Nuclear Theory·nucl-th

Friday·November 5, 2021

7 papers—4 primary·3 cross-listed

05
Patterns of $C$ - and $C P$ -violation in hadronic $η$ and $η^{'}$ three-body decays
Hakan Akdag🇩🇪 · Tobias Isken🇩🇪 · Bastian Kubis🇩🇪
We construct hadronic amplitudes for the three-body decays $η^{(')} \to π^{+} π^{-} π^{0}$ and $η^{'} \to η π^{+} π^{-}$ in a non-perturbative fashion, allowing for $C$ - and $C P$ -violating asymmetries in the $π^{+} π^{-}$ distributions. These amplitudes are consistent with the constraints of analyticity and unitarity. We find that the currently most accurate Dalitz-plot distributions taken by the KLOE-2 and BESIII collaborations confine the patterns of these asymmetries to a relative per mille level. Our dispersive representation allows us to extract the individual coupling strengths of the $C$ - and $C P$ -violating contributions arising from effective isoscalar and isotensor operators in $η^{(')} \to π^{+} π^{-} π^{0}$ and an effective isovector operator in $η^{'} \to η π^{+} π^{-}$ , while the strongly different sensitivities to these operators can be understood from chiral power counting arguments.
↳ hep-phhep-exnucl-thJHEP(2022)·27 citations
06
Neutrino Interactions with Matter and the MiniBooNE anomaly
Luis Alvarez-Ruso🇪🇸 · Eduardo Saul-Sala🇪🇸
The excess of electron-like events measured by MiniBooNE challenges our understanding of neutrinos and their interactions. We review the status of this open problem and ongoing efforts to resolve it. After introducing the experiment and its results, we consider the main experimental backgrounds and the related physics of neutrino interactions with matter such as quasielastic-like scattering and weak pion production on nucleons and nuclei. Special attention is paid to single photon emission in neutral current interactions and, in particular, its coherent channel. The difficulties to reconcile the MiniBooNE anomaly with global oscillation analysis is then highlighted. We finally outline some of the proposed solutions of the puzzle involving unconventional neutrino-interaction mechanisms.
↳ hep-phhep-exnucl-thEur.Phys.J.ST(2021)·27 citations
07
Nuclear two point correlation functions on a quantum-computer
Alessandro Baroni🇺🇸 · Joseph Carlson🇺🇸 · Rajan Gupta🇺🇸 · Andy C. Y. Li🇺🇸 · Gabriel N. Perdue🇺🇸 · Alessandro Roggero🇮🇹
The calculation of dynamic response functions is expected to be an early application benefiting from rapidly developing quantum hardware resources. The ability to calculate real-time quantities of strongly-correlated quantum systems is one of the most exciting applications that can easily reach beyond the capabilities of traditional classical hardware. Response functions of fermionic systems at moderate momenta and energies corresponding roughly to the Fermi energy of the system are a potential early application because the relevant operators are nearly local and the energies can be resolved in moderately short real time, reducing the spatial resolution and gate depth required. This is particularly the case in quasielastic electron and neutrino scattering from nuclei, a topic of great interest in the nuclear and particle physics communities and directly related to experiments designed to probe neutrino properties. In this work we use current quantum hardware and error mitigation protocols to calculate response functions for a highly simplified nuclear model through calculations of a 2-point real time correlation function for a modified Fermi-Hubbard model in two dimensions with three distinguishable nucleons on four lattice sites.
↳ quant-phhep-latnucl-thPRD(2022)·41 citations

Affiliations

first authorsco-authorsvia INSPIRE

Patterns of C- and CP-violation in hadronic η and η′ three-body decays

Neutrino Interactions with Matter and the MiniBooNE anomaly

Nuclear two point correlation functions on a quantum-computer

Affiliations

Patterns of $C$ - and $C P$ -violation in hadronic $η$ and $η^{'}$ three-body decays