Lifetimes of Doubly Charmed Baryons

Understand

The lifetimes of doubly charmed hadrons are analyzed within the framework of the heavy quark expansion (HQE).

• Lifetime differences arise from spectator effects such as $W$-exchange and Pauli interference.
• The $\Xi_{cc}^{++}$ baryon is longest-lived in the doubly charmed baryon system owing to the destructive Pauli interference absent in the $\Xi_{cc}^+$ and $\Omega_{cc}^+$.
• In the presence of dimension-7 contributions, its lifetime is reduced from $\sim5.2\times 10^{-13}s$ to $\sim3.0\times 10^{-13}s$.