The neutrinos passes undetected also through the muon detectors, since they only interact weakly with the weak interaction. Therefore, a neutrino will interact very seldom with its surroundings.
Neutrinos are the only particles that normally cannot be detected in a particle detector. Despite this, it is still possible to indirectly deduce if neutrinos were created in a particle collision. In collisions with neutrinos, less energy and momentum will be detected than expected from the centre-of-mass energy.