A subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen

Neutron is electrically neutral...

But it posses a spin...

And when it moves it has a finite kinetic energy...

A neutron and a proton almost have the same mass.

A neutron and 1,840 electrons almost have the same mass.

A lamp or an X-ray tube cannot be used to "add neutrons" to other nuclei because lamps and X-ray tubes are not neutron sources.

Neutron activation is generally something we do in an operating nuclear reactor. In the core of the reactor, there is a high neutron flux. Many, many neutrons are being released in the fissions that are going on in the nuclear core. Materials that are to be activated are lowered through ports and brought down into the neutron flux. Activation occurs. Lamps or X-rays do not produce neutrons, and cannot be used in neutron activation activities. No neutrons means no neutron activation.

selenium