4 ms·
Charm, Up and Top are all different. They share some properties but not all and therefore annihilation can not take place.
by ganzuul 5y ago
Charm, Up and Top are all different. They share some properties but not all and therefore annihilation can not take place.
- dukwon 5y agoSure it can, but it has to proceed via the weak interaction, and it's suppressed by the GIM mechanism. For example, D⁰→γγ (c̅u or cu̅ annihilation) is rare and not yet observed, but it's allowed.
- deleted 5y ago[deleted]