Revisiting lifetimes of doubly charmed baryons

Abstract

Abstract We present updated predictions for lifetimes of doubly charmed baryons, within the heavy quark expansion, including available NLO α s contributions and newly-computed terms in the 1/m c series. Our improved results confirm the expected hierarchy τ Ξ cc + < τ Ω cc + < τ Ξ cc + + , $$ \tau \left({\Xi}_{cc}^{+}\right)<\tau \left({\Omega}_{cc}^{+}\right)<\tau \left({\Xi}_{cc}^{++}\right), $$ while the predicted lifetime τ Ξ cc + + $$ \tau \left({\Xi}_{cc}^{++}\right) $$ = 0.32 ± 0.5 − 0.7 + 0.8 $$ {0.5}_{-0.7}^{+0.8} $$ ps is consistent with the recent LHCb determination. We provide predictions for the lifetime ratios of the Ξ cc + $$ {\Xi}_{cc}^{+} $$ and Ω cc + $$ {\Omega}_{cc}^{+} $$ baryons relative to the Ξ cc + + $$ {\Xi}_{cc}^{++} $$ baryon, namely τ Ξ cc + / τ Ξ cc + + $$ \tau \left({\Xi}_{cc}^{+}\right)/\tau \left({\Xi}_{cc}^{++}\right) $$ = 0.22 ± 0.05 ± 0.04 and τ Ω cc + / τ Ξ cc + + $$ \tau \left({\Omega}_{cc}^{+}\right)/\tau \left({\Xi}_{cc}^{++}\right) $$ = 0.52 ± 0.13 − 0.02 + 0.03 $$ {0.13}_{-0.02}^{+0.03} $$ .

Keywords

• Charm Flavour Violation
• Properties of Hadrons