According to the Rutherford's atomic model,the electrons inside the atom are

Particles used in the Rutherford's scattering experiment to deduce the structure of atoms:

In the Rutherford experiment,for a head-on collision of $\alpha$-particles with a gold nucleus,the impact parameter is:

The graph which depicts the results of the Rutherford gold foil experiment with $\alpha$-particles is:
$\theta$: Scattering angle
$Y$: Number of scattered $\alpha$-particles detected
(Plots are schematic and not to scale)

The Franck-Hertz experiment proves that

The $\alpha$-particle is the nucleus of an atom of