How is the difference in ground and excited state of baryons masses explained within QCD and SM?

Question

How is the difference in ground and excited state of baryons masses ($Sigma$ and $Sigma^*$, $Xi$ and $Xi^*$ for example) explained within QCD and SM? Is it possible to calculate (predict) this mass difference for each individual case? Is it possible to predict the particles masses with respect to the Higgs field (Higgs boson mass)?

Cosmas Zachos · Accepted Answer

Higgs couplings will only determine the current quark masses of your system, a small correction to your spectroscopy, unless your Baryons have a heavy quark subscript like c or b, in which case, again, the Higgs has done its job, and all that is left is the nonperturbative strong interactions at work.
The specific baryon mass differences you are referring to are due to hyperfine interactions in QCD, which can be accommodated as in Section IV.B.3 of

Klempt, Eberhard, and Jean-Marc Richard (2010): "Baryon spectroscopy." Reviews of Modern Physics  82 no. 2  , p. 1095,

see the chromomagnetic spin-spin term of eqn (30).

How is the difference in ground and excited state of baryons masses explained within QCD and SM?

One Answer

Add your own answers!

Ask a Question