Energy and Half-Life of theBe10Radioactivity

The half-life and upper limit beta-ray energy of ${\mathrm{Be}}^{10}$ have been measured, using a sample prepared from a strongly deuteron-bombarded Be target. The upper limit energy, from the inspection end point of the absorption curve, is 560±10 kev. The half-life, from the specific activity (46 disintegrations per sec. per mg Be) and the directly measured isotopic abundance (one part in 18,600) is (2.5±0.5)×${10}^6$ years. A rough excitation curve and good evidence for the absence of a gamma-ray were also obtained.