Is Isospin Conserved in Particle Interactions?

[rshalloo]

Homework Statement

Hey I just want to clarify something. In particle physics, isospin is a flavor quantum number. Is it isospin or the z component of isospin which is conserved in particle interactions

Homework Equations

electron neutrino + proton -> electron pion+ + proton

The Attempt at a Solution

from what I can tell isospin is not conserved while the z component of isospin is?
(also I realize from a decay point of view this violates conservation of energy I just wanted an example to demonstrate my point)

Thanks

 

[susskind_leon]

Isospin is not conserved under weak interaction.