First Observation of the B ¯ s0 → Λc+ Λ ¯ c- Decay and Evidence for the B ¯ 0 → Λc+ Λ ¯ c- Decay

LHCb Collaboration

doi:10.1103/cxn3-8t4g

First Observation of the B ¯ s0 → Λc+ Λ ¯ c- Decay and Evidence for the B ¯ 0 → Λc+ Λ ¯ c- Decay

LHCb Collaboration

National Institute for Subatomic Physics
University of Warwick
University of Zurich
University of Liverpool
Syracuse University
Instituto Galego de Física de Altas Enerxías (IGFAE)
University of Bristol
University of Glasgow
Uppsala University
Université Paris-Saclay
University of Michigan, Ann Arbor
Université Clermont Auvergne
AGH University of Krakow
National Institute for Nuclear Physics
TU Dortmund University
Lamarr Institute for Machine Learning and Artificial Intelligence
University of Freiburg
Vilnius University
CERN
University of Cambridge
Sorbonne Université
Universidade Federal do Rio de Janeiro
Peking University
University of A Coruna
University of Milan - Bicocca
University of Chinese Academy of Sciences
Consejo Nacional de Rectores (CONARE)
CPPM
Swiss Federal Institute of Technology Lausanne
Massachusetts Institute of Technology
Laboratoire Leprince-Ringuet
University of Oxford
Heidelberg University
Ruhr University Bochum
Centro Brasileiro de Pesquisas Físicas
Pontifícia Universidade Católica do Rio de Janeiro
University of Manchester
University of Edinburgh
CAS - Institute of High Energy Physics
Eötvös Loránd University
Ramon Llull University
Kyiv National Taras Shevchenko University
University of Bonn
Imperial College London
Université Savoie Mont Blanc
University of Modena and Reggio Emilia
University of Victoria BC
Los Alamos National Laboratory
Maastricht University
University of Ferrara
Monash University
Henryk Niewodniczanski Institute of Nuclear Physics of the Polish Academy of Sciences
Cracow University of Technology
Ohio State University
Tsinghua University
Wuhan University
University of Barcelona
Universidade Estadual de Campinas
University of Bologna
University of Genoa
Scuola Normale Superiore di Pisa
University of Milan
NASU - Institute of Nuclear Research
Horia Hulubei National Institute of Physics and Nuclear Engineering
University of Cincinnati
National Autonomous University of Honduras
Central China Normal University
Hunan University
University of Cagliari
University of Groningen
Centro Federal de Educação Tecnológica Celso Suckow da Fonseca
University of Bari
University College Dublin
South China Normal University
Rutherford Appleton Laboratory
University of Perugia
University of Valencia
University of Maryland, College Park
NASU - Kharkov Institute of Physics and Technology
National Centre for Nuclear Research
RWTH Aachen University
Universidad Nacional de Colombia
Czech Academy of Sciences
University of Birmingham
Vrije Universiteit Amsterdam
University of Pisa
Henan Normal University
Lanzhou University
University of Padua
University of Bergamo
Universidad de Ingeniería y Tecnología
University of Siena
Max Planck Institute for Nuclear Physics
University of Alcalá
University of Urbino
Universidad Andrés Bello

Research output: Contribution to journal › Article › peer-review

Abstract

A search is presented for the two-body charmed baryonic decays, B¯(s)0→Λc+Λ¯c-, using a data sample collected by the LHCb experiment during 2011-2012 and 2015-2018, corresponding to an integrated luminosity of 9 fb-1. The first observation of the B¯s0→Λc+Λ¯c- decay is reported with 6.2σ significance along with 4.3σ evidence for the B¯0→Λc+Λ¯c- decay. The branching fractions are measured to be B(B¯0→Λc+Λ¯c-)=(1.01-0.28+0.27±0.08±0.15)×10-5 and B(B¯s0→Λc+Λ¯c-)=(5.0±1.3±0.5±0.8)×10-5, where the first uncertainty is statistical, the second systematic, and the third due to external inputs. These results provide novel experimental inputs for the theoretical framework describing two-body baryonic decays of B mesons via W-emission and W-exchange mechanisms.

Original language	English
Article number	061802
Journal	Physical Review Letters
Volume	136
Issue number	6
DOIs	https://doi.org/10.1103/cxn3-8t4g
State	Published - 13 Feb 2026
Externally published	Yes

Access to Document

10.1103/cxn3-8t4g

Cite this

@article{97dc89f7c8b9446eb0b643546b3d81e5,

title = "First Observation of the B ¯ s0 → Λc+ Λ ¯ c- Decay and Evidence for the B ¯ 0 → Λc+ Λ ¯ c- Decay",

abstract = "A search is presented for the two-body charmed baryonic decays, B¯(s)0→Λc+Λ¯c-, using a data sample collected by the LHCb experiment during 2011-2012 and 2015-2018, corresponding to an integrated luminosity of 9 fb-1. The first observation of the B¯s0→Λc+Λ¯c- decay is reported with 6.2σ significance along with 4.3σ evidence for the B¯0→Λc+Λ¯c- decay. The branching fractions are measured to be B(B¯0→Λc+Λ¯c-)=(1.01-0.28+0.27±0.08±0.15)×10-5 and B(B¯s0→Λc+Λ¯c-)=(5.0±1.3±0.5±0.8)×10-5, where the first uncertainty is statistical, the second systematic, and the third due to external inputs. These results provide novel experimental inputs for the theoretical framework describing two-body baryonic decays of B mesons via W-emission and W-exchange mechanisms.",

author = "\{LHCb Collaboration\} and R. Aaij and Abdelmotteleb, \{A. S.W.\} and \{Abellan Beteta\}, C. and F. Abudin{\'e}n and T. Ackernley and Adefisoye, \{A. A.\} and B. Adeva and M. Adinolfi and P. Adlarson and C. Agapopoulou and Aidala, \{C. A.\} and Z. Ajaltouni and S. Akar and K. Akiba and M. Akthar and P. Albicocco and J. Albrecht and R. Aleksiejunas and F. Alessio and \{Alvarez Cartelle\}, P. and R. Amalric and S. Amato and Amey, \{J. L.\} and Y. Amhis and L. An and L. Anderlini and M. Andersson and P. Andreola and M. Andreotti and \{Andres Estrada\}, S. and A. Anelli and D. Ao and C. Arata and F. Archilli and Z. Areg and M. Argenton and \{Arguedas Cuendis\}, S. and L. Arnone and A. Artamonov and M. Artuso and E. Aslanides and \{Ata{\'i}de Da Silva\}, R. and M. Atzeni and B. Audurier and Authier, \{J. A.\} and D. Bacher and \{Bachiller Perea\}, I. and S. Bachmann and M. Bachmayer and \{Calderon Ramirez\}, S.",

note = "Publisher Copyright: {\textcopyright} 2026 CERN, for the LHCb Collaboration. 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 SCOAP",

year = "2026",

month = feb,

day = "13",

doi = "10.1103/cxn3-8t4g",

language = "Ingl{\'e}s",

volume = "136",

journal = "Physical Review Letters",

issn = "0031-9007",

number = "6",

}

TY - JOUR

T1 - First Observation of the B ¯ s0 → Λc+ Λ ¯ c- Decay and Evidence for the B ¯ 0 → Λc+ Λ ¯ c- Decay

AU - LHCb Collaboration

AU - Aaij, R.

AU - Abdelmotteleb, A. S.W.

AU - Abellan Beteta, C.

AU - Abudinén, F.

AU - Ackernley, T.

AU - Adefisoye, A. A.

AU - Adeva, B.

AU - Adinolfi, M.

AU - Adlarson, P.

AU - Agapopoulou, C.

AU - Aidala, C. A.

AU - Ajaltouni, Z.

AU - Akar, S.

AU - Akiba, K.

AU - Akthar, M.

AU - Albicocco, P.

AU - Albrecht, J.

AU - Aleksiejunas, R.

AU - Alessio, F.

AU - Alvarez Cartelle, P.

AU - Amalric, R.

AU - Amato, S.

AU - Amey, J. L.

AU - Amhis, Y.

AU - An, L.

AU - Anderlini, L.

AU - Andersson, M.

AU - Andreola, P.

AU - Andreotti, M.

AU - Andres Estrada, S.

AU - Anelli, A.

AU - Ao, D.

AU - Arata, C.

AU - Archilli, F.

AU - Areg, Z.

AU - Argenton, M.

AU - Arguedas Cuendis, S.

AU - Arnone, L.

AU - Artamonov, A.

AU - Artuso, M.

AU - Aslanides, E.

AU - Ataíde Da Silva, R.

AU - Atzeni, M.

AU - Audurier, B.

AU - Authier, J. A.

AU - Bacher, D.

AU - Bachiller Perea, I.

AU - Bachmann, S.

AU - Bachmayer, M.

AU - Calderon Ramirez, S.

N1 - Publisher Copyright: © 2026 CERN, for the LHCb Collaboration. 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 SCOAP

PY - 2026/2/13

Y1 - 2026/2/13

N2 - A search is presented for the two-body charmed baryonic decays, B¯(s)0→Λc+Λ¯c-, using a data sample collected by the LHCb experiment during 2011-2012 and 2015-2018, corresponding to an integrated luminosity of 9 fb-1. The first observation of the B¯s0→Λc+Λ¯c- decay is reported with 6.2σ significance along with 4.3σ evidence for the B¯0→Λc+Λ¯c- decay. The branching fractions are measured to be B(B¯0→Λc+Λ¯c-)=(1.01-0.28+0.27±0.08±0.15)×10-5 and B(B¯s0→Λc+Λ¯c-)=(5.0±1.3±0.5±0.8)×10-5, where the first uncertainty is statistical, the second systematic, and the third due to external inputs. These results provide novel experimental inputs for the theoretical framework describing two-body baryonic decays of B mesons via W-emission and W-exchange mechanisms.

AB - A search is presented for the two-body charmed baryonic decays, B¯(s)0→Λc+Λ¯c-, using a data sample collected by the LHCb experiment during 2011-2012 and 2015-2018, corresponding to an integrated luminosity of 9 fb-1. The first observation of the B¯s0→Λc+Λ¯c- decay is reported with 6.2σ significance along with 4.3σ evidence for the B¯0→Λc+Λ¯c- decay. The branching fractions are measured to be B(B¯0→Λc+Λ¯c-)=(1.01-0.28+0.27±0.08±0.15)×10-5 and B(B¯s0→Λc+Λ¯c-)=(5.0±1.3±0.5±0.8)×10-5, where the first uncertainty is statistical, the second systematic, and the third due to external inputs. These results provide novel experimental inputs for the theoretical framework describing two-body baryonic decays of B mesons via W-emission and W-exchange mechanisms.

UR - https://www.scopus.com/pages/publications/105030332981

U2 - 10.1103/cxn3-8t4g

DO - 10.1103/cxn3-8t4g

M3 - Artículo

AN - SCOPUS:105030332981

SN - 0031-9007

VL - 136

JO - Physical Review Letters

JF - Physical Review Letters

IS - 6

M1 - 061802

ER -

First Observation of the B ¯ s0 → Λc+ Λ ¯ c- Decay and Evidence for the B ¯ 0 → Λc+ Λ ¯ c- Decay

Abstract

Access to Document

Other files and links

Fingerprint

Cite this