Analysis of the kinematic boundaries of the quasielastic neutrino-nucleus cross section in the superscaling model with a relativistic effective mass

This work has been partially supported by the former Spanish Ministerio de Economia y Competitividad and ERDF (European Regional Development Fund) under Contract No. FIS2017-85053-C2-1P, by the Junta de Andalucía Grant No. FQM225, by Contract No. PID2020– 114767 GB-I00 funded by MCIN/ AEI /10.13039/ 501100011033, and by the Russian Science Foundation Grant No. 18-12-00271.In this work we obtain the analytical expressions for the boundaries of the charged current quasielastic (CCQE) double differential cross section in terms of dimensionless energy and momentum transfers, for the Relativistic Fermi Gas (RFG) and the Superscaling approach with relativistic effective mass (SuSAM∗) models, within the scaling formalism. In addition, we show that this double differential cross section in the scaling formalism has very good properties to be implemented in the Monte Carlo (MC) neutrino event generators, particularly because its peak is almost flat with the (anti)neutrino energy. This makes it especially well suited for the event generation by the acceptance-rejection method usually used in the neutrino generators. Finally, we analyze the total CCQE cross section σ(Eν) for both models and attribute the enhancement observed in the SuSAM∗ total cross section to the high-momentum components which are present, in a phenomenological way, in its scaling function, while these are absent in the RFG model.Spanish Ministerio de Economia y CompetitividadEuropean Regional Development FundJunta de AndalucíaRussian Science Foundatio

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