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This is a work-in-progress paper. The flipped classroom (FC) model is a well established teaching strategy dating to 1970’s practices in the Soviet Union. FC has two decades of use in post-secondary education since it was proposed by Lage et al. However, breaking studies find no academic improvement with FC model among minority students. Rather, it distances at-risk students. Indeed, certain demographics prefer authoritative over dialogic instruction style. We are motivated to determine FCs effectiveness with students at a medium-sized Hispanic Serving Institution (HSI) and Minority Serving Institution (MSI). For one of our NSF grant activities, we piloted two variations of the flipped classroom model. The key idea is that literature finds that FC classes need better regulation of underperforming students. Generally, the FC models in our work included peer-instruction, active learning, recorded lectures, and pre-assessment quizzes. There were no post-assessment assignments or traditional homework. Some sections employed Just-in-Time-Teaching, and careful selection of groups according to skill (within-class homogenous grouping). Other sections experimented with diversity and inclusion-based grouping and project-based learning. Students at the university are non-traditional, a term used to describe individuals who meet some of the following criteria: having a significant gap between post-secondary education and high-school graduation, being financially independent from their parents, having dependents, and working twenty or more hours per week. 60% of the individuals at our campus are Pell eligible. We study an intersectional inequality: wage-based work is disinclined to accommodate students attending lecture during the work day, and minorities may not prefer dialogic instruction. We analyze student attitudes since Fall 2020, among tens of class sections and hundreds of students. Class sections in the study are upper-division core courses in Computer Science, Computer Engineering and Electrical Engineering. Data is collected from mostly online sections during the COVID-19 pandemic. A pre- and post-surveys were administered collecting demographic information and student attitudes. Hispanic/Latino(a) students found videos to be a complete study medium—that it was not required to seek out third-party materials to prepare for class. They found the class to be more engaging, and self-identified that they could identify previous concepts important to the task at hand. Results were surprising because there were no statistically significant differences with a general population’s exposure to FC. Hispanic/Latino(a)s find the FC model described in our work engaging and effective. 

The high-energy radiative output, from the X-ray to the ultraviolet, of exoplanet host stars drives photochemical reactions and mass loss in the upper regions of planetary atmospheres. In order to place constraints on the atmospheric properties of the three closest terrestrial exoplanets transiting M dwarfs, we observe the high-energy spectra of the host stars LTT 1445A and GJ 486 in the X-ray withXMM-NewtonandChandraand in the ultraviolet with HST/COS and STIS. We combine these observations with estimates of extreme-ultraviolet flux, reconstructions of the Lyαlines, and stellar models at optical and infrared wavelengths to produce panchromatic spectra from 1 Å to 20 µm for each star. While LTT 1445Ab, LTT 1445Ac, and GJ 486b do not possess primordial hydrogen-dominated atmospheres, we calculate that they are able to retain pure CO₂atmospheres if starting with 10, 15, and 50% of Earth’s total CO₂budget, respectively, in the presence of their host stars’ stellar wind. We use age-activity relationships to place lower limits of 2.2 and 6.6 Gyr on the ages of the host stars LTT 1445A and GJ 486. Despite both LTT 1445A and GJ 486 appearing inactive at optical wavelengths, we detect flares at ultraviolet and X-ray wavelengths for both stars. In particular, GJ 486 exhibits two far-ultraviolet flares with absolute energies of 10^29.5and 10^30.1erg (equivalent durations of 4357 ± 96 and 19 724 ± 169 s) occurring 3 h apart. Based on the timing of the observations, we suggest that these high-energy flares are related and indicative of heightened flaring activity that lasts for a period of days, but our interpretations are limited by sparse time-sampling. Consistent high-energy monitoring is needed to determine the duration and extent of high-energy activity on individual M dwarfs and the population as a whole. 

Abstract The recent IceCube detection of TeV neutrino emission from the nearby active galaxy NGC 1068 suggests that active galactic nuclei (AGNs) could make a sizable contribution to the diffuse flux of astrophysical neutrinos. The absence of TeVγ-rays from NGC 1068 indicates neutrino production in the vicinity of the supermassive black hole, where the high radiation density leads toγ-ray attenuation. Therefore, any potential neutrino emission from similar sources is not expected to correlate with high-energyγ-rays. Disk-corona models predict neutrino emission from Seyfert galaxies to correlate with keV X-rays because they are tracers of coronal activity. Using through-going track events from the Northern Sky recorded by IceCube between 2011 and 2021, we report results from a search for individual and aggregated neutrino signals from 27 additional Seyfert galaxies that are contained in the Swift's Burst Alert Telescope AGN Spectroscopic Survey. Besides the generic single power law, we evaluate the spectra predicted by the disk-corona model assuming stochastic acceleration parameters that match the measured flux from NGC 1068. Assuming all sources to be intrinsically similar to NGC 1068, our findings constrain the collective neutrino emission from X-ray bright Seyfert galaxies in the northern sky, but, at the same time, show excesses of neutrinos that could be associated with the objects NGC 4151 and CGCG 420-015. These excesses result in a 2.7σsignificance with respect to background expectations. 

We report a study of the inelasticity distribution in the scattering of neutrinos of energy 80–560 GeV off nucleons. Using atmospheric muon neutrinos detected in IceCube’s sub-array DeepCore during 2012–2021, we fit the observed inelasticity in the data to a parameterized expectation and extract the values that describe it best. Finally, we compare the results to predictions from various combinations of perturbative QCD calculations and atmospheric neutrino flux models. Published by the American Physical Society2025 

Abstract The nature of dark matter remains unresolved in fundamental physics. Weakly Interacting Massive Particles (WIMPs), which could explain the nature of dark matter, can be captured by celestial bodies like the Sun or Earth, leading to enhanced self-annihilation into Standard Model particles including neutrinos detectable by neutrino telescopes such as the IceCube Neutrino Observatory. This article presents a search for muon neutrinos from the center of the Earth performed with 10 years of IceCube data using a track-like event selection. We considered a number of WIMP annihilation channels ($$\chi \chi \rightarrow \tau ^+\tau ^-$$ $\chi \chi \to {\tau }^{+}{\tau }^{-}$/$$W^+W^-$$ $W^{+}{W}^{-}$/$$b\bar{b}$$ $b\overline{b}$) and masses ranging from 10 GeV to 10 TeV. No significant excess over background due to a dark matter signal was found while the most significant result corresponds to the annihilation channel$$\chi \chi \rightarrow b\bar{b}$$ $\chi \chi \to b\overline{b}$for the mass$$m_{\chi }=250$$ $m_{\chi }=250$ GeV with a post-trial significance of$$1.06\sigma $$ $1.06\sigma$. Our results are competitive with previous such searches and direct detection experiments. Our upper limits on the spin-independent WIMP scattering are world-leading among neutrino telescopes for WIMP masses$$m_{\chi }>100$$ $m_{\chi }>100$ GeV. 

Abstract Active galactic nuclei (AGN) are promising candidate sources of high-energy astrophysical neutrinos, since they provide environments rich in matter and photon targets where cosmic-ray interactions may lead to the production of gamma rays and neutrinos. We searched for high-energy neutrino emission from AGN using the Swift-BAT Spectroscopic Survey catalog of hard X-ray sources and 12 yr of IceCube muon track data. First, upon performing a stacked search, no significant emission was found. Second, we searched for neutrinos from a list of 43 candidate sources and found an excess from the direction of two sources, the Seyfert galaxies NGC 1068 and NGC 4151. We observed NGC 1068 at flux ${\varphi }_{{\nu }_{\mu }+{\overline{\nu }}_{\mu }}$= $4.02_{-1.52}^{+1.58}\times 10^{-11}$TeV⁻¹cm⁻²s⁻¹normalized at 1 TeV, with a power-law spectral indexγ= 3.10 ${}_{-0.22}^{+0.26}$, consistent with previous IceCube results. The observation of a neutrino excess from the direction of NGC 4151 is at a posttrial significance of 2.9σ. If interpreted as an astrophysical signal, the excess observed from NGC 4151 corresponds to a flux ${\varphi }_{{\nu }_{\mu }+{\overline{\nu }}_{\mu }}$= $1.51_{-0.81}^{+0.99}\times 10^{-11}$TeV⁻¹cm⁻²s⁻¹normalized at 1 TeV andγ= 2.83 ${}_{-0.28}^{+0.35}$. 

Abstract We report a search for high-energy astrophysical neutrino multiplets, detections of multiple neutrino clusters in the same direction within 30 days, based on an analysis of 11.4 yr of IceCube data. A new search method optimized for transient neutrino emission with a monthly timescale is employed, providing a higher sensitivity to neutrino fluxes. This result is sensitive to neutrino transient emission, reaching per-flavor flux of approximately $10^{-10}\mathrm{erg}{\mathrm{cm}}^{-2}{\mathrm{s}}^{-1}$from the Northern Sky in the energy rangeE ≳ 50 TeV. The number of doublets and triplets identified in this search is compatible with the atmospheric background hypothesis, which leads us to set limits on the nature of neutrino transient sources with emission timescales of one month. 

Abstract We analyzed the 7.92 × 10¹¹cosmic-ray-induced muon events collected by the IceCube Neutrino Observatory from 2011 May 13, when the fully constructed experiment started to take data, to 2023 May 12. This data set provides an up-to-date cosmic-ray arrival direction distribution in the Southern Hemisphere with unprecedented statistical accuracy covering more than a full period length of a solar cycle. Improvements in Monte Carlo event simulation and better handling of year-to-year differences in data processing significantly reduce systematic uncertainties below the level of statistical fluctuations compared to the previously published results. We confirm the observation of a change in the angular structure of the cosmic-ray anisotropy between 10 TeV and 1 PeV, more specifically in the 100–300 TeV energy range. For the first time, we analyzed the angular power spectrum at different energies. The observed variations of the power spectra with energy suggest relatively reduced large-scale features at high energy compared to those of medium and small scales. The large volume of data enhances the statistical significance at higher energies, up to the PeV scale, and smaller angular scales, down to approximately 6° compared to previous findings.