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1. Scattering of larger molecules – part 1: general discussion

   https://doi.org/10.1039/D4FD90019G  

   Babikov, Dmitri; Balucani, Nadia; Bergeat, Astrid; Brouard, Mark; Chandler, David W; Costen, Matthew L; Fárník, Michal; Guo, Hua; Győri, Tibor; Heard, Dwayne; et al (August 2024, Faraday Discussions)
2. I=1 $$\pi$$-$$\pi$$ scattering at the physical point

   https://doi.org/10.22323/1.396.0551  

   Paul, Srijit; Hanlon, Andrew; Hörz, Ben; Mohler, Daniel; Morningstar, Colin; Wittig, Hartmut (May 2022, Pos proceedings of science)

   We present a preliminary analysis of I = 1 π π scattering at the physical point. We make use of the stochastic variant of the distillation framework (also known as sLapH) to compute the relevant two-point correlation matrices using a basis of single and multihadron interpolating operators to estimate the low energy spectra. We perform the Lüscher analysis to determine the scattering phase shift which is finding good agreement with the experimentally obtained phase shifts. 

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3. D meson -- pion scattering on CLS 2+1 flavor ensembles

   https://doi.org/10.22323/1.430.0068  

   Mohler, Daniel; Bulava, John; Hoerz, Ben; Johnson, Christopher; Morningstar, Colin; Hudspith, Renwick J. (February 2023, Proceedings of Science)

   We report progress on finite-volume determinations of heavy light-meson – Goldstone boson scattering phase shifts using the Luescher method on CLS 2+1 flavor gauge field ensembles. In a first iteration we will focus on D-meson – pion scattering in the elastic scattering region at various pion masses using ensembles with three lattice spacings. We employ ensembles on the CLS quark-mass trajectory with a fixed trace of the quark-mass matrix as well as ensembles with a strange-quark mass fixed close to its physical value, which will allow us to study both the light and the strange quark-mass dependence of positive parity heavy-light hadrons close to threshold. 

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4. Modeling Field Line Curvature Scattering Loss of 1–10 MeV Protons During Geomagnetic Storms

   https://doi.org/10.1029/2023JA032377  

   Lozinski, Alexander R; Horne, Richard B; Glauert, Sarah A; Kellerman, Adam C; Bortnik, Jacob; Claudpierre, Seth G; Manweiler, Jerry W; Spence, Harlan E (April 2024, Journal of Geophysical Research: Space Physics)

   Abstract The proton radiation belt contains high fluxes of adiabatically trapped protons varying in energy from ∼one to hundreds of megaelectron volts (MeV). At large radial distances, magnetospheric field lines become stretched on the nightside of Earth and exhibit a small radius of curvatureR_Cnear the equator. This leads protons to undergo field line curvature (FLC) scattering, whereby changes to the first adiabatic invariant accumulate as field strength becomes nonuniform across a gyroorbit. The outer boundary of the proton belt at a given energy corresponds to the range of magneticLshell over which this transition to nonadiabatic motion takes place, and is sensitive to the occurrence of geomagnetic storms. In this work, we first find expressions for nightside equatorialR_Cand field strengthB_eas functions of Dst andL* to fit the TS04 field model. We then apply the Tu et al. (2014,https://doi.org/10.1002/2014ja019864) condition for nonadiabatic onset to solve the outer boundaryL*, and refine our expression forR_Cto achieve agreement with Van Allen Probes observations of 1–50 MeV proton flux over the 2014–2018 era. Finally, we implement this nonadiabatic onset condition into the British Antarctic Survey proton belt model (BAS‐PRO) to solve the temporal evolution of proton fluxes atL ≤ 4. Compared with observations, BAS‐PRO reproduces storm losses due to FLC scattering, but there is a discrepancy in mid‐2017 that suggests a ∼5 MeV proton source not accounted for. Our work sheds light on outer zone proton belt variability at 1–10 MeV and demonstrates a useful tool for real‐time forecasting. 

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5. Alloy scattering of phonons

   https://doi.org/10.1039/C9MH01990A  

   Gurunathan, Ramya; Hanus, Riley; Snyder, G. Jeffrey (June 2020, Materials Horizons)

   Solid-solution alloy scattering of phonons is a demonstrated mechanism to reduce the lattice thermal conductivity. The analytical model of Klemens works well both as a predictive tool for engineering materials, particularly in the field of thermoelectrics, and as a benchmark for the rapidly advancing theory of thermal transport in complex and defective materials. This comment/review outlines the simple algorithm used to predict the thermal conductivity reduction due to alloy scattering, as to avoid common misinterpretations, which have led to a large overestimation of mass fluctuation scattering. The Klemens model for vacancy scattering predicts a nearly 10× larger scattering parameter than is typically assumed, yet this large effect has often gone undetected due to a cancellation of errors. The Klemens description is generalizable for use in ab initio calculations on complex materials with imperfections. The closeness of the analytic approximation to both experiment and theory reveals the simple phenomena that emerges from the complexity and unexplored opportunities to reduce thermal conductivity. 

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