Question

The masses of 11C and 11B are respectively 11.0114 u and 11.0093 u. Find the maximum energy a positron can have in the β*-decay of 11C to 11B.

Answer 1

Explanation:

It is given:

11C has the mass, m(11C) = 11.0114 u

11B has the mass, m(11B) = 11.0093 u

In the decay of β+ decay (Q), the liberated energy is shown as

$\mathrm{Q}=-\mathrm{m} \mathrm{B} 11+\mathrm{mC} 11-2 \mathrm{mec} 2$

$=0.0010028 \times 931 \mathrm{MeV}$

Q = 933.6 keV

The neutrino’s energy for the positron’s maximum KE can be considered as zero.

Therefore, the positron’s maximum KE = 933.6 keV