particle shower
cascade of secondary particles produced as the result of a high-energy particle interacting with dense matter
en-GB/ˈpɑːtɪkəl ˈʃaʊə/
en-US/ˈpɑɹtɪkəl ˈʃaʊɚ/
cascade of secondary particles produced as the result of a high-energy particle interacting with dense matter