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arXiv · 1901.10192

Weak production of strange and charm ground-state baryons in nuclei

J. E. Sobczyk·N. Rocco·A. Lovato·J. Nieves
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Abstract

We present results for the quasi-elastic weak production of $Λ$ and $Σ$ hyperons induced by $\barν$ scattering off nuclei, in the kinematical region of interest for accelerator neutrino experiments. We employ realistic hole spectral functions and we describe the propagation of the hyperons in the nuclear medium by means of a Monte Carlo cascade. The latter strongly modifies the kinematics and the relative production rates of the hyperons, leading to a non-vanishing $Σ^+$ cross section, to a sizable enhancement of the $Λ$ production and to a drastic reduction of the $Σ^0$ and $Σ^-$ distributions. We also compute the quasi-elastic weak $Λ_c$ production cross section, paying special attention to estimate the uncertainties induced by the model dependence of the vacuum $n\to Λ_c$ weak matrix element. In this regard, the recent BESIII measurements of the branching ratios of $Λ_c\rightarrow Λl^+ν_l$ ($l=e,μ$) are used to benchmark the available theoretical predictions.

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J. E. Sobczyk, N. Rocco, A. Lovato, J. Nieves. 2019-01-29. Weak production of strange and charm ground-state baryons in nuclei. https://doi.org/10.1103/physrevc.99.065503

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