Implementation of the Martini-Ericson-Chanfray-Marteau RPA-based neutrino and antineutrino cross-section model in the GENIE neutrino event generator

We discuss the first implementation of the Martini-Ericson-Chanfray-Marteau random phase approximation-based (anti)neutrino cross-section model for quasielastic (1p1h) and multinucleon (2p2h and 3p3h) excitations in the widely used GENIE neutrino event generator. Validation steps are presented, in particular, through direct comparisons of GENIE cross-section output with original calculations performed by the authors of the model. Predictions for <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:mrow> <a:mmultiscripts> <a:mrow> <a:mi mathvariant="normal">C</a:mi> </a:mrow> <a:mprescripts/> <a:none/> <a:mrow> <a:mn>12</a:mn> </a:mrow> </a:mmultiscripts> </a:mrow> </a:math> , <d:math xmlns:d="http://www.w3.org/1998/Math/MathML" display="inline"> <d:mrow> <d:mmultiscripts> <d:mrow> <d:mi mathvariant="normal">O</d:mi> </d:mrow> <d:mprescripts/> <d:none/> <d:mrow> <d:mn>16</d:mn> </d:mrow> </d:mmultiscripts> </d:mrow> </d:math> , and <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"> <g:mrow> <g:mmultiscripts> <g:mrow> <g:mi>Ar</g:mi> </g:mrow> <g:mprescripts/> <g:none/> <g:mrow> <g:mn>40</g:mn> </g:mrow> </g:mmultiscripts> </g:mrow> </g:math> are compared with some available T2K and MicroBooNE experimental measurements showing a reasonable agreement.