The two selected rates are T4 singles and a coincidence between T6 and
T7. For the nominal thresholds in Table II and for particles incident through
the telescope aperture, T4 responds to 10 to 30 MeV protons, while
T6.T7 responds to 30 to 80 MeV. There will, of course, be a significant
background due to higher energy cosmic rays that pass through the sides of
the SIS box, but the minimum required energy is considerably higher in this