Abstract
The γ-γ and β-γ coincidences of 38Cl. 28Al and 24Na were investigated.
38Cl: The predictions from the Fermi plots were confirmed, the existence of the 2.8mev group of β-rays being definitely shown by the kink in the β-γ coincidence against absorber thickness curve.
Of the three groups of β-rays, whose energies are 4.99mev, 2.80 mev and 1.16mev, the 2.80mev group accompanies a γ quantum of 2.19mev and the 1.16mev group two sue_??_essive γ quanta of 2.19mev and 1.64mev, the latter being emitted at first.
28Al: The β-γ coincidence remains constant throughout the whole range of the β-rays. There is no γ-γ coincidence.
24Na: In this case also, β-γ coincidence remains constant throughout the whole range of the β-rays But appreciable γ-γ coincidence was observed showing that two quanta are successively emitted each β disint_??_gration.
The angular correlation of the successive quanta was investigated at 90° and 180° of the angle subtend by the two counters to a source. In the case of 24Na the rate of coincidence showed no change at respective angle, while in the case of 38Cl the value at 90° was definitely larger than the one at 180°
