Further evidence for heavy particles in the cosmic radiation

In a continuation of a study of slow, penetrating cosmic-ray particles at sea level further evidence has been obtained for long-lived particles with mass $\approx \left(\frac{9}{2}\right)m_p$ and charge either exactly or approximately equal to unity. Also, in relatively complicated events, further possible examples of slow, accompanied, heavy particles with charge ≈ 0.7 were observed.