Observation of CP violation in two-body $$ {B}_{(s)}^0 $$-meson decays to charged pions and kaons

Journal article

A bstract The time-dependent CP asymmetries of B 0 → π + π − and $$ {B}_s^0 $$ Bs0 → K + K − decays are measured using a data sample of pp collisions corresponding to an integrated luminosity of 1.9 fb − 1 , collected with the LHCb detector at a centre-of-mass energy of 13 TeV. The results are $$ {\displaystyle \begin{array}{c}{C}_{\pi \pi}=-0.311\pm 0.045\pm 0.015,\\ {}{S}_{\pi \pi}=-0.706\pm 0.042\pm 0.013,\\ {}{C}_{KK}=0.123\pm 0.034\pm 0.015,\\ {}{S}_{KK}=0.164\pm 0.034\pm 0.014,\\ {}{\mathcal{A}}_{KK}^{\Delta \varGamma }=-0.83\pm 0.05\pm 0.09,\end{array}} $$ Cππ=−0.311±0.045±0.015,Sππ=−0.706±0.042±0.013,CKK=0.123±0.034±0.015,SKK=0.164±0.034±0.014,AKKΔΓ=−0.83±0.05±0.09, where the first uncertainties are statistical and the second systematic. The same data sample is used to measure the time-integrated CP asymmetries of B 0 → K + π − and $$ {B}_s^0 $$ Bs0 → K − π + decays and the results are $$ {\displaystyle \begin{array}{c}{A}_{CP}^{B^0}=-0.0824\pm 0.0033\pm 0.0033,\\ {}{A}_{CP}^{B_s^0}=0.236\pm 0.013\pm 0.011.\end{array}} $$ ACPB0=−0.0824±0.0033±0.0033,ACPBs0=0.236±0.013±0.011. All results are consistent with earlier measurements. A combination of LHCb measurements provides the first observation of time-dependent CP violation in $$ {B}_s^0 $$ Bs0 decays.

Authors: Aaij, R; Abellán Beteta, C; Ackernley, T; Adeva, B; Adinolfi, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Springer
• Journal: Journal of High Energy Physics
• Volume: 2021
• Issue: 3
• Pages: 75
• Article number: 75
• Publication date: 2021-03-08
• DOI: 10.1007/jhep03(2021)075
• EISSN: 1029-8479
• ISSN: 1126-6708
• Language: English