Электронный каталог

Статья

Aaij, R.
Measurement of the Branching Fraction Ratio R&sub(K) at Large Dilepton Invariant Mass / R.Aaij, K.Ivshin, A.Solovev, [LHCb Collab.]. – Text : electronic // Journal of High Energy Physics. – 2025. – Vol. 2025, No. 7. – P. 198. – URL: https://doi.org/10.1007/JHEP07(2025)198. – Bibliogr.: 75.

A test of lepton universality between muons and electrons is performed using B*+→ K*+ℓ*+ℓ*− decays (where ℓ = e, µ), in the dilepton invariant-mass-squared region above 14.3 GeV*2 /c*4 . The data used for the measurement consists of beauty meson decays produced in proton-proton collisions, corresponding to an integrated luminosity of 9 fb*−*1 , collected by the LHCb experiment between 2011 and 2018. The ratio of branching fractions for B*+→ K*+µ*+µ*− and B*+→ K*+e*+e*− decays is measured to be RK = 1.08&sup(+0.11)&sub(−0.09) (stat)&sup(+0.04)&sub(−0.04) (syst), which is consistent with the Standard Model prediction of unity. This constitutes the most precise test of lepton favour universality using B*+→ K*+ℓ* +ℓ*− decays with dilepton invariant-masssquared above the ψ(2S) mass, whilst being the frst of its kind at a hadron collider.



ОИЯИ = ОИЯИ (JINR)2025
Спец.(статьи,препринты) = С 346.2в - Взаимодействие протонов с протонами
Спец.(статьи,препринты) = С 346.6 - Резонансы и новые частицы