospheric neutrinos of average energy 100 GeV. We…
We present the measurement of two event samples induced by atmospheric $\nu_\mu$ of average energy $ \bar {E}_\nu \sim 4 GeV$. In the first sample, the neutrino interacts inside the MACRO detector producing an upward-going muon leaving the…
After a short overview of the MACRO detector, located at the Gran Sasso Laboratory, I shall present and discuss the results on atmospheric muon neutrino oscillations, concerning low (<E_nu> ~ 4 GeV) and high (<E_nu> ~ 50 GeV) energy data.…
The flux of low energy atmospheric neutrinos (E_nu ~ 4 GeV) has been studied with the MACRO detector at Gran Sasso by detecting nu_mu interactions inside the apparatus, and by upward-going stopping muons. The updated analysis of the data…
A preliminary analysis is presented of low-energy ($\bar{E_\nu} \sim 4 GeV$) neutrino interactions observed by the MACRO detector. These include neutrino interactions in the detector, as well as upgoing neutrino-induced muons that stop in…
The Surface Detector of the Pierre Auger Observatory is sensitive to neutrinos of all flavours above 0.1 EeV. These interact through charged and neutral currents in the atmosphere giving rise to extensive air showers. When interacting…
We evaluate the upward shower and muon event rates for two characteristic four neutrino mixing models for extragalactic neutrinos, as well as for the atmospheric neutrinos, with energy thresholds of 1 TeV, 10 TeV and 100 TeV. We show that…
The flux of muons induced by atmospheric neutrinos has been measured with the MACRO detector. Different event topologies have been detected, due to neutrino interactions in the apparatus and in the rock below it. The upward-throughgoing…
We consider the oscillations of atmospheric neutrinos in the earth in the three-neutrino scheme with a $\Delta m^2$ hierarchy and a small admixture of the electron neutrino in the heavy mass eigenstate characterized by the mixing angle…
In the present work we propose to study neutrino oscillations employing sources of monoenergetic neutrinos following electron capture by the nucleus. Since the neutrino energy is very low the smaller of the two oscillation lengths, L23,…