Wed·Dec 22, 2021Wednesday·December 22, 2021

1. 01*

   Towards a discovery of BSM physics from the Cabibbo angle anomaly

   Chien-Yeah Seng🇩🇪

   New developments in both the theories and experiments related to the extraction of the top-row Cabibbo-Kobayashi-Maskawa matrix elements $V_{ud}$ and $V_{us}$ led to a series of new anomalies, for instance the apparent violation of the top-row unitarity relation. It is important to further reduce all the associated Standard Model theory uncertainties in order to better understand whether such observations point towards the possibility of physics beyond the Standard Model, or rather some unexpectedly large Standard Model effects. This requires improved studies of tree-level and higher-order Standard Model corrections that enter the beta decays of pions, neutron, nuclei and kaons. We will briefly review the recent progress along this direction and discuss possible improvements in the future.

   ↳ hep-phhep-exhep-latnucl-ex+1Mod.Phys.Lett.A(2022)·7 citations
2. 02*

   A study of the elastic $\pi N$ scattering at finite baryon density

   Hyeon-dong Han🇰🇷 · Parada T. P. Hutauruk🇰🇷 · Seung-il Nam🇰🇷

   We investigate the elastic $\pi N$ scattering for the $I=3/2$ channel dominated by the $\Delta (1232)$ resonance at finite baryon density ${\rho }_B$ for the symmetric nuclear matter, employing the effective Lagrangian approach at the tree-level Born approximation. The quark-meson coupling (QMC) model and linear-density approximation are employed to describe the medium modifications for the in-medium baryon properties, such as the nucleon and $\Delta$ masses, and $\Delta$ full decay width. We first reproduce the experimental data in vacuum by fitting the model parameters, then analyze various physical observables including total and differential cross sections, proton-spin asymmetry in medium. It turns out that the $\Delta$-resonance contribution becomes diminished with respect to ${\rho }_B$, due to the weaker $\pi N$-interaction strength in medium. Beyond the $\Delta$-resonance region $\sqrt{s}\gtrsim 1.5$ GeV, the cross sections are almost independent of the density. The present results will be useful to understand the role of the $\Delta$ resonance in the neutron-star equation of state (EoS) as well as in relativistic heavy-ion collision experiments.

   ↳ nucl-thhep-phnucl-exMod.Phys.Lett.A(2022)·3 citations
3. 03*

   Nu Tools: Exploring Practical Roles for Neutrinos in Nuclear Energy and Security

   Oluwatomi Akindele🇺🇸 · Nathaniel Bowden🇺🇸 · Rachel Carr🇺🇸 · Andrew Conant🇺🇸 · Milind Diwan🇺🇸 · Anna Erickson🇺🇸 · Michael Foxe🇺🇸 · Bethany L. Goldblum🇺🇸 · Patrick Huber🇺🇸 · Igor Jovanovic🇺🇸 · Jonathan Link🇺🇸 · Bryce Littlejohn🇺🇸 · Pieter Mumm · Jason Newby🇺🇸

   For decades, physicists have used neutrinos from nuclear reactors to advance basic science. These pursuits have inspired many ideas for application of neutrino detectors in nuclear energy and security. While developments in neutrino detectors are now making some of these ideas technically feasible, their value in the context of real needs and constraints has been unclear. This report seeks to help focus the picture of where neutrino technology may find practical roles in nuclear energy and security. This report is the final product of the Nu Tools study, commissioned in 2019 by the DOE National Nuclear Security Administration (NNSA) Office of Defense Nuclear Nonproliferation Research and Development (DNN R&D). The study was conducted over two years by a group of neutrino physicists and nuclear engineers. A central theme of the study and this report is that useful application of neutrinos will depend not only on advancing physics and technology but also on understanding the needs and constraints of potential end-users. The Study Approach emphasized broad end-user engagement. The major effort, undertaken from May to December 2020, was a series of engagements with the wider nuclear energy and security communities. Interviews with 41 experts revealed points of common understanding, which this report captures in three Cross-Cutting Findings, a Framework for Evaluating Utility, and seven Use Case Findings. The report concludes with two Recommendations. The findings and recommendations are summarized below. The respective ordering within each category does not represent a prioritization or implied value judgement.

   ↳ hep-phhep-exnucl-ex21 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.