Quark-model calculation of charmed-baryon production by neutrinos

Abstract

We study the neutrino production of 25 low-lying charmed-baryon resonances in the four-flavor quark model. The mass difference of ordinary and charmed quarks is explicitly taken into account. The quark model is used to determine the spectrum of the charmed-baryon resonances and the $q^2=0\mathrm{}$ values of the weak-current transition matrix elements. These transition matrix elements are then continued to spacelike $q^2$ values by a generalized meson-dominance ansatz for a set of suitably chosen invariant form factors. We find that the production of the $L=0\mathrm{}$ states $C_0$, $C_1$, and $C_{}^{*}{}_1{}^{}$ is dominant, with the $C_0$ produced most copiously. For $L=1,2\mathrm{}$ the $J^P={\frac{3}{2}}^{-},{\frac{5}{2}}^{+}$ charm states are dominant. We discuss the sensitivity of our results to various input assumptions, e.g., the ratio of charm-quark mass to ordinary-quark mass. We give differential cross sections, total cross sections, and energy-integrated total cross sections using experimental neutrino fluxes. We conclude that the charmed-baryon production rate can be as large as 3-4% of the total neutrino cross section in a region extending from charm threshold to $E\simeq 10$ GeV.