TY - JOUR
T1 - Measurement of the branching fraction of the singly Cabibbo-suppressed decay Λc+ → Λk+
AU - BESIII Collaboration
AU - Ablikim, M.
AU - Achasov, M.N.
AU - Adlarson, P.
AU - Adlarson, P.
AU - Albrecht, M.
AU - Aliberti, R.
AU - Kalantar-Nayestanaki, Nasser
AU - Rodin, Viktor
N1 - Funding Information:
The BESIII collaboration thanks the staff of BEPCII and the IHEP computing center for their strong support. This work is supported in part by National Key R&D Program of China under Contracts No. 2020YFA0406400 and No. 2020YFA0406300; National Natural Science Foundation of China (NSFC) under Contracts No. 11635010, No. 11735014, No. 11835012, No. 11935015, No. 11935016, No. 11935018, No. 11961141012, No. 12022510, No. 12025502, No. 12035009, No. 12035013, No. 12192260, No. 12192261, No. 12192262, No. 12192263, No. 12192264, and No. 12192265; the Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program; Joint Large-Scale Scientific Facility Funds of the NSFC and CAS under Contract No. U1832207; 100 Talents Program of CAS; Project No. ZR2022JQ02 supported by Shandong Provincial Natural Science Foundation; The Institute of Nuclear and Particle Physics (INPAC) and Shanghai Key Laboratory for Particle Physics and Cosmology; ERC under Contract No. 758462; European Union’s Horizon 2020 research and innovation program under Marie Sklodowska-Curie Grant Agreement under Contract No. 894790; German Research Foundation DFG under Contracts No. 443159800, Collaborative Research Center CRC 1044, GRK 2149; Istituto Nazionale di Fisica Nucleare, Italy; Ministry of Development of Turkey under Contract No. DPT2006K-120470; National Science and Technology fund; National Science Research and Innovation Fund (NSRF) via the Program Management Unit for Human Resources & Institutional Development, Research and Innovation under Contract No. B16F640076; STFC (United Kingdom); Suranaree University of Technology (SUT), Thailand Science Research and Innovation (TSRI), and National Science Research and Innovation Fund (NSRF) under Contract No. 160355; The Royal Society, UK, under Contracts No. DH140054 and No. DH160214; The Swedish Research Council; U.S. Department of Energy under Contract No. DE-FG02-05ER41374.
Publisher Copyright:
© 2022 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP3.
PY - 2022/12/1
Y1 - 2022/12/1
N2 - We report a branching fraction measurement of the singly Cabibbo-suppressed decay Λc+→ΛK+ using a data sample collected with the BESIII detector at the BEPCII storage ring. The data span center-of-mass energies from 4.599 to 4.950 GeV and correspond to an integrated luminosity of 6.44 fb-1. The branching fraction of Λc+→ΛK+ relative to that of the Cabibbo-favored decay Λc+→Λπ+ is measured to be R=B(Λc+→ΛK+)B(Λc+→Λπ+)=(4.78±0.34±0.20)%. Combining with the world-average value of B(Λc+→Λπ+), we obtain B(Λc+→ΛK+)=(6.21±0.44±0.26±0.34)×10-4. Here the first uncertainties are statistical, the second systematic, and the third comes from the uncertainty of the Λc+→Λπ+ branching fraction. This result, which is more precise than previous measurements, does not agree with theoretical predictions, and suggests that nonfactorizable contributions have been underestimated in current models.
AB - We report a branching fraction measurement of the singly Cabibbo-suppressed decay Λc+→ΛK+ using a data sample collected with the BESIII detector at the BEPCII storage ring. The data span center-of-mass energies from 4.599 to 4.950 GeV and correspond to an integrated luminosity of 6.44 fb-1. The branching fraction of Λc+→ΛK+ relative to that of the Cabibbo-favored decay Λc+→Λπ+ is measured to be R=B(Λc+→ΛK+)B(Λc+→Λπ+)=(4.78±0.34±0.20)%. Combining with the world-average value of B(Λc+→Λπ+), we obtain B(Λc+→ΛK+)=(6.21±0.44±0.26±0.34)×10-4. Here the first uncertainties are statistical, the second systematic, and the third comes from the uncertainty of the Λc+→Λπ+ branching fraction. This result, which is more precise than previous measurements, does not agree with theoretical predictions, and suggests that nonfactorizable contributions have been underestimated in current models.
UR - http://www.scopus.com/inward/record.url?scp=85143789224&partnerID=8YFLogxK
U2 - 10.1103/PhysRevD.106.L111101
DO - 10.1103/PhysRevD.106.L111101
M3 - Letter
SN - 2470-0010
VL - 106
JO - Physical Review D
JF - Physical Review D
IS - 11
M1 - L111101
ER -