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We report the first detection of coherent elastic neutrino-nucleus scattering (CEvNS) on natural germanium, measured at the Spallation Neutron Source at Oak Ridge National Laboratory. The Ge-Mini detector of the COHERENT collaboration employs large-mass, low-noise, high-purity germanium spectrometers, enabling excellent energy resolution, and an analysis threshold of 1.5 keV electron-equivalent ionization energy. We observe an on-beam excess of ${20.6}_{-6.3}^{+7.1}$counts with a total exposure of 10.22 GWhkg, and we reject the no-CEvNS hypothesis with $3.9\sigma$significance. The result agrees with the predicted standard model of particle physics signal rate within $2\sigma$. Published by the American Physical Society2025 

We investigate the state-of-the-art Lanczos eigensolvers available in the Grid and QUDA libraries. They include Implicitly Restarted Lanczos, Thick-Restart Lanczos, and Block Lanczos. We measure and analyze their performance for the Highly Improved Staggered Quark (HISQ) Dirac operator. We also discuss optimization of Chebyshev acceleration. 

Abstract On 11 September 2021, two small thunderstorms developed over the Telescope Array Surface Detector (TASD) that produced an unprecedented number of six downward terrestrial gamma ray flashes (TGFs) within one‐hour timeframe. The TGFs occurred during the initial stage of negative cloud‐to‐ground flashes whose return strokes had increasingly large peak currents up to 223 kA, 147 GeV energy deposit in up to 25 1.2 km‐spaced surface detectors, and intermittent bursts of gamma‐rays with total durations up to 717 s. The analyses are based on observations recorded by the TASD network, complemented by data from a 3D lightning mapping array, broadband VHF interferometer, fast electric field change sensor, high‐speed video camera, and the National Lightning Detection Network. The TGFs of the final two flashes had gamma fluences of and 8, logarithmically bridging the gap between previous TASD and satellite‐based detections. The observations further emphasize the similarity between upward and downward TGF varieties, suggesting a common mechanism for their production. 

Abstract. We investigated preservice teachers’ (PSTs) (N=13) experiences in a science teaching inquiry group professional learning experience on integrating computational thinking (CT) into elementary science. A subgroup of PSTs (n=6) participated alongside their mentor teachers. The others (n=7) participated independently. Our research question was: To what extent, if any, did participating in a professional learning experience on CT along with their mentor teachers appear to enhance PSTs’ learning and practice related to CT integration? We analyzed evaluation feedback, interviews, participant-developed lesson plans, surveys, and attendance data. Findings suggested that participants in both groups reacted positively to the learning experience’s content and approach, and expressed similar perceptions of their CT integration knowledge. PSTs participating with their mentor teachers felt slightly more successful in their CT integration efforts, and perceived CT integration as more feasible in their teaching contexts. However, differences between the groups were minimal. We also noted possible of influence of PSTs’ perceptions of the districts in which they were teaching. Our findings underscore the importance of PSTs’ perceptions of their teaching contexts when bringing a new innovation to the classroom - namely, perceptions of their mentors and curricula as supportive of the innovation. Through this ongoing work, we seek to identify empirically-supported strategies for preparing PSTs to integrate CT into their future classrooms.