PROTON

BACK

A proton is a subatomic particle, symbol p or p⁺ , with a positive electric charge of +1e elementary charge and a mass slightly less than that of a neutron. Protons and neutrons, each with masses of approximately one atomic mass unit, are collectively referred to as "nucleons".

CHARGE

RADIUS

0.8414(19) fm

MASS

1.67262192369(51)×10−27

kg;938.27208816(29)MeV/c2; 1.007276466621(53) u

ELECTRIC CHARGE

+1 e; 1.602176634×10−19 C

SYMBOL

p, p+, N+, 1; 1H+

COMPOSITION

2 up quarks (u), 1 down quark (d)

ELECTRIC DIPOLE MOMENT

< 5.4×10−24 e⋅cm

ELECTRIC POLARIZABILITY

1.20(6)×10−3 fm3