Question

who discovered proton,neutron,electron and meson???

Answer 1

Electron was discovered by J. J. Thomson in 1897 

In 1909, Rutherford discovered proton in his famous gold foil experiment

In 1932, James Chadwick discovered was neutrons.

meson was discovered in 1936 by Carl David Anderson.

Answer 2

I think Ernest Rutherford discovered neutron and proton
electron was discovered by J.J .Thomson
meson was discovered by Yukawa Hideki