Fis ee i a a re ae ate Ah tecs at alias ee ae 195 grams/cm 49 ° 46 180 Fic. 162.—-Effect of air-land interface on slow (thermal) neutrons generated by cosmic-ray protons 206
Fis ee i a a re ae ate Ah tecs at alias ee ae 195 grams/cm 49 ° 46 180 Fic. 162.—-Effect of air-land interface on slow (thermal) neutrons generated by cosmic-ray protons 206