scholarly journals IceCube Sterile Neutrino Searches

2019 ◽  
Vol 207 ◽  
pp. 04005 ◽  
Author(s):  
B. J. P. Jones
Keyword(s):  
Large Volume ◽  
Sterile Neutrino ◽  
Large Mass ◽  
Neutrino Telescope ◽  
Muon Neutrino ◽  
Sterile Neutrinos ◽  
Short Baseline ◽  
Mixing Angles ◽  
Neutrino Telescopes ◽  
Ongoing Work

Anomalies in short baseline experiments have been interpreted as evidence for additional neutrino mass states with large mass splittings from the known, active flavors. This explanation mandates a corresponding signature in the muon neutrino disappearance channel, which has yet to be observed. Searches for muon neutrino disappearance at the IceCube neutrino telescope presently provide the strongest limits in the space of mixing angles for eVscale sterile neutrinos. This proceeding for the Very Large Volume Neutrino Telescopes (VLVnT) Workshop summarizes the IceCube analyses that have searched for sterile neutrinos and describes ongoing work toward enhanced, high-statistics sterile neutrino searches.

scholarly journals Neutrino oscillations in the presence of super-light sterile neutrinos

2016 ◽  
Vol 31 (20n21) ◽  
pp. 1650123 ◽  
Author(s):  
Paraskevi Divari ◽  
John Vergados
Keyword(s):  
Sterile Neutrino ◽  
Neutral Current ◽  
Neutron Number ◽  
Electron Neutrino ◽  
Number Density ◽  
Sterile Neutrinos ◽  
Short Baseline ◽  
The Earth ◽  
Reactor Neutrino ◽  
Neutrino Experiments

In this paper, we study the effect of conversion of super-light sterile neutrino (SLSN) to electron neutrino in matter like that of the Earth. In the Sun the resonance conversion between SLSN and electron neutrino via the neutral current is suppressed due to the smallness of neutron number. On the other hand, neutron number density can play an important role in the Earth, making the scenario of SLSN quite interesting. The effect of CP-violating phases on active-SLSN oscillations is also discussed. Reactor neutrino experiments with medium or short baseline may probe the scenario of SLSN.

scholarly journals Exploring the new physics phases in 3+1 scenario in neutrino oscillation experiments

2021 ◽  
Vol 2021 (9) ◽  
Author(s):  
Nishat Fiza ◽  
Mehedi Masud ◽  
Manimala Mitra
Keyword(s):  
Neutrino Oscillation ◽  
Sterile Neutrino ◽  
New Physics ◽  
Double Beta Decay ◽  
Relevant Parameter ◽  
Neutrino Experiment ◽  
Short Baseline ◽  
Mixing Angles ◽  
Long Baseline ◽  
Deep Underground

Abstract The various global analyses of available neutrino oscillation data indicate the presence of the standard 3 + 0 neutrino oscillation picture. However, there are a few short baseline anomalies that point to the possible existence of a fourth neutrino (with mass in the eV-scale), essentially sterile in nature. Should sterile neutrino exist in nature and its presence is not taken into consideration properly in the analyses of neutrino data, the interference terms arising due to the additional CP phases in presence of a sterile neutrino can severely impact the physics searches in long baseline (LBL) neutrino oscillation experiments. In the current work we consider one light (eV-scale) sterile neutrino and probe all the three CP phases (δ13, δ24, δ34) in the context of the upcoming Deep Underground Neutrino Experiment (DUNE) and also estimate how the results improve when data from NOvA, T2K and T2HK are added in the analysis. We illustrate the ∆χ2 correlations of the CP phases among each other, and also with the three active-sterile mixing angles. Finally, we briefly illustrate how the relevant parameter spaces in the context of neutrinoless double beta decay get modified in light of the bounds in presence of a light sterile neutrino.

scholarly journals Search for signatures of sterile neutrinos with Double Chooz

2021 ◽  
Vol 81 (8) ◽  
Author(s):  
T. Abrahão ◽  
H. Almazan ◽  
J. C. dos Anjos ◽  
S. Appel ◽  
J. C. Barriere ◽  
...  
Keyword(s):  
Model Prediction ◽  
Sterile Neutrino ◽  
Profile Likelihood ◽  
Mass Range ◽  
Neutrino Mixing ◽  
Sterile Neutrinos ◽  
Mixing Angles ◽  
Data Comparison ◽  
Mixing Parameter ◽  
Double Chooz

AbstractWe present a search for signatures of neutrino mixing of electron anti-neutrinos with additional hypothetical sterile neutrino flavors using the Double Chooz experiment. The search is based on data from 5 years of operation of Double Chooz, including 2 years in the two-detector configuration. The analysis is based on a profile likelihood, i.e. comparing the data to the model prediction of disappearance in a data-to-data comparison of the two respective detectors. The analysis is optimized for a model of three active and one sterile neutrino. It is sensitive in the typical mass range $${5 \times 10^{-3}}\,\mathrm{eV}^2 \lesssim \varDelta m^2_{41} \lesssim {3 \times 10^{-1}}\,\mathrm{eV}^2 $$ 5 × 10 - 3 eV 2 ≲ Δ m 41 2 ≲ 3 × 10 - 1 eV 2 for mixing angles down to $$\sin ^2 2\theta _{14} \gtrsim {0.02} $$ sin 2 2 θ 14 ≳ 0.02 . No significant disappearance additionally to the conventional disappearance related to $$\theta _{13} $$ θ 13 is observed and correspondingly exclusion bounds on the sterile mixing parameter $$\theta _{14} $$ θ 14 as a function of $$ \varDelta m^2_{41} $$ Δ m 41 2 are obtained.

scholarly journals keV sterile neutrino with large mixing angle is still alive

2018 ◽  
Vol 191 ◽  
pp. 08003
Author(s):  
Anton Chudaykin
Keyword(s):  
Sterile Neutrino ◽  
Sterile Neutrinos ◽  
Mixing Angle ◽  
Mixing Angles ◽  
Hidden Sector ◽  
The Standard Model ◽  
Neutrino Experiments ◽  
Active Mixing ◽  
Neutrino Decay ◽  
Made In

We study production of keV scale sterile neutrinos with large mixing with the Standard Model sector [1]. Conventional mechanism of sterile neutrino generation in the early Universe leads to overproduction of the Dark Matter and strong X-ray signal from sterile neutrino decay. It makes anticipated groundbased experiments on direct searches of sterile-active mixing unfeasible. We argue that for models with a hidden sector coupled to the sterile neutrinos cosmological and astrophysical constraints can be significantly alleviated. In developed scenario a phase transition in the hidden sector modifies the standard oscillation picture and leads to significantly larger mixing angles, thus opening new perspectives for future neutrino experiments such as Troitsk v-mass and KATRIN. This work was made in collaboration with Fedor Bezrukov and Dmitry Gorbunov.

scholarly journals Roles of sterile neutrinos in particle physics and cosmology

2019 ◽  
Vol 34 (10) ◽  
pp. 1930005 ◽  
Author(s):  
Sin Kyu Kang
Keyword(s):  
Dark Matter ◽  
Particle Physics ◽  
Sterile Neutrino ◽  
Electron Neutrino ◽  
Type I ◽  
Sterile Neutrinos ◽  
Short Baseline ◽  
Cosmological Observations ◽  
Cosmological Data ◽  
Electron Neutrino Appearance

The impacts of the light sterile neutrino hypothesis in particle physics and cosmology are reviewed. The observed short baseline neutrino anomalies challenging the standard explanation of neutrino oscillations within the framework of three active neutrinos are addressed. It is shown that they can be interpreted as the experimental hints pointing towards the existence of sterile neutrino at the eV scale. While the electron neutrino appearance and disappearance data are in favor of such a sterile neutrino, the muon disappearance data disfavor it, which gives rise to a strong appearance–disappearance tension. After a brief review on the cosmological effects of light sterile neutrinos, proposed signatures of light sterile neutrinos in the existing cosmological data are discussed. The keV-scale sterile neutrinos as possible dark matter candidates are also discussed by reviewing different mechanisms of how they can be produced in the early Universe and how their properties can be constrained by several cosmological observations. We give an overview of the possibility that keV-scale sterile neutrino can be a good DM candidate and play a key role in achieving low-scale leptogenesis simultaneously by introducing a model where an extra light sterile neutrino is added on top of type I seesaw model.

scholarly journals Supernova bounds on keV-mass sterile neutrinos

2015 ◽  
Vol 30 (13) ◽  
pp. 1530033 ◽  
Author(s):  
Shun Zhou
Keyword(s):  
Dark Matter ◽  
Energy Loss ◽  
Cold Dark Matter ◽  
Sterile Neutrino ◽  
Small Scale ◽  
Neutrino Masses ◽  
Neutrino Mixing ◽  
Sterile Neutrinos ◽  
Mixing Angles ◽  
Standard Energy

Sterile neutrinos of keV masses are one of the most promising candidates for the warm dark matter, which could solve the small-scale problems encountered in the scenario of cold dark matter. We present a detailed study of the production of such sterile neutrinos in a supernova core, and derive stringent bounds on the active-sterile neutrino mixing angles and sterile neutrino masses based on the standard energy-loss argument.

scholarly journals Sterile Neutrinos with Neutrino Telescopes

Universe ◽  
2021 ◽  
Vol 7 (11) ◽  
pp. 426
Author(s):  
Carlos A. Argüelles ◽  
Jordi Salvado
Keyword(s):  
Liquid Scintillator ◽  
Atmospheric Neutrino ◽  
Neutrino Flux ◽  
Electron Neutrino ◽  
Anthropogenic Sources ◽  
Current Status ◽  
Neutrino Experiment ◽  
Sterile Neutrinos ◽  
Short Baseline ◽  
Neutrino Telescopes

Searches for light sterile neutrinos are motivated by the unexpected observation of an electron neutrino appearance in short-baseline experiments, such as the Liquid Scintillator Neutrino Detector (LSND) and the Mini Booster Neutrino Experiment (MiniBooNE). In light of these unexpected results, a campaign using natural and anthropogenic sources to find the light (mass-squared-difference around 1 eV2) sterile neutrinos is underway. Among the natural sources, atmospheric neutrinos provide a unique gateway to search for sterile neutrinos due to the broad range of baseline-to-energy ratios, L/E, and the presence of significant matter effects. Since the atmospheric neutrino flux rapidly falls with energy, studying its highest energy component requires gigaton-scale neutrino detectors. These detectors—often known as neutrino telescopes since they are designed to observe tiny astrophysical neutrino fluxes—have been used to perform searches for light sterile neutrinos, and researchers have found no significant signal to date. This brief review summarizes the current status of searches for light sterile neutrinos with neutrino telescopes deployed in solid and liquid water.

scholarly journals Sterile Neutrino Fits to Short-Baseline Neutrino Oscillation Measurements

2013 ◽  
Vol 2013 ◽  
pp. 1-26 ◽  
Author(s):  
J. M. Conrad ◽  
C. M. Ignarra ◽  
G. Karagiorgi ◽  
M. H. Shaevitz ◽  
J. Spitz
Keyword(s):  
Neutrino Oscillation ◽  
Neutrino Mass ◽  
Goodness Of Fit ◽  
Sterile Neutrino ◽  
Low Energy ◽  
Data Sets ◽  
Sterile Neutrinos ◽  
Short Baseline ◽  
Energy Excess ◽  
Global Fit

This paper reviews short-baseline oscillation experiments as interpreted within the context of one, two, and three sterile neutrino models associated with additional neutrino mass states in the~1 eV range. Appearance and disappearance signals and limits are considered. We show that fitting short-baseline datasets to a 3 + 3 (3 + 2) model, defined by three active and three (two) sterile neutrinos, results in an overall goodness of fit of 67% (69%) and good compatibility between data sets—to be compared to a 3 + 1 model with a 55% goodness of fit. While the (3 + 3) fit yields the highest quality overall, it still finds inconsistencies with the MiniBooNE appearance datasets; in particular, the global fit fails to account for the observed MiniBooNE low-energy excess. Given the overall improvement, we recommend using the results of (3 + 2) and (3 + 3) fits, rather than (3 + 1) fits, for future neutrino oscillation phenomenology. These results motivate the pursuit of further short-baseline experiments, such as those reviewed in this paper.

Implications of Higgs’ universality for physics beyond the Standard Model

2017 ◽  
Vol 32 (16) ◽  
pp. 1742003
Author(s):  
T. Goldman ◽  
G. J. Stephenson
Keyword(s):  
Standard Model ◽  
Sterile Neutrino ◽  
Current Data ◽  
Fermion Mass ◽  
Beyond The Standard Model ◽  
Sterile Neutrinos ◽  
Short Baseline ◽  
Seesaw Mechanism ◽  
The Standard Model ◽  
Mass Terms

We emulate Cabibbo by assuming a kind of universality for fermion mass terms in the Standard Model. We show that this is consistent with all current data and with the concept that deviations from what we term Higgs’ universality are due to corrections from currently unknown physics of nonetheless conventional form. The application to quarks is straightforward, while the application to leptons makes use of the recognition that Dark Matter can provide the “sterile” neutrinos needed for the seesaw mechanism. Requiring agreement with neutrino oscillation results leads to the prediction that the mass eigenstates of the sterile neutrinos are separated by quadratically larger ratios than for the charged fermions. Using consistency with the global fit to LSND-like, short-baseline oscillations to determine the scale of the lowest mass sterile neutrino strongly suggests that the recently observed astrophysical 3.55 keV [Formula: see text]-ray line is also consistent with the mass expected for the second most massive sterile neutrino in our analysis.

scholarly journals Numerical estimate of minimal active-sterile neutrino mixing

2018 ◽  
Vol 191 ◽  
pp. 03003
Author(s):  
Igor Krasnov
Keyword(s):  
Neutrino Mass ◽  
Sterile Neutrino ◽  
Numerical Estimate ◽  
Strong Dependence ◽  
Type I ◽  
Mass Hierarchy ◽  
Neutrino Mixing ◽  
Sterile Neutrinos ◽  
Mixing Angles ◽  
Active Neutrino

Seesaw mechanism constrains from below mixing between active and sterile neutrinos for fixed sterile neutrino masses. Signal events associated with sterile neutrino decays inside a detector at fixed target experiment are suppressed by the mixing angle to the power of four. Therefore sensitivity of experiments such as SHiP and DUNE should take into account minimal possible values of the mixing angles. We extend the previous study of this subject [1] to a more general case of non-zero CP-violating phases in the neutrino sector. Namely, we provide numerical estimate of minimal value of mixing angles between active neutrinos and two sterile neutrinos with the third sterile neutrino playing no noticeable role in the mixing. Thus we obtain a sensitivity needed to fully explore the seesaw type I mechanism for sterile neutrinos with masses below 2 GeV, and one undetectable sterile neutrino that is relevant for the fixedtarget experiments. Remarkably, we observe a strong dependence of this result on the lightest active neutrino mass and the neutrino mass hierarchy, not only on the values of CP-violating phases themselves. All these effects sum up to push the limit of experimental confirmation of sterile-active neutrino mixing by several orders of magnitude below the results of [1] from 10-10 - 10-11 down to 10-12 and even to 10-20 in parts of parameter space; non-zero CP-violating phases are responsible for that.

Sign in / Sign up

Export Citation Format

Share Document