InterviewSolution
Saved Bookmarks
| 1. |
Indicate the reasons why the following processes are forbidden: (1) `Sigma^(-)rarr^^ ^(0)+pi^(-)`, (2) `pi^(-)+prarrK^(+)+K^(-)`, `K^(-)+n rarr Omega^(-)+K^(+)+K^(0)`, (6) `murarr e^(-)+v_(e )+v_(mu)`. |
|
Answer» (1)` Sigma^(-)Sigma^(-)rarr^^ ^(0)+pi^(-)`, (2) `pi^(-)+prarr K^(+)+K^(-)`, `K^(-)+n rarr Omega^(-)+K^(+)+K^(0)`, (6) `murarr e^(-)+v_(e )+v_(mu)`. is forbidden by energy conservation. The mass difference `M_(Sigma)-M_(^^ ^(0))= 82(MeV)/(c^(2)) lt m_(pi)^(-)` ( The process `1rarr 2+3` will be allowed only if `m_(1)gt m_(2)+m_(3)`.) (2) `pi^(-)+prarrK^(+)K^(-)` is disallowed by conservation of baryon number. (3) `K^(-)+n rarr Omega^(-)+K^(+)+K^(0)` is forbidden by conservation of charge (4) `n+prarr Sigma^(+)^^ ^(0)` is forbidden by strangerness conservation. (5) `pi^(-)rarrmu^(-)+e^(-)+e^(+)` is forbidden by conservation of muon number (or lepton number). (6) `mu^(-)rarre^(-)+v_(e )+ overset(~)v_(mu)` is forbidden by the seperate conservation of muon number as well as lepton number. |
|