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The flux of cosmic ray muons at the Earth’s surface exhibits seasonal variations due to changes in the temperature of the atmosphere affecting the production and decay of mesons in the upper atmosphere. Using 1473 live days of data collected by the NuMI Off-axis ${\nu }_e$Appearance (NOvA) Near Detector during 2018–2022, we studied the seasonal pattern in the multiple-muon event rate. The data confirm an anticorrelation between the multiple-muon event rate and effective atmospheric temperature, consistent across all the years of data. Previous analyses from MINOS and NOvA saw a similar anticorrelation but did not include an explanation. We find that this anticorrelation is driven by altitude–geometry effects as the average muon production height changes with the season. This has been studied with a CORSIKA cosmic ray simulation package by varying atmospheric parameters, and provides an explanation to a longstanding discrepancy between the seasonal phases of single and multiple-muon events. 

This Letter reports measurements of muon-neutrino disappearance and electron-neutrino appearance and the corresponding antineutrino processes between the two NOvA detectors in the NuMI neutrino beam. These measurements use a dataset with double the neutrino mode beam exposure that was previously analyzed, along with improved simulation and analysis techniques. A joint fit to these samples in the three-flavor paradigm results in the most precise single-experiment constraint on the atmospheric neutrino mass splitting, $\mathrm{\Delta }{m}_{32}^2=2.431_{-0.034}^{+0.036}(-2.479_{-0.036}^{+0.036})\times {10}^{-3}{\mathrm{eV}}^2$if the mass ordering is normal (inverted). In both orderings, a region close to maximal mixing with ${\sin }^2{\theta }_{23}=0.55_{-0.06}^{+0.02}$is preferred. The NOvA data show a mild preference for the normal mass ordering with a Bayes factor of 2.4 (corresponding to 70% of the posterior probability), indicating that the normal ordering is 2.4 times more probable than the inverted ordering. When incorporating a 2D $\mathrm{\Delta }{m}_{32}^2-{\sin }^{2}2{\theta }_{13}$constraint based on Daya Bay data, this preference strengthens to a Bayes factor of 6.6 (87%). 

We report the first search for the flavor-changing neutral-current decays $B\to X_s\nu \overline{\nu }$, where $X_s$is a hadronic system with strangeness equal to 1, in data collected with the Belle II detector at the SuperKEKB asymmetric-energy $e^{+}{e}^{-}$collider. The data sample corresponds to an integrated luminosity of $365{\mathrm{fb}}^{-1}$collected at the $\mathrm{\Upsilon }\left(4S\right)$resonance and $43{\mathrm{fb}}^{-1}$collected at a center-of-mass energy 60 MeV below resonance for estimation of $e^{+}{e}^{-}\to q\overline{q}$continuum background. One of the $B$mesons from the $\mathrm{\Upsilon }\left(4S\right)\to B\overline{B}$decay is fully reconstructed in a hadronic decay mode. The $B\to X_s\nu \overline{\nu }$decay is reconstructed with a sum-of-exclusives approach that uses 30 $X_s$decay modes. This approach provides high sensitivity to the inclusive decay, despite the presence of two undetected neutrinos. The search is performed in three regions of the $X_s$mass, $M_{X_s}^{\mathrm{true}}$, chosen to separate contributions from $K$, $K^{*}\left(892\right)$, and heavier strange final states. We do not observe a significant signal and set upper limits at 90% confidence level on the partial branching fractions for the regions $0.0<M_{X_s}^{\mathrm{true}}<0.6\mathrm{GeV}/c^2$, $0.6<M_{X_s}^{\mathrm{true}}<1.0\mathrm{GeV}/c^2$, and $1.0\mathrm{GeV}/c^2<M_{X_s}^{\mathrm{true}}$of $2.2\times {10}^{-5}$, $9.3\times {10}^{-5}$, and $30.9\times {10}^{-5}$, respectively. Combining the three mass regions, we obtain the upper limit on the branching fraction, $B(B\to X_s\nu \overline{\nu })<3.3\times {10}^{-4}$. 

ABSTRACT SalmonellaOuter Membrane Vesicles (OMVs) were recently shown to inhibit P22 bacteriophage infection. Furthermore, despite there being several published reports now independently describing (1) the marked prevalence of tRFs within secreted vesicle transcriptomes and (2) roles for specific tRFs in facilitating/inhibiting viral replication, there have been no examinations of the effects of vesicle-secreted tRFs on viral infection reported to date. Notably, while specific tRFs have been reported in a number of bacteria, the tRFs expressed by salmonellae have not been previously characterized. As such, we recently screened small RNA-seq datasets for the presence of recurrent, specifically excised tRFs and identified 31 recurrent, relatively abundant tRFs expressed bySalmonella entericaserovar Typhimurium (SL1344). What’s more, we findS. Typhimurium OMVs contain significant levels of tRFs highly complementary to knownSalmonella enterica-infecting bacteriophage with 17 of 31 tRFs bearing marked complementarity to at least one knownSalmonella enterica-infecting phage (averaging 97.4% complementarity over 22.9 nt). Most notably, tRNA-Thr-CGT-1-1, 44-73, bears 100% sequence complementary over its entire 30 nt length to 29 distinct, annotatedSalmonella enterica-infecting bacteriophage including P22. Importantly, we find inhibiting this tRF in secreted OMVs improves P22 infectivity in a dose dependent manner whereas raising OMV tRF levels conversely inhibits P22 infectivity. Furthermore, we find P22 phage pre-incubation with OMVs isolated from naïve, control SL1344S. Typhimurium, successfully rescues the ability ofS. Typhimurium transformed with a specific tRNA-Thr-CGT-1-1, 44-73 tRF inhibitor to defend against P22. Collectively, these experiments confirm tRFs secreted inS. Typhimurium OMVs are directly involved with and required for the ability of OMVs to defend against bacteriophage predation. As we find the majority of OMV tRFs are highly complementary to an array of knownSalmonella enterica-infecting bacteriophage, we suggest OMV tRFs may primarily function as a broadly acting, previously uncharacterized innate antiviral defense. 

We search for the $e^{+}{e}^{-}\to \gamma {\chi }_{bJ}$( $J=0$, 1, 2) processes at center-of-mass energies $\sqrt{s}=10.653$, 10.701, 10.746, and 10.804 GeV. These data were collected with the Belle II detector at the SuperKEKB collider and correspond to 3.5, 1.6, 9.8, and $4.7{\mathrm{fb}}^{-1}$of integrated luminosity, respectively. We set upper limits at the 90% confidence level on the Born cross sections for $e^{+}{e}^{-}\to \gamma {\chi }_{bJ}$at each center-of-mass energy $\sqrt{s}$near 10.746 GeV. The upper limits at 90% confidence level on the Born cross sections for $e^{+}{e}^{-}\to \gamma {\chi }_{b1}$are significantly smaller than the corresponding measured values for $e^{+}{e}^{-}\to \omega {\chi }_{b1}$and $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}\mathrm{\Upsilon }\left(2S\right)$at $\sqrt{s}=10.746\mathrm{GeV}$. 

We present an analysis of the processes $e^{+}{e}^{-}\to \eta \mathrm{\Upsilon }\left(1S\right)$, $\eta \mathrm{\Upsilon }\left(2S\right)$, and $\gamma X_b$with $X_b\to {\pi }^{+}{\pi }^{-}{\chi }_{bJ},{\chi }_{bJ}\to \gamma \mathrm{\Upsilon }\left(1S\right)$( $J=1$, 2) reconstructed from $\gamma \gamma {\pi }^{+}{\pi }^{-}{\ell }^{+}{\ell }^{-}$ $(\ell =e,\mu )$final states in $19.6{\mathrm{fb}}^{-1}$of Belle II data collected at four energy points near the peak of the $\mathrm{\Upsilon }\left(10753\right)$resonance. Here, $X_b$is a hypothetical bottomonium-sector partner of the $X\left(3872\right)$. In the process $e^{+}{e}^{-}\to \eta \mathrm{\Upsilon }\left(2S\right)$, we observe a signal with a significance that exceeds $6.0\sigma$when all energy points are combined. A signal with a significance of $4.2\sigma$is observed at a center-of-mass energy of 10.653 GeV, close to the $B^{*}{\overline{B}}^{*}$threshold. At this energy, we measure $\sigma \left(\eta \mathrm{\Upsilon }\right(2S\left)\right)/\sigma \left({\pi }^{+}{\pi }^{-}\mathrm{\Upsilon }\right(2S\left)\right)>23$at the 90% confidence level, indicating a strong violation of heavy-quark spin symmetry. No significant signal is observed for $e^{+}{e}^{-}\to \eta \mathrm{\Upsilon }\left(1S\right)$or $\gamma X_b$. Upper limits on the Born cross sections for the processes $e^{+}{e}^{-}\to \eta \mathrm{\Upsilon }\left(1S\right)$and $e^{+}{e}^{-}\to \gamma X_b$with $X_b\to {\pi }^{+}{\pi }^{-}{\chi }_{bJ}$are determined. 

Double- and single-differential cross sections for inclusive charged-current ${\nu }_{\mu }$-nucleus scattering are reported for the kinematic domain 0 to $2\mathrm{GeV}/c$in three-momentum transfer and 0 to 2 GeV in available energy, at a mean ${\nu }_{\mu }$energy of 1.86 GeV. The measurements are based on an estimated 995,760 ${\nu }_{\mu }$charged-current (CC) interactions in the scintillator medium of the NOvA Near Detector. The subdomain populated by 2-particle-2-hole (2p2h) reactions is identified by the cross section excess relative to predictions for ${\nu }_{\mu }$-nucleus scattering that are constrained by a data control sample. Models for 2-particle-2-hole processes are rated by ${\chi }^2$comparisons of the predicted-versus-measured ${\nu }_{\mu }$CC inclusive cross section over the full phase space and in the restricted subdomain. Shortfalls are observed in neutrino generator predictions obtained using the theory-based València and SuSAv2 2p2h models. Published by the American Physical Society2025 

We report a search for neutrino oscillations to sterile neutrinos under a model with three active and one sterile neutrinos ( $3+1$model). This analysis uses the NOvA detectors exposed to the NuMI beam, running in neutrino mode. The data exposure, $13.6\times {10}^{20}$protons on target, doubles that previously analyzed by NOvA, and the analysis is the first to use ${\nu }_{\mu }$charged-current interactions in conjunction with neutral-current interactions. Neutrino samples in the near and far detectors are fitted simultaneously, enabling the search to be carried out over a $\mathrm{\Delta }{m}_{41}^2$range extending 2 (3) orders of magnitude above (below) $1{\mathrm{eV}}^2$. NOvA finds no evidence for active-to-sterile neutrino oscillations under the $3+1$model at 90% confidence level. New limits are reported in multiple regions of parameter space, excluding some regions currently allowed by IceCube at 90% confidence level. We additionally set the most stringent limits for anomalous ${\nu }_{\tau }$appearance for $\mathrm{\Delta }{m}_{41}^2\le 3{\mathrm{eV}}^2$. Published by the American Physical Society2025 

Abstract Measuring observables to constrain models using maximum-likelihood estimation is fundamental to many physics experiments. Wilks' theorem provides a simple way to construct confidence intervals on model parameters, but it only applies under certain conditions. These conditions, such as nested hypotheses and unbounded parameters, are often violated in neutrino oscillation measurements and other experimental scenarios. Monte Carlo methods can address these issues, albeit at increased computational cost. In the presence of nuisance parameters, however, the best way to implement a Monte Carlo method is ambiguous. This paper documents the method selected by the NOvA experiment, the profile construction. It presents the toy studies that informed the choice of method, details of its implementation, and tests performed to validate it. It also includes some practical considerations which may be of use to others choosing to use the profile construction. 

Abstract The landmark discovery that neutrinos have mass and can change type (or flavour) as they propagate—a process called neutrino oscillation^1–6—has opened up a rich array of theoretical and experimental questions being actively pursued today. Neutrino oscillation remains the most powerful experimental tool for addressing many of these questions, including whether neutrinos violate charge-parity (CP) symmetry, which has possible connections to the unexplained preponderance of matter over antimatter in the Universe^7–11. Oscillation measurements also probe the mass-squared differences between the different neutrino mass states (Δm²), whether there are two light states and a heavier one (normal ordering) or vice versa (inverted ordering), and the structure of neutrino mass and flavour mixing¹². Here we carry out the first joint analysis of datasets from NOvA¹³and T2K¹⁴, the two currently operating long-baseline neutrino oscillation experiments (hundreds of kilometres of neutrino travel distance), taking advantage of our complementary experimental designs and setting new constraints on several neutrino sector parameters. This analysis provides new precision on the$$\Delta {m}_{32}^{2}$$ $\Delta m_{32}^2$mass difference, finding$$2.4{3}_{-0.03}^{+0.04}\times 1{0}^{-3}\,{{\rm{eV}}}^{2}$$ $2.43_{-0.03}^{+0.04}\times 10^{-3}{\mathrm{eV}}^2$in the normal ordering and$$-2.4{8}_{-0.04}^{+0.03}\times 1{0}^{-3}\,{{\rm{eV}}}^{2}$$ $-2.48_{-0.04}^{+0.03}\times 10^{-3}{\mathrm{eV}}^2$in the inverted ordering, as well as a 3σinterval onδ_CPof [−1.38π, 0.30π] in the normal ordering and [−0.92π, −0.04π] in the inverted ordering. The data show no strong preference for either mass ordering, but notably, if inverted ordering were assumed true within the three-flavour mixing model, then our results would provide evidence of CP symmetry violation in the lepton sector.