A Short-lived Metastable State in Titanium-46

Abstract

Benedetti and McGowan¹, Mandeville and Scherb² and Hirzel, Stoll and Wäffler³ have attempted to detect short-lived metastable states of radioactive nuclei by using the method of delayed β-β and β-γ coincidences. Several decay periods have been detected by these methods. We have examined delayed γ-γ coincidences using a method similar to that used by Bunyan et al.⁴, but with two counting channels instead of one. The delay of one of the channels is kept fixed and is called the fixed channel. The γ-counters were kept symmetrically with respect to the source and had sufficient thickness of matter to cut down all β-rays below 1·7 MeV. The γ-counters, 3 cm. long and 2 cm. in diameter, were filled with a standard argon and petroleum ether mixture at a pressure of 14 cm. of mercury. The counters had a plateau of 200 volts and the starting potential was 850 volts. Delayed γ-γ coincidences were observed with a source of scandium oxide irradiated with neutrons arranged as in Fig. 1 with respect to the two γ-counters.