Search results for "NEUTRINOS"

Shell-model computed cross sections for charged-current scattering of astrophysical neutrinos off 40Ar

2018

Charged-current (anti)neutrino-$^{40}\mathrm{Ar}$ cross sections for astrophysical neutrinos have been calculated. The initial and final nuclear states were calculated using the nuclear shell model. The folded solar-neutrino scattering cross section was found to be $1.78(23)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}42}\phantom{\rule{4pt}{0ex}}{\mathrm{cm}}^{2}$, which is higher than what the previous papers have reported. The contributions from the ${1}^{\ensuremath{-}}$ and ${2}^{\ensuremath{-}}$ multipoles were found to be significant at supernova-neutrino energies, confirming the random-phase approximation (RPA) result of a previous study. The effects of neutrino flavor conve…

Supernova-neutrino induced reactions on molybdenum via neutral-currents

2012

In this thesis which consists of an introductory part and six publications the neutralcurrent neutrino-nucleus scatterings o the stable molybdenum nuclei are studied using microscopic nuclear models. The main focus is on supernova neutrinos and the nuclear responses to them for the aforementioned nuclei are computed by folding the computed cross sections with realistic neutrino-energy spectra. In this work both the coherent and incoherent contributions to the cross sections are considered. The contributions from the prominent multipole channels to the incoherent cross sections are also discussed in great detail.

A "DUAL" MODEL OF A MASSIVE SPIN-1/2 POINT PARTICLE, AND A THEORETICAL EXPLANATION FOR THE EFFECT OF "MAXIMAL PARITY-VIOLATION"

2006

The open question left by elementary particle physics about the origin of the so-called ``maximal parity-violation'' is dealt with. It is shown that an actual theoretical answer could be found within a new relativistic quantum field formalism being a strictly covariant fermion--antifermion extension of the usual one for massive fermions. This formalism can account naturally for the effect at issue, in such a way as even to restore both parity and charge-conjugation symmetries: it spontaneously provides a true ``chiral field'' approach, which gives rise to the conjecture of a pseudoscalar (extra) charge variety anticommuting with the scalar (ordinary) one and just underlying the ``maximally …

Extending Physics Potential of Large Liquid Scintillator Neutrino Detectors

2016

Evidence of Single State Dominance in the Two-Neutrino Double-β Decay of ^{82}Se with CUPID-0.

2019

We report on the measurement of the two-neutrino double-β decay of ^{82}Se performed for the first time with cryogenic calorimeters, in the framework of the CUPID-0 experiment. With an exposure of 9.95 kg yr of Zn^{82}Se, we determine the two-neutrino double-β decay half-life of ^{82}Se with an unprecedented precision level, T_{1/2}^{2ν}=[8.60±0.03(stat) _{-0.13}^{+0.19}(syst)]×10^{19}  yr. The very high signal-to-background ratio, along with the detailed reconstruction of the background sources allowed us to identify the single state dominance as the underlying mechanism of such a process, demonstrating that the higher state dominance hypothesis is disfavored at the level of 5.5σ.

Ultra-High Energy Neutrinos at the Pierre Auger Observatory

2013

The observation of ultrahigh energy neutrinos (UHE nu s) has become a priority in experimental astroparticle physics. UHE nu s can be detected with a variety of techniques. In particular, neutrinos can interact in the atmosphere (downward-going nu) or in the Earth crust (Earth-skimming nu), producing air showers that can be observed with arrays of detectors at the ground. With the surface detector array of the Pierre Auger Observatory we can detect these types of cascades. The distinguishing signature for neutrino events is the presence of very inclined showers produced close to the ground (i.e., after having traversed a large amount of atmosphere). In this work we review the procedure and …