Z° Isospin: Understanding T³=0 and Weak Isospin in Particle Physics

[tom.stoer]

Z° and weak isopsin

The Z° is a mixture of the B (iso-scalar) and the W° (iso-triplet with T³=0). Is it OK to say that the Z° still has T³=0? Or is this meaningless due to the breaking of the original SU_wI(2) * U_Y(1) to U_em(1) and the mixing in the Z°?

 

[phyzguy]

Since both the iso-scalar and the T3=0 component of the iso-triplet have T3=0, after mixing the resulting states (Z0 and photon) should still have T3=0 (I think).

 

[tom.stoer]

I think so, too, but is this really correct?

 

[Vanadium 50]

The Z is in an eigenstate of Q, and in an eigenstate of Y, right? So it must be in an eigenstate of T3.

 

[tom.stoer]

right