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A rain-on-snow event in June 2022 led to extreme flooding in northern Yellowstone National Park (YNP). Extensive erosion and overbank deposition altered stream morphology and destroyed park infrastructure including campgrounds, facilities, and roadways. In northern Yellowstone, the previous flood of record was in 1918. The aim of this project is to compare the magnitude of the 1918 flood with the 2022 flooding event. We studied the Lamar River (LR), Soda Butte Creek (SBC), and Pebble Creek (PC) in the summer of 2023. These reaches are the same reaches used by Meyer (2001) to estimate the 1918 peak discharge. Pebble Creek and Soda Butte Creek are tributaries of the Lamar River, which has its headwaters in northern YNP. The reach of the Lamar River surveyed was upstream of the confluence with Pebble Creek and Soda Butte Creek. We used cm-scale RTK GPS to survey channel cross-sections and stage indicators. We used an acoustic doppler velocimeter to calculate current discharge to estimate channel roughness. We then reconstructed the 2022 peak discharges in HEC-RAS. Our models produced estimated peak discharges of 80-90 m3/s at PC, 120-170 m3/s at SBC, and 104-172 m3/s at the LR. Meyer (2001) estimated the peak discharge of the 1918 flood to be 55-75 m3/s at PC, 110-260 m3/s at SBC, and 450-550 m3/s at LR. Based on these estimates, the 2022 peak discharges in PC and SBC exceed those of the 1918 flood, making it the new flood of record on those reaches. The 2022 LR peak discharge, however, was lower than the 1918 estimate. This could be attributed to lower precipitation and less snowmelt in the Lamar Basin that drains the northern Absaroka Range relative to the basins of Pebble Creek and Soda Butte Creek that drain the Beartooth Range. Late spring and early summer rain-on-snow events that cause extreme flooding are likely to occur more frequently in the future because of climate change. Considering the lower relative precipitation in the Lamar Basin during the 2022 flooding, there is potential for greater magnitude flooding in the future during more spatially extensive rain-on-snow events that would increase runoff in the Lamar drainage. 

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 

National discourse about STEM careers has dominated conversations about the need to meet the demands of the labor market. The ever increasing population diversity requires the participation of underrepresented groups, including women and individuals from racially minoritized backgrounds. However, for those at the intersections of historical and persistent marginality, such as Black female students, access to STEM majors, programs, and careers are particularly limited. This article uses observations, four student focus groups, document analysis, and survey data from a Black science conference to understand the experiences of Black women student attendees. Through an intersectional lens, we find that professional conferences can better serve Black female student participants by considering their nuanced experiences, barriers, and contributions to the field. 

This Letter reports a search for charge-parity ( $CP$) symmetry violating nonstandard interactions (NSI) of neutrinos with matter using the NOvA Experiment, and examines their effects on the determination of the standard oscillation parameters. Data from ${\nu }_{\mu }\left({\overline{\nu }}_{\mu }\right)\to {\nu }_{\mu }\left({\overline{\nu }}_{\mu }\right)$and ${\nu }_{\mu }\left({\overline{\nu }}_{\mu }\right)\to {\nu }_e\left({\overline{\nu }}_e\right)$oscillation channels are used to measure the effect of the NSI parameters ${ϵ}_{e\mu }$and ${ϵ}_{e\tau }$. With 90% CL the magnitudes of the NSI couplings are constrained to be $\left|{ϵ}_{e\mu }\right|\lesssim 0.3$and $\left|{ϵ}_{e\tau }\right|\lesssim 0.4$. A degeneracy at $\left|{ϵ}_{e\tau }\right|\approx 1.8$is reported, and we observe that the presence of NSI limits sensitivity to the standard $CP$phase ${\delta }_{CP}$. Published by the American Physical Society2024 

NOvA is a long-baseline neutrino oscillation experiment that measures oscillations in charged-current ${\nu }_{\mu }\to {\nu }_{\mu }$(disappearance) and ${\nu }_{\mu }\to {\nu }_e$(appearance) channels, and their antineutrino counterparts, using neutrinos of energies around 2 GeV over a distance of 810 km. In this work we reanalyze the dataset first examined in our previous paper [] using an alternative statistical approach based on Bayesian Markov chain Monte Carlo. We measure oscillation parameters consistent with the previous results. We also extend our inferences to include the first NOvA measurements of the reactor mixing angle ${\theta }_{13}$, where we find $0.071\le {\sin }^{2}2{\theta }_{13}\le 0.107$, and the Jarlskog invariant, where we observe no significant preference for the $CP$-conserving value $J=0$over values favoring $CP$violation. We use these results to examine the effects of constraints from short-baseline measurements of ${\theta }_{13}$using antineutrinos from nuclear reactors when making NOvA measurements of ${\theta }_{23}$. Our long-baseline measurement of ${\theta }_{13}$is shown to be consistent with the reactor measurements, supporting the general applicability and robustness of the Pontecorvo-Maki-Nakagawa-Sakata framework for neutrino oscillations. Published by the American Physical Society2024