New detector for studies of cumulative processes in hadron collisions in NA61(SHINE) at the CERN SPS

The increase of luminosity of the SPS beams expected after 2020 allows considering the investigation of rather rare processes. In particular, so-called cumulative particle production can be studied in hadron collisions by measurements of secondary particle yields in regions kinematically forbidden for reactions with free nucleons. Such processes could be either a result of hard parton collisions with some large-density multi-quark configuration or of the formation of heavy baryonic resonances. Measurements in the backward hemisphere in fixed target experiment should provide the event-by-event data that could be used, along with those from the forward region, for a correlation analysis, thus resulting in new constraints on models. In this report the preliminary design, ideas, technology and the first GEANT simulations of a proposed new detector are presented and discussed.