RT Journal Article
T1 Differential branching fraction and angular analysis of Λ 0b → Λμ+μ− decays
A1 LHCb Collaboration, 
A1 Adeva Andany, Bernardo
A1 Dosil Suárez, Álvaro
A1 Fernández Albor, Víctor Manuel
A1 Gallas Torreira, Abraham Antonio
A1 García Pardiñas, Julián
A1 Hernando Morata, José Ángel
A1 Plo Casasus, Máximo
A1 Romero Vidal, Antonio
A1 Saborido Silva, Juan José
A1 Sanmartín Sedes, Brais
A1 Santamarina Ríos, Cibrán
A1 Vázquez Regueiro, Pablo
A1 Vázquez Sierra, Carlos
A1 Vieites Díaz, María
K1 Rare decay
K1 Hadron-Hadron Scattering
K1 Branching fraction
K1 B physics
K1 Flavour Changing Neutral Currents
AB The differential branching fraction of the rare decay Λ 0b → Λμ+μ− is measured as a function of q2, the square of the dimuon invariant mass. The analysis is performed using proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb−1, collected by the LHCb experiment. Evidence of signal is observed in the q2 region below the square of the J/ψ mass. Integrating over 15 < q2 < 20 GeV2/c4 the differential branching fraction is measured asdB(Λ0b→Λμ+μ−)/dq2=(1.18+0.09−0.08±0.03±0.27)×10−7(GeV2/c4)−1,where the uncertainties are statistical, systematic and due to the normalisation mode, Λ 0b → J/ψΛ, respectively. In the q2 intervals where the signal is observed, angular distributions are studied and the forward-backward asymmetries in the dimuon (A ℓFB) and hadron (A hFB) systems are measured for the first time. In the range 15 < q2 < 20 GeV2/c4 they are found to beAℓFB=−0.05±0.09(stat)±0.03(syst)andAhFB=−0.29±0.07(stat)±0.03(syst).
PB Springer
SN 1029-8479
YR 2015
FD 2015
LK http://hdl.handle.net/10347/21984
UL http://hdl.handle.net/10347/21984
LA eng
NO Aaij, R., Adeva, B., Adinolfi, M. et al. Differential branching fraction and angular analysis of Λ 0b → Λμ+μ− decays. J. High Energ. Phys. 2015, 115 (2015). https://doi.org/10.1007/JHEP06(2015)115
DS Minerva
RD 3 may 2026