We measure a large set of observables in inclusive charged current muon neutrino scattering on argon with the MicroBooNE liquid argon time projection chamber operating at Fermilab. We evaluate three ...neutrino interaction models based on the widely used GENIE event generator using these observables. The measurement uses a data set consisting of neutrino interactions with a final state muon candidate fully contained within the MicroBooNE detector. These data were collected in 2016 with the Fermilab Booster Neutrino Beam, which has an average neutrino energy of Formula omitted, using an exposure corresponding to Formula omitted protons-on-target. The analysis employs fully automatic event selection and charged particle track reconstruction and uses a data-driven technique to separate neutrino interactions from cosmic ray background events. We find that GENIE models consistently describe the shapes of a large number of kinematic distributions for fixed observed multiplicity.
We measure a large set of observables in inclusive charged current muon neutrino scattering on argon with the MicroBooNE liquid argon time projection chamber operating at Fermilab. We evaluate three ...neutrino interaction models based on the widely used GENIE event generator using these observables. The measurement uses a data set consisting of neutrino interactions with a final state muon candidate fully contained within the MicroBooNE detector. These data were collected in 2016 with the Fermilab Booster Neutrino Beam, which has an average neutrino energy of 800MeV, using an exposure corresponding to 5.0×1019 protons-on-target. The analysis employs fully automatic event selection and charged particle track reconstruction and uses a data-driven technique to separate neutrino interactions from cosmic ray background events. We find that GENIE models consistently describe the shapes of a large number of kinematic distributions for fixed observed multiplicity.
We present the first measurement of differential cross sections for charged-current muon neutrino interactions on argon with one muon, two protons, and no pions in the final state. Such interactions ...leave the target nucleus in a two-particle two-hole state; these states are of great interest, but currently there is limited information about their production in neutrino-nucleus interactions. Detailed investigations of the production of two-particle two-hole states are vital to support upcoming experiments exploring the nature of the neutrino, and the development of the liquid-argon time-projection-chamber has made possible the isolation of such final states. The opening angle between the two protons, the angle between the total proton momentum and the muon, and the total transverse momentum of the final state system are sensitive to the underlying physics processes as embodied in a variety of models. Realistic initial-state momentum distributions are shown to be important in reproducing the data.
Phys. Rev. Lett. 132, 151801 Published 10 April 2024 We present a measurement of $\eta$ production from neutrino interactions on
argon with the MicroBooNE detector. The modeling of resonant neutrino
...interactions on argon is a critical aspect of the neutrino oscillation physics
program being carried out by the DUNE and Short Baseline Neutrino programs.
$\eta$ production in neutrino interactions provides a powerful new probe of
resonant interactions, complementary to pion channels, and is particularly
suited to the study of higher-order resonances beyond the $\Delta(1232)$. We
measure a flux-integrated cross section for neutrino-induced $\eta$ production
on argon of $3.22 \pm 0.84 \; \textrm{(stat.)} \pm 0.86 \; \textrm{(syst.)}$
$10^{-41}{\textrm{cm}}^{2}$/nucleon. By demonstrating the successful
reconstruction of the two photons resulting from $\eta$ production, this
analysis enables a novel calibration technique for electromagnetic showers in
GeV accelerator neutrino experiments.
MicroBooNE is a neutrino experiment located in the Booster Neutrino Beamline
(BNB) at Fermilab, which collected data from 2015 to 2021. MicroBooNE's liquid
argon time projection chamber (LArTPC) is ...accompanied by a photon detection
system consisting of 32 photomultiplier tubes used to measure the argon
scintillation light and determine the timing of neutrino interactions. Analysis
techniques combining light signals and reconstructed tracks are applied to
achieve a neutrino interaction time resolution of $\mathcal{O}(1\,\text{ns})$.
The result obtained allows MicroBooNE to access the ns neutrino pulse structure
of the BNB for the first time. The timing resolution achieved will enable
significant enhancement of cosmic background rejection for all neutrino
analyses. Furthermore, the ns timing resolution opens new avenues to search for
long-lived-particles such as heavy neutral leptons in MicroBooNE, as well as in
future large LArTPC experiments, namely the SBN program and DUNE.
We present the first measurement of the cross section of Cabibbo-suppressed
$\Lambda$ baryon production, using data collected with the MicroBooNE detector
when exposed to the neutrinos from the Main ...Injector beam at the Fermi National
Accelerator Laboratory. The data analyzed correspond to $2.2 \times 10^{20}$
protons on target of neutrino mode running and $4.9 \times 10^{20}$ protons on
target of anti-neutrino mode running. An automated selection is combined with
hand scanning, with the former identifying five candidate $\Lambda$ production
events when the signal was unblinded, consistent with the GENIE prediction of
$5.3 \pm 1.1$ events. Several scanners were employed, selecting between three
and five events, compared with a prediction from a blinded Monte Carlo
simulation study of $3.7 \pm 1.0$ events. Restricting the phase space to only
include $\Lambda$ baryons that decay above MicroBooNE's detection thresholds,
we obtain a flux averaged cross section of $2.0^{+2.2}_{-1.7} \times 10^{-40}$
cm$^2/$Ar, where statistical and systematic uncertainties are combined.
We present a search for eV-scale sterile neutrino oscillations in the MicroBooNE liquid argon detector, simultaneously considering all possible appearance and disappearance effects within the \(3+1\) ...active-to-sterile neutrino oscillation framework. We analyze the neutrino candidate events for the recent measurements of charged-current \(\nu_e\) and \(\nu_{\mu}\) interactions in the MicroBooNE detector, using data corresponding to an exposure of 6.37\(\times\)10\(^{20}\) protons on target from the Fermilab booster neutrino beam. We observe no evidence of light sterile neutrino oscillations and derive exclusion contours at the \(95\%\) confidence level in the plane of the mass-squared splitting \(\Delta m^2_{41}\) and the sterile neutrino mixing angles \(\theta_{\mu e}\) and \(\theta_{ee}\), excluding part of the parameter space allowed by experimental anomalies. Cancellation of \(\nu_e\) appearance and \(\nu_e\) disappearance effects due to the full \(3+1\) treatment of the analysis leads to a degeneracy when determining the oscillation parameters, which is discussed in this paper and will be addressed by future analyses.
We present a search for long-lived Higgs portal scalars (HPS) and heavy neutral leptons (HNL) decaying in the MicroBooNE liquid-argon time projection chamber. The measurement is performed using data ...collected synchronously with the NuMI neutrino beam from Fermilab's Main Injector with a total exposure corresponding to \(7.01 \times 10^{20}\) protons on target. We set upper limits at the \(90\%\) confidence level on the mixing parameter \(\lvert U_{\mu 4}\rvert^2\) ranging from \(\lvert U_{\mu 4}\rvert^2<12.9\times 10^{-8}\) for Majorana HNLs with a mass of \(m_{\rm HNL}=246\) MeV to \(\lvert U_{\mu 4}\rvert^2<0.92 \times 10^{-8}\) for \(m_{\rm HNL}=385\) MeV, assuming \(\lvert U_{e 4}\rvert^2 = \lvert U_{\tau 4}\rvert^2 = 0\) and HNL decays into \(\mu^\pm\pi^\mp\) pairs. These limits on \(\lvert U_{\mu 4}\rvert^2\) represent an order of magnitude improvement in sensitivity compared to the previous MicroBooNE result. We also constrain the scalar-Higgs mixing angle \(\theta\) by searching for HPS decays into \(\mu^+\mu^-\) final states, excluding a contour in the parameter space with lower bounds of \(\theta^2<31.3 \times 10^{-9}\) for \(m_{\rm HPS}=212\) GeV and \(\theta^2<1.09 \times 10^{-9}\) for \(m_{\rm HPS}=275\) GeV. These are the first constraints on the scalar-Higgs mixing angle \(\theta\) from a dedicated experimental search in this mass range.
The MicroBooNE liquid argon time projection chamber (LArTPC) maintains a high level of liquid argon purity through the use of a filtration system that removes electronegative contaminants in ...continuously-circulated liquid, recondensed boil off, and externally supplied argon gas. We use the MicroBooNE LArTPC to reconstruct MeV-scale radiological decays. Using this technique we measure the liquid argon filtration system's efficacy at removing radon. This is studied by placing a 500 kBq \(^{222}\)Rn source upstream of the filters and searching for a time-dependent increase in the number of radiological decays in the LArTPC. In the context of two models for radon mitigation via a liquid argon filtration system, a slowing mechanism and a trapping mechanism, MicroBooNE data supports a radon reduction factor of greater than 99.999% or 97%, respectively. Furthermore, a radiological survey of the filters found that the copper-based filter material was the primary medium that removed the \(^{222}\)Rn. This is the first observation of radon mitigation in liquid argon with a large-scale copper-based filter and could offer a radon mitigation solution for future large LArTPCs.