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Solar and wind power are now cheaper than fossil fuels but are intermittent. The extra supply-side variability implies growing benefits of using real-time retail pricing (RTP). We evaluate the potential gains of RTP using a model that jointly solves investment, supply, storage, and demand to obtain a chronologically detailed dynamic equilibrium for the island of Oahu, Hawai'i. We find that RTP reduces costs in high-renewable systems by roughly 6 to 12 times as much as in fossil systems holding demand assumptions fixed, markedly lowering the cost of clean energy integration.

In semiconductors, exciton or charge carrier diffusivity is typically described as an inherent material property. Here, we show that the transport of excitons among CsPbBr₃ perovskite nanocrystals (NCs) depends markedly on how recently those NCs were occupied by a previous exciton. Using transient photoluminescence microscopy, we observe a striking dependence of the apparent exciton diffusivity on excitation laser power that does not arise from nonlinear exciton-exciton interactions or thermal heating. We interpret our observations with a model in which excitons cause NCs to transition to a long-lived metastable configuration that markedly increases exciton transport. The exciton diffusivity observed here (>0.15 square centimeters per second) is considerably higher than that observed in other NC systems, revealing unusually strong excitonic coupling between NCs. The finding of a persistent enhancement in excitonic coupling may help explain other photophysical behaviors observed in CsPbBr₃ NCs, such as superfluorescence, and inform the design of optoelectronic devices. Science Advances, 10 (8) ISSN:2375-2548

Nonlinear AC Optimal Power Flow (OPF) problems are commonly approximated by linearized DC OPF problems to obtain real power solutions for restructured wholesale power markets. We first present a standard DC OPF problem, which has the numerically desirable form of a strictly convex quadratic programming (SCQP) problem when voltage angles are eliminated by substitution. We next augment this standard DC OPF problem in a physically meaningful way, still retaining an SCQP form, so that solution values for voltage angles and locational marginal prices are directly obtained along with real power injections and branch flows. We then show how this augmented DC OPF problem can be solved using QuadProgJ, an open-source Java SCQP solver newly developed by the authors that implements the well-known dual active-set SCQP algorithm by Goldfarb and Idnani (1983). To demonstrate the accuracy of QuadProgJ, comparative results are reported for a well-known suite of numerical QP test cases with up to 1500 decision variables plus constraints. Detailed QuadProgJ results are also reported for 3-node and 5-node DC OPF test cases taken from power systems texts and ISO-NE/MISO/PJM training manuals. Replaced with revised version of paper 06/21/06.

The Forward Search Experiment (FASER) at CERN’s Large Hadron Collider (LHC) has recently directly detected the first collider neutrinos. Neutrinos play an important role in all FASER analyses, either as signal or background, and it is therefore essential to understand the neutrino event rates. In this study, we update previous simulations and present prescriptions for theoretical predictions of neutrino fluxes and cross sections, together with their associated uncertainties. With these results, we discuss the potential for possible measurements that could be carried out in the coming years with the FASER neutrino data to be collected in LHC Run 3 and Run 4. Physical review / D 110(1), 012009 (2024). doi:10.1103/PhysRevD.110.012009 Published by American Physical Society, Ridge, NY

We report measurements of the $e^+e^- \to B\bar{B}$, $B\bar{B}{}^*$, and $B^*\bar{B}{}^*$ cross sections at four energies, 10653, 10701, 10746 and 10805 MeV, using data collected by the Belle~II experiment. We reconstruct one $B$ meson in a large number of hadronic final states and use its momentum to identify the production process. In the first $2-5$ MeV above $B^*\bar{B}{}^*$ threshold, the $e^+e^- \to B^*\bar{B}{}^*$ cross section increases rapidly. This may indicate the presence of a pole close to the threshold. 30 pages, 15 figures, version accepted by JHEP

We report a measurement of the $e^+e^- \to π^+π^-π^0$ cross section in the energy range from 0.62 to 3.50 GeV using an initial-state radiation technique. We use an $e^+e^-$ data sample corresponding to 191 $\text{fb}^{-1}$ of integrated luminosity, collected at a center-of-mass energy at or near the $Υ{(4S)}$ resonance with the Belle II detector at the SuperKEKB collider. Signal yields are extracted by fitting the two-photon mass distribution in $e^+e^- \to π^+π^-π^0γ$ events, which involve a $π^0 \to γγ$ decay and an energetic photon radiated from the initial state. Signal efficiency corrections with an accuracy of 1.6% are obtained from several control data samples. The uncertainty on the cross section at the $ω$ and $ϕ$ resonances is dominated by the systematic uncertainty of 2.2%. The resulting cross sections in the 0.62-1.80 GeV energy range yield $ a_μ^{3π} = [48.91 \pm 0.23~(\mathrm{stat}) \pm 1.07~(\mathrm{syst})] \times 10^{-10} $ for the leading-order hadronic vacuum polarization contribution to the muon anomalous magnetic moment. This result differs by $2.5$ standard deviations from the most precise current determination. 23 pages, 24 figures, submitted to PRD

Aim Species distribution models (SDMs) are widely used to make predictions on how species distributions may change as a response to climatic change. To assess the reliability of those predictions, they need to be critically validated with respect to what they are used for. While ecologists are typically interested in how and where distributions will change, we argue that SDMs have seldom been evaluated in terms of their capacity to predict such change. Instead, typical retrospective validation methods estimate model's ability to predict to only one static time in future. Here, we apply two validation methods, one that predicts and evaluates a static pattern, while the other measures change and compare their estimates of predictive performance. Location Fennoscandia. Methods We applied a joint SDM to model the distributions of 120 bird species in four model validation settings. We trained models with a dataset from 1975 to 1999 and predicted species' future occurrence and abundance in two ways: for one static time period (2013–2016, ‘static validation’) and for a change between two time periods (difference between 1996–1999 and 2013–2016, ‘change validation’). We then measured predictive performance using correlation between predicted and observed values. We also related predictive performance to species traits. Results Even though static validation method evaluated predictive performance as good, change method indicated very poor performance. Predictive performance was not strongly related to any trait. Main Conclusions Static validation method might overestimate predictive performance by not revealing the model's inability to predict change events. If species' distributions remain mostly stable, then even an unfit model can predict the near future well due to temporal autocorrelation. We urge caution when working with forecasts of changes in spatial patterns of species occupancy or abundance, even for SDMs that are based on time series datasets unless they are critically validated for forecasting such change. peerReviewed

This dataset contains the spring and autumn migration phenology dataset used in Haest et al. (2020) to determine the drivers of migration phenology of Brazilian free-tailed bats at Bracken Cave (USA) over the period 1995-2017. The phenology dataset was derived from nightly colony population sizes estimated using weather radar data (Stepanian et al., 2018). See the Materials and Methods section in Haest et al. (2020) for more details on the dataset. References: Haest, B., Stepanian, P. M., Wainwright, C. E., Liechti, F., & Bauer, S. (2021). Climatic drivers of (changes in) bat migration phenology at Bracken Cave (USA). Global Change Biology, 27(4), 768-780. https://doi.org/10.1111/gcb.15433 Stepanian, P. M., & Wainwright, C. E. (2018). Ongoing changes in migration phenology and winter residency at Bracken Bat Cave. Global Change Biology, 24(7), 3266–3275. https://doi.org/10.1111/gcb.14051