We have measured lifetimes of Λ hypernuclei over a broad mass range explicitly identifying Λ hypernuclear production in the \(π+, K+\) reaction. The obtained results are τ\(12ΛC\) = 231+/-15 ps, τ\(28ΛSi\) = 206+/-12 ps, and τ\(ΛFe\) = 215+/-14 ps. The lifetimes of Λ hypernuclei over the mass region from carbon to iron are found almost constant at about 80% of that of free Λ within the statistical uncertainties. The short-range nature of the nonmesonic weak decay process, which is dominant in heavy Λ hypernuclei, is possibly responsible for the observed weak hypernuclear mass dependence.
ASJC Scopus subject areas
- Physics and Astronomy(all)