2
$\begingroup$

Why can the hyperon $\Omega^{-}$ not decay by strong interaction? It seems that strangeness must be violated, but why is it the only way?

$\endgroup$
2
  • $\begingroup$ As an answer to the second question, strangeness tends not to be conserved in weak interaction or decay. $\endgroup$
    – Meow
    Commented Oct 29, 2012 at 12:19
  • 2
    $\begingroup$ Are you looking for something beyond "Because the strong interaction respects flavor."? If so, can you be more specific? $\endgroup$ Commented Oct 29, 2012 at 13:01

1 Answer 1

3
$\begingroup$

The reason is because it is the lightest baryon with strangeness 3, the mass energy of lightest strange object of s=1 (the kaons) is greater than 1/3 it's mass, so it can't decay into these.

It is a general principle of energy conservation and strangeness conservation: the lightest example of any conserved quantum numbers can't decay without changing this number. In this case you need the strangeness to go down, and this requires weak decay, because, as dmckee says in his comment, the strong interaction respects flavor.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.