arXiv subjects

Orlando Luis Goulart Peres

Publications and source records attributed to Orlando Luis Goulart Peres.

3 recordsLinked to original sources

arXiv2021

Testing non-standard neutrino interactions in (anti)-electron neutrino disappearance experiments

We search for scalar and tensor non-standard interactions using (anti)-electron neutrino disappearance in oscillation data. We found a slight preference for non-zero CP violation, coming from both tensor and scalar interactions. The preference for CP violation is lead by Daya Bay low-energy data with a significance that reaches $\sim1.7σ$ in the global analysis (and $\sim2.1σ$ when considering only medium baseline reactors data) compared to the standard neutrino oscillation scenario.

hep-ph↗

arXiv2020

Improvements on perturbative oscillation formulas including non-standard neutrino Interactions

We present perturbative oscillation probabilities for electron and muon channels including non-standard interaction (NSI) effects. The perturbation was performed in standard parameters $Δm^2_{21}/Δm^2_{31}$ and $\sin^2{(θ_{13})}$ as in non-standard interaction couplings. Our goal is to match non-standard parameters with the standard ones. This leads to oscillation probabilities with NSI compact and with functional structure similar to the Standard Oscillation (SO) case. Such formalism allows us to recognize degeneracies between standard oscillation parameters and NSI parameters. In such scenario, we also have an educated guess about the origin of the reported behavior of long-baseline experiments degeneracies, which should be due to marginalization on standard oscillation parameters $δ_{\rm CP}$, $θ_{23}$ and NSI parameters.

hep-ph↗

arXiv2012

New limits on neutrino magnetic moment through non-vanishing 13-mixing

The relatively large value of neutrino mixing angle θ_{13} set by recent measurements allows us to use solar neutrinos to set a limit on neutrino magnetic moment involving second and third families, μ_{μτ}. The existence of a random magnetic field in solar convective zone can produce a significant anti-neutrino flux when a non-vanishing neutrino magnetic moment is assumed. Even if we consider a vanishing neutrino magnetic moment involving the first family, electron anti-neutrinos are indirectly produced through the mixing between first and third families and non-vanishing μ_{μτ}. Using KamLAND limits on the solar flux of electron anti-neutrino, we set the limit μ_{μτ} < 0.5e-11 Bohr magneton for a reasonable assumption on the behavior of solar magnetic fields. This is the first time a limit on μ_{μτ} is established in the literature directly from neutrino interaction with magnetic fields, and, interestingly enough, is comparable with the limits on neutrino magnetic moment involving the first family and with the ones coming from modifications on electroweak cross section.

hep-ph↗