The nuclear magneton (symbol μ_p), is a physical constant of magnetic moment, defined by: In science, a physical constant is a physical quantity whose numerical value does not change. ... In physics, the magnetic moment of an object is a vector relating the aligning torque in a magnetic field experienced by the object to the field vector itself. ...

where:

e is the elementary charge,

is the reduced Planck's constant,

m_p is the proton rest mass

In the SI system of units its value is approximately: The elementary charge (symbol e or sometimes q) is the electric charge carried by a single proton, or equivalently, the negative of the electric charge carried by a single electron. ... Plancks constant, denoted h, is a physical constant that is used to describe the sizes of quanta. ... Properties In physics, the proton (Greek proton = first) is a subatomic particle with an electric charge of one positive fundamental unit (1. ... The term mass in special relativity is used in a couple of different ways, occasionally leading to a great deal of confusion. ... The International System of Units (abbreviated SI from the French phrase, Système International dUnités) is the most widely used system of units. ... In physics and metrology, units are standards for measurement of physical quantities that need clear definitions to be useful. ...

μ_p = 5.050 786 6(17) × 10^-27 J·T^-1

See also proton magnetic moment. The joule (symbol J, also called newton metre, or coulomb volt) is the SI unit of energy and work. ... The tesla (symbol T) is the SI derived unit of magnetic flux density (or magnetic inductivity). ...