Viability of $Δm^2\sim$ 1 eV$^2$ sterile neutrino mixing models in light of MiniBooNE electron neutrino and antineutrino data from the Booster and NuMI beamlines

Sterile neutrinos with neutrino telescopes

Searches for light sterile neutrinos are motivated by the unexpected observation of 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 light -- mass-squared-difference around 1 eV$^{2}$ -- 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…

Discovering New Light States at Neutrino Experiments

Experiments designed to measure neutrino oscillations also provide major opportunities for discovering very weakly coupled states. In order to produce neutrinos, experiments such as LSND collide thousands of Coulombs of protons into fixed targets, while MINOS and MiniBooNE also focus and then dump beams of muons. The neutrino detectors beyond these beam dumps are therefore an excellent arena in which to look for long-lived pseudoscalars or for vector bosons that kinetically mix with the photon. We show that these experiments have significant sensitivity beyond previous beam dumps, and are able…

Light sterile neutrinos and their implications on currently running long-baseline and neutrinoless double beta decay experiments

Recent $ν_e$ appearance data from the Mini Booster Neutrino Experiment (MiniBooNE) are in support of the excess of events reported by the Liquid Scintillator Neutrino Detector (LSND), which provides an indirect hint for the existence of eV-scale sterile neutrino. As these sterile neutrinos can mix with the standard active neutrinos, in this paper we explore the effect of such active-sterile mixing on the determination of various oscillation parameters by the currently running long-baseline neutrino experiments T2K and NO$ν$A. We find that the existence of sterile neutrino can lead to new kind …

短基线实验中的衰变惰性中微子

Decaying sterile neutrinos at short baselines

本文利用 MicroBooNE 新数据重新检验衰变惰性中微子对 MiniBooNE 和 LSND 短基线反常的解释，并在两种衰变模型参数空间中给出新限制，发现该解释在大部分参数空间被以超过 99% 置信水平排除。

Combining $ν_e$ Appearance and $ν_μ$ Disappearance Channels in Light Sterile Neutrino Oscillation Searches at Fermilab's Short-Baseline Neutrino Facility

Of late, a number of instances of neutrino flux anomalies observed at short-baselines have given traction to the hypothesis of adding new neutrino flavours to our Standard Model set, albeit ones not associated with a partnered lepton. Anomalies observed at LSND, MiniBooNE and at short distances from nuclear reactors have suggested the existence of sterile mass states with masses on the scale of $\sim1\text{eV}$, prompting further investigations. Subsequently, Fermilab is set to host a Short-Baseline Neutrino (SBN) oscillation program which will cross-check each of these anomalies by deploying …

Accelerator-based Short-baseline Neutrino Oscillation Experiments

Over the last two decades, several experiments have reported anomalous results that could be hinting at the exciting possibility of sterile neutrino states in the $eV^{2}$ mass scale. Liquid Argon Time Projection Chambers (LArTPCs) are a particularly promising technology to explore this physics due to their fine-grained tracking and exceptional calorimetric capabilities. The MicroBooNE experiment, a 170 ton LArTPC scheduled to start taking data very soon with Fermilab's Booster Neutrino Beam (BNB), will combine LArTPC development with the main physics goal of understanding the low-energy elect…

在存在轻惰性中微子的情况下利用绝对质量相关观测量约束质量谱

Constraining the mass-spectra in the presence of a light sterile neutrino from absolute mass-related observables

本文研究轻惰性中微子不同质量谱对中微子绝对质量相关观测量（宇宙学质量之和、β衰变有效质量、无中微子双β衰变有效马约拉纳质量）的影响，并利用当前约束及KATRIN、Project-8、nEXO等未来灵敏度排除部分情景。

First Measurement of Monoenergetic Muon Neutrino Charged Current Interactions

We report the first measurement of monoenergetic muon neutrino charged current interactions. MiniBooNE has isolated 236 MeV muon neutrino events originating from charged kaon decay at rest ($K^+ \rightarrow μ^+ ν_μ$) at the NuMI beamline absorber. These signal $ν_μ$-carbon events are distinguished from primarily pion decay in flight $ν_μ$ and $\overlineν_μ$ backgrounds produced at the target station and decay pipe using their arrival time and reconstructed muon energy. The significance of the signal observation is at the 3.9$σ$ level. The muon kinetic energy, neutrino-nucleus energy transfer (…