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Collisionless plasma systems are often studied using fully kinetic simulations, where protons and electrons are treated as particles. Due to their computational expense, it is necessary to reduce the ion-to-electron mass ratio $m_i/m_e$or the ratio between plasma and cyclotron frequencies in simulations of large systems. In this Letter we show that when electron-scale waves are present in larger-scale systems, numerical parameters affect their amplitudes and effects on the larger system. Using lower-hybrid drift waves during magnetic reconnection as an example, we find that the ratio between the wave electric field and the reconnection electric field scales as $\sqrt{m_i/m_e}$, while the phase relationship is also affected. The combination of these effects means that the anomalous drag that contributes to momentum balance in the reconnection region can be underestimated by an order of magnitude. The results are relevant to the coupling of electron-scale waves to ion-scale reconnection regions, and other systems such as collisionless shocks. Published by the American Physical Society2024 

Laboratory experience is among the key components in engineering education. It is highly instrumental and plays a significant role in students’ knowledge building, application, and distribution. Learning in laboratories is interactive and often collaborative. On the other hand, students, who learn engineering through online mechanisms, may face challenges with labs, which were frequently documented during the recent pandemic. To address such challenges, innovative online lab learning modules were developed, and learning strategies were implemented in five courses in electrical engineering, Circuits I, Electronics I, Electronics II, Signals and Systems, and Embedded System, through which students gain solid foundation before advancing to senior design projects. The two main incorporated strategies were Open-Ended lab design and Teamwork implementation. Open-Ended lab modules using a lab-in-a-box approach allow students solving lab problems with multiple approaches fostering problem solving both independently and collaboratively. This innovative lab design promotes problem solving at various cognitive levels. It is better suited for concept exploration and collaborative lab learning environments as opposed to the traditional lab works with a prescribed approach leading students to follow certain procedures that may lack the problem exploration stage. Additionally, course instructors formed online lab groups, so that students were sharing the problem-solving process – from ideas formation to solutions – with their peers. To evaluate the effectiveness of the implemented lab strategies, students in the participating courses were randomly divided into experimental and control groups. Both assignment grades and students' feedback via surveys were used to evaluate students' learning. Participants in the control group were learning in labs through the materials that were aligned with core concepts by following predetermined procedures. Students in the experimental group learned through inquiry-based lab materials that required them to work in teams by integrating core concepts together to find a solution and while following one of potentially many approaches. To maximize the online lab learning effect and to replicate the contemporary industry, commerce, and research practices, instructor-structured cooperative learning strategies were applied along with pre-lab simulations and instructional videos. This paper showcases the outcomes of our 2nd year implementation of active learning laboratory strategies on the mixed population of online and face-to-face students. We observed that students in the experimental group generally outperformed their counterparts in labs and showed significantly higher results in the assignments addressing more advanced concept understanding and applications (grand average of 88.3% vs. 66.3%). Surveys also indicated that students saw the benefits of collaboration with Open-Ended lab modules not only for learning concepts, but also for improving their communication skills. Students were able to collaborate on lab problems through various communication tools, such as course Learning Management System (LMS) and mobile apps forming online learning communities. We believe that that the implementation of open-ended collaborative laboratory strategies can assist students in cultivating a deeper comprehension, fostering self-confidence, and refining their critical thinking abilities, all while strengthening their sense of inclusion within the field of engineering. 

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 

Many researchers have identified the need for a more holistic understanding of the role of feedback in supporting learning in online environments. This study explores how our design, development, and implementation of an online feedback facilitation system influenced high school science teachers’ learning in an asynchronous teacher professional development online course. We then describe teachers’ and facilitators’, i.e., feedback providers’, perceptions of the effectiveness of the system’s features for supporting participants’ learning and engagement. Our work also responds to recent calls for developing a more nuanced understanding of how the complexity of feedback influences learning and the need for more qualitative research on online facilitators’ and learners’ experiences working with new technologies. Results demonstrated that, despite the difficulty of analyzing the complex variables influencing learners’ interactions and perceptions of the feedback system, designing adaptive feedback systems that draw on the principles of design- based implementation research (DBIR) offer promise for enhancing the systems’ contributions to teacher learning. 

We consider the potential for a 10 kg undoped cryogenic CsI detector operating at the Spallation Neutron Source to measure coherent elastic neutrino-nucleus scattering and its sensitivity to discover new physics beyond the standard model (BSM). Through a combination of increased event rate, lower threshold, and good timing resolution, such a detector would significantly improve on past measurements. We considered tests of several BSM scenarios such as neutrino nonstandard interactions and accelerator-produced dark matter. This detector’s performance was also studied for relevant questions in nuclear physics and neutrino astronomy, namely the weak charge distribution of Cs and I nuclei and detection of neutrinos from a core-collapse supernova. Published by the American Physical Society2024 

Abstract Despite the f₀(980) hadron having been discovered half a century ago, the question about its quark content has not been settled: it might be an ordinary quark-antiquark ($${{\rm{q}}}\overline{{{\rm{q}}}}$$ $q\overline{q}$) meson, a tetraquark ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{q}}}\overline{{{\rm{q}}}}$$ $q\overline{q}q\overline{q}$) exotic state, a kaon-antikaon ($${{\rm{K}}}\overline{{{\rm{K}}}}$$ $K\overline{K}$) molecule, or a quark-antiquark-gluon ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{g}}}$$ $q\overline{q}g$) hybrid. This paper reports strong evidence that the f₀(980) state is an ordinary$${{\rm{q}}}\overline{{{\rm{q}}}}$$ $q\overline{q}$meson, inferred from the scaling of elliptic anisotropies (v₂) with the number of constituent quarks (n_q), as empirically established using conventional hadrons in relativistic heavy ion collisions. The f₀(980) state is reconstructed via its dominant decay channel f₀(980) →π⁺π⁻, in proton-lead collisions recorded by the CMS experiment at the LHC, and itsv₂is measured as a function of transverse momentum (p_T). It is found that then_q= 2 ($${{\rm{q}}}\overline{{{\rm{q}}}}$$ $q\overline{q}$state) hypothesis is favored overn_q= 4 ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{q}}}\overline{{{\rm{q}}}}$$ $q\overline{q}q\overline{q}$or$${{\rm{K}}}\overline{{{\rm{K}}}}$$ $K\overline{K}$states) by 7.7, 6.3, or 3.1 standard deviations in thep_T< 10, 8, or 6 GeV/cranges, respectively, and overn_q= 3 ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{g}}}$$ $q\overline{q}g$hybrid state) by 3.5 standard deviations in thep_T< 8 GeV/crange. This result represents the first determination of the quark content of the f₀(980) state, made possible by using a novel approach, and paves the way for similar studies of other exotic hadron candidates.