  The investigation of the energy frontier in physics requires novel concepts
for future colliders. The idea of a muon collider is very appealing since it
would allow to study particle collisions at up to tens of TeV energy, while
offering a cleaner experimental environment with respect to hadronic colliders.
One key element in the muon collider design is the low-emittance muon
production. Recently,the Low EMittance Muon Accelerator (LEMMA) collaboration
has explored the muon pair production close to its kinematic threshold by
annihilating 45 GeV positrons with electrons in a low Z material target. In
this configuration, muons are emerging from the target with a naturally
low-emittance. In this paper we describe the performance of a system, to study
this production mechanism, that consists in several segmented absorbers with
alternating active layers composed of fast Cherenkov detectors together with a
muon identification technique based on this detector. Passive layers were made
of tungsten. We collected data corresponding to muon and electron beams
produced at the H2 line in the North Area of the European Organization for
Nuclear Research (CERN) in September 2018.
