# Question #03070

Oct 8, 2017

$n + {e}^{+} \to p + {\overline{v}}_{e}$

#### Explanation:

A neutron and positron interact in the following way

$n + {e}^{+} \to p + {\overline{v}}_{e}$

producing a proton and an anti-electron neutrino.

The proton conserves charge, as the neutron has $0$ charge, the positron is $- 1$ (negative because it is antimatter), the proton is $+ 1$ and the neutrino is $0$, like the positron, as is is an anti-neutrino, not simply a neutrino.

The neutrino is produced to conserve lepton number, as both proton and neutron have lepton numbers of $0$ and baryon numbers of $1$, hence baryon number is also conserved.

By thinking about all of these conserved quantities, you can deduce what must be produced on the right side of the equation.