Mass Spectrograph Analysis of Bromine

An attempt has been made to observe a third isotope of bromine to explain the three periods of the artificial radioactivity induced by slow neutrons. Neither of the expected isotopes is present to more than 1 part in 3000. The relative abundance of the known isotopes was measured. The processes of formation of positive and negative ions of bromine by slow electrons were studied and values were deduced for the heat of dissociation of ${\mathrm{Br}}_2$ and for the electron affinity of Br.