First measurements of the absolute branching fraction of Λ_c(2625)^+→Λ^+_cπ^+π^- and upper limit on Λ_c(2595)^+→Λ^+_cπ^+π^-
arxiv(2024)
Abstract
The absolute branching fraction of the decay Λ_c(2625)^+→Λ^+_cπ^+π^- is measured for the first time to be (50.7 ±
5.0_stat.± 4.9_syst. )% with 368.48 pb^-1 of e^+e^-
collision data collected by the BESIII detector at the center-of-mass energies
of √(s) = 4.918 and 4.950 GeV. This result is lower than the naive
prediction of 67%, obtained from isospin symmetry, by more than 2σ,
thereby indicating that the novel mechanism referred to as the
threshold effect, proposed for the strong decays of
Λ_c(2595)^+, also applies to Λ_c(2625)^+. This
measurement is necessary to obtain the coupling constants for the transitions
between s-wave and p-wave charmed baryons in heavy hadron chiral
perturbation theory. In addition, we search for the decay
Λ_c(2595)^+→Λ^+_cπ^+π^-. No significant signal is
observed, and the upper limit on its branching fraction is determined to be
80.8% at the 90% confidence level.
MoreTranslated text
AI Read Science
Must-Reading Tree
Example
Generate MRT to find the research sequence of this paper
Chat Paper
Summary is being generated by the instructions you defined