Measurements of the absolute branching fractions of the Λc+ hadronic decays

Based on 4.5 fb⁻¹ of e⁺e⁻ collision data collected at center-of-mass energies between 4599.53 MeV and 4698.82 MeV with the BESIII detector, the absolute branching fractions of twelve Λc+ hadronic decay modes are measured with a double-tag technique. A global least-square fit is implemented simultaneously among different decay modes at different energy points. This paper gives the most precise results on the branching fractions of different decay modes to date, with precision improved by a factor of 2 to 3. Among them, the branching fraction of Λc+→pK−π+ is determined to be (6.61 ± 0.11 ± 0.12)%, where the first uncertainty is statistical and the second is systematic. In addition, the e+e−→Λc+Λ¯c− Born cross sections and the effective form factors (|G_eff|) at different energy points have been determined with the highest precision to date.