nLab
proton

Contents

Context

Physics

physics, mathematical physics, philosophy of physics

Surveys, textbooks and lecture notes


theory (physics), model (physics)

experiment, measurement, computable physics

Fields and quanta

Contents

Idea

A proton is a certain bound state of three quarks, hence a baryon.

The bound states of protons and neutrons (jointly: nucleons) in turn are nuclei, the cores of atoms. The proton alone is the nucleus of the hydrogen atom.

In the standard model of particle physics the proton is stable, and experiment highly constrains possible rare proton decay (see there). But some models beyond the standard model (notably many, but not all, GUT models) do imply rare proton decay.

Properties

Mass

A proton has rest mass about a GeV:

m proton0.938GeV. m_{proton} \simeq 0.938 GeV \,.

Spin

The contribution of the constituents (quarks, gluons) to the total spin of the proton turns out to be subtle (“proton spin crisis”) Thomas 08.

References

See also

On the spin of the proton (proton spin crisis):

  • Anthony Thomas, The spin of the proton, Progress in Particle and Nuclear Physics Volume 61, Issue 1, July 2008, Pages 219–228 Quarks in Hadrons and Nuclei — 29th Course International Workshop on Nuclear Physics (arXiv:0805.4437)

  • Anthony Thomas, The resolution of the proton spin crisis, 2008 (pdf)

Last revised on January 17, 2020 at 23:35:20. See the history of this page for a list of all contributions to it.