Question

The yield of a nuclear reaction producing radionuclides may be described in two ways: either by the ratio w of the number of nuclear reactions to the number of bombarding particles or by the quantity k, the ratio of the activity of the formed radionuclide to the number of bombarding particles, Find: 

(a) the half-life of the formed radionuclide, assuming w and k to be known; 

(b) the yield w of the reaction Li⁷(p, n)Be⁷ if after irradiation of a lithium target by a beam of protons (over t = 2.0 hours and with beam current I = 10 μA) the activity of Bel became equal to A = 1.35.10⁸ dis/s and its half-life to T = 53 days.

Answer 1

(a) Assuming of course, that each reaction produces a radio nuclide of the same type, the decay constant α of the radionuclide is k/w . Hence 

(b) number of bombarding particles is: It/e

(e = charge on proton). Then the number of Be⁷ produced is 

If λ = decay constant of Be⁷