Abstract
The -particles from have been investigated with a variable air pressure absorption cell, ionization chamber and linear amplifier. It has been established that there are two groups of -particles differing at 760 mm pressure and 15°C by 3.08±0.10 mm range reduced to zero bombarding voltage. The groups have been shown to be associated with the production of in the ground state and in an excited state. At 239 kv bombarding voltage, the excited state is formed 1.7 times as often as the ground state. The energy balance, , associated with the production of the ground state has been determined to be 7.093±0.022 Mev. The energy of the excited level has been determined to be 494±16 kev. The total yield curve for -particles has been investigated from 235 kv to 390 kv bombarding voltage. The measured value for the energy of the excited level in is discussed in connection with values from other reactions in which is an end product and with -ray measurements of the level.
- Received 4 March 1940
DOI:https://doi.org/10.1103/PhysRev.57.855
©1940 American Physical Society