# Determining excitated state of an electron of an $\rm H$ atom

Suppose we have an electron of $\rm{H}$ atom( suppose it is at 4th shell). But it can't remain in the excited state for a long time. So it can jump to 1st ,2nd or the 3rd orbital. What is the factor that decides whether the electron will jump to any one of the lower energy state orbitals. Or is that random?

The most usual one is the electric dipole approximation, which is clearly dominant. The probability is proportional to $\langle \phi_{final} | \vec{r} | \phi_{initial} \rangle$