Question

Which of the following process processes are forbidden by the law of conservation of strangeness :
(1)`pi^(-)+prarr Sigma^(-)+K^(+)`,
(2) `pi^(-)+prarrSigma^(+)+K^(-)`,
(3)`pi^(-)+prarrK^(+)+K^(-)+n`,
(4) `n+prarr ^^ ^(0)+Sigma^(+)`,
(5) `pi^(-)+nrarr Xi^(-)+K^(+)+K^(-)`,
(6) `K^(-)+prarr Omega+K^(+)+K^(0)` ?

Answer 1

(1) `pi^(-)+prarrSigma^(-)+K^(+)`
`0 0 -1 1`
so `DeltaS=0` allowd.
(2) `pi^(-)+prarrSigma^(+)+K^(-)`
`0 0 -1 1`
so `DeltaS= -2` forbiddeb
(3) `pi^(-)+prarrK^(-)+K^(+)+n`
`0 0 rarr-1 1 0`
so `DeltaS=0`, allowed
(4)`n+prarr^^ ^(0)+Sigma^(+)`
`0 0 -1 -1`
so `DeltaS= -2`. forbidden
(5) `pi^(-)+nrarr=^(-)+K^(+)+K^(-)`
`0 0rarr -2 1 -1`
so `DeltaS= -2`. forbidden.
(6) `K^(-)+prarrSigma^(-)+K^(+)K^(o)`
`-1 0 3+1+1`
so `DeltaS=0` allowed.