I read about a technique called b-tagging in which one can check if a b meson was produced in a collision by looking for a jet which has a secondary vertex within it. The reason is that b mesons are long lived, so that meson would travel a bit before decaying, hence the secondary vertex. Why are b meson long lived? And why can't we do this with other kind of quarks, like strange or charm? Thank you!

• Is your question about b-tagging, or a very different one: why are the lifetimes of K/D/B mesons, in seconds, $10^{-8}~/ ~ 10^{-14}~/ ~ 10^{-12}$, respectively? – Cosmas Zachos Oct 22 at 20:23