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Previous research has shown that female and Hispanic students who are underrepresented in science, technology, engineering and mathematics (STEM) face more educational barriers than their non-Hispanic, male peers. However, little research has been conducted on the effects of intersectional identities in the STEM space. In an effort to bridge the gap in underrepresented students' experience, the PSEG Institute for Sustainability Studies organizes a paid, interdisciplinary, team-based, experiential learning and internship program called the Green Teams that occurs during 10 weeks of the summer. The Green Teams Program strives to provide undergraduate students from all backgrounds–academically, economically, and demographically–an opportunity to develop their abilities in STEM fields and prepare them to enter the professional world. Based upon a survey given post-internship, self-reported learning gains for all students were analyzed to determine if the program had a significantly greater impact on students who are from groups traditionally underrepresented in STEM in their STEM-related learning gains and their confidence in STEM disciplines. Through t-tests, a Principal Component Analysis (PCA), and a 2-way factorial Analysis of Variance (ANOVA), Hispanic and female participants were found to report significantly higher learning gains than their counterparts in multiple STEM areas from increased tolerance for obstacles to gains in self confidence. The results of the study suggest Hispanic and female students benefit from paid work experiences in STEM with diverse peers and intentional, supportive mentoring. This research on the Green Teams Program provides insight into how this approach positively impacts STEM education of individuals from traditionally underrepresented groups in STEM. The findings may help to further guide the development of the Green Teams Program and the adoption of paid, interdisciplinary, team-based, experiential learning and internship experiences in additional academic STEM settings. 

A study of the dead layer thickness and quenching factor of a plastic scintillator for use in ultracold neutron (UCN) experiments is described. Alpha spectroscopy was used to determine the thickness of a thin surface dead layer to be 630 ± 110 nm. The relative light outputs from the decay of 241Am and Compton scattering of electrons were used to extract Birks’ law coefficient, yielding a kB value of 0.087 ± 0.003 mm/MeV, consistent with some previous reports for other polystyrene-based scintillators. The results from these measurements are incorporated into the simulation to show that an energy threshold of (∼9 keV) can be achieved for the UCNProBe experiment. This low threshold enables high beta particle detection efficiency and the indirect measurement of UCN. The ability to make the scintillator deuterated, accompanied by its relatively thin dead layer, gives rise to unique applications in a wide range of UCN experiments, where it can be used to trap UCN and detect charged particles in situ. 

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 

Abstract The Gulf of Maine and surrounding western North Atlantic shelf are some of the fastest warming regions of the worlds oceans. The lack of long-term observational records from this area inhibits the ability to assess the timing and initial causes of this warming and consequently accurately predict future changes to this ecologically and economically important region. Here we present oxygen, nitrogen, and radiocarbon isotope data measured in Arctica islandica shells collected in the western North Atlantic to better understand the past temperature and ocean circulation variability of the region over the last 300 years. We combine these results with output from the Community Earth System Model Last Millennium Ensemble simulations to assess the temporal and spatial context of these isotope records. We find that the isotope records capture the end and reversal of a millennium-scale cooling trend in the Gulf of Maine. Last Millennium Ensemble single-forcing simulations indicate that this cooling trend appears to be largely driven by volcanic forcing. The nitrogen and radiocarbon records indicate that ocean circulation is in part driving the reconstructed hydrographic changes, pointing to a potential role of the Atlantic Meridional Overturning Circulation in regulating Gulf of Maine temperatures as suggested by the Last Millennium Ensemble simulations. Both isotope and model results suggest that the Gulf of Maine began to warm in the late 19th century, ultimately driven by increased greenhouse gas forcing. Plain-language Summary The Gulf of Maine, located off of the Eastern Coast of the United States, has experienced significant temperature increases recently. Because the instrumental record only began in 1905, we do not have a good idea of when this warming began and what may have initially caused the warming. Here, we analyze the chemistry of clam shells, which have grown in the Gulf of Maine for hundreds of years, to infer past changes in ocean temperatures and water properties. We combine these results with output from a climate model to reveal that the temperatures reconstructed from the clams shells agree well with the model during the period of overlap. Both the chemical records and the model suggest the Gulf of Maine started warming in the late 1800s as a result of increased atmospheric greenhouse gas concentrations. Before this warming began, the Gulf of Maine region appears to have been cooling. The model suggests that this cooling trend is likely due to the influence of volcanic eruptions. The chemical records from the clam shells also suggest that part of this cooling is likely related to changing ocean circulation patterns. 

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 

Different approaches to operationalizing the cultural theory (CT) developed by Douglas, Thompson, Wildavsky, and others in survey research on risk perceptions are rarely compared, never for the same people. We compare for US respondents the construct validity of cultural worldview measures developed by Jenkins-Smith and colleagues—including both indices of items refining the Wildavsky and Dake approach, and short paragraphs (cultural “statements”)—to those developed by Kahan and colleagues based on cultural cognition theory (CCT). Correlational analyses reveal moderate convergent and discriminant validity among these measures, and along with regression analyses controlling for demographic variables similarly moderate predictive validity across measures for judgments of personal risk for ten hazards. CT statements better discriminate between individualists and hierarchists, and CT indices explain more variance in judged risk (predictive validity) when controlling for demographic variables in regression analyses. We discuss theoretical and methodological implications of our findings to foster further scholarly comparisons of and improvements in these survey-based cultural approaches to explaining risk judgments.