First observation of Λ c (2595) + → Λ c + π 0 π 0 and Λ c (2625) + → Λ c + π 0 π 0

Journal article

By analysing e+e− annihilation data corresponding to an integrated luminosity of 368.48 pb−1 collected at the centre-of-mass energies of s = 4.918 and 4.951 GeV with the BESIII detector, we report the first observation of Λc(2595)+ and Λc(2625)+ → Λc+π0π0 with statistical significances of 7.9σ and 11.8σ, respectively. The branching fractions of Λc(2595)+ and Λc(2625)+ → Λc+π0π0 are measured to be (59.5 ± 11.1stat. ± 7.9syst.)% and (41.0 ± 5.2stat. ± 3.3syst.)%, respectively. The absolute branching fraction of Λc(2595)+ is consistent with the expectation of the mechanism referred to as the threshold effect, proposed for the strong decays of Λc(2595)+ within uncertainty.

Authors: Ablikim, M; Achasov, MN; Adlarson, P; Afedulidis, O; Ai, XC

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Springer
• Journal: Journal of High Energy Physics
• Volume: 2025
• Issue: 8
• Article number: 65
• Publication date: 2025-08-08
• Acceptance date: 2025-07-14
• DOI: 10.1007/jhep08(2025)065
• EISSN: 1029-8479
• ISSN: 1126-6708
• Language: English
• Keywords: e+-e− Experiments; Charm Physics; Branching fraction