How Does a Down Quark Transform Into an Up Quark During Beta Decay?

[ythaaa]

for beta decay
n --> p + e- + antineutrino

since neutron has quarks udd while proton has uud, only the d changes to u. is it correct to guess that it is the down quark inside the neutron which "transform" into up quark?

ie d --> u + e- + antineutrino

 

[AlphaNumeric]

Yes, though there is an intermediate state, in that the process is actually :

[tex]d \to u + W^{-} \to u + e^{-} + \bar{\nu}_{e}[/tex]

The intermediate step was not known about when the weak force was first being modeled because it only exists for a tiny amount of time because the W boson is so massive and unstable.

 

[sir-pinski]

Yes, you are correct. In beta decay, a neutron (udd) transforms into a proton (uud) by changing one of its down quarks into an up quark. This process is mediated by the weak force, which also produces an electron and an antineutrino. This transformation of quarks is known as a quark transition and is a fundamental process in the Standard Model of particle physics.