Abstract
We report the measurements of the CP -violating parameters in B 0 s → D ∓ s K± decays observed in pp collisions, using a data set corresponding to an integrated luminosity of 3.0 fb−1 recorded with the LHCb detector. We measure Cf = 0.73 ± 0.14 ± 0.05, A ΔΓ f = 0.39 ± 0.28 ± 0.15, \( {A}_{\overline{f}}^{\varDelta \varGamma }=0.31\pm 0.28\pm 0.15 \), Sf = −0.52 ± 0.20 ± 0.07, \( {S}_{\overline{f}}=-0.49\pm 0.20\pm 0.07 \), where the uncertainties are statistical and systematic, respectively. These parameters are used together with the world-average value of the B 0 s mixing phase, −2βs, to obtain a measurement of the CKM angle γ from B 0 s → D ∓ s K± decays, yielding γ = (128 + 17− 22 )° modulo 180°, where the uncertainty contains both statistical and systematic contributions. This corresponds to 3.8 σ evidence for CP violation in the interference between decay and decay after mixing.
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ArXiv ePrint: 1712.07428
C. Baesso, C. Göbel, V. Salustino Guimaraes are associated to Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
N. Beliy, J. He, W. Huang, P.-R. Li, X. Lyu, J. Qin, M. Szymanski, D. Vieira, Q. Xu, Y. Zheng, H. Cai, L. Sun, B. Dey, W. Hu, Y. Wang, Y. Xie, M. Xu, H. Yin, J. Yu are associated to Center for High Energy Physics, Tsinghua University, Beijing, China.
D. A. Milanes, I.A. Monroy, J.A. Rodriguez Lopez are associated to LPNHE, Université Pierre et Marie Curie, Université Paris Diderot, CNRS/IN2P3, Paris, France.
O. Grünberg, M. Heß, N. Meinert, H. Viemann, R. Waldi are associated to Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany.
T. Likhomanenko, A. Malinin, O. Morgunova, A. Nogay, A. Petrov, V. Shevchenko, A. Vagner are associated to Institute of Theoretical and Experimental Physics (ITEP), Moscow, Russia.
L.M. Garcia Martin, L. Henry, F. Martinez Vidal, A. Oyanguren, C. Remon Alepuz, P. Ruiz Valls, J. Ruiz Vidal, C. Sanchez Mayordomo are associated to ICCUB, Universitat de Barcelona, Barcelona, Spain.
C.J.G. Onderwater are associated to Nikhef National Institute for Subatomic Physics, Amsterdam, The Netherlands.
C.L. Da Silva, J.M. Durham are associated to Syracuse University, Syracuse, NY, United States.
Deceased (I. Raniuk).
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The LHCb collaboration., Aaij, R., Adeva, B. et al. Measurement of CP asymmetry in B 0 s → D ∓ s K± decays. J. High Energ. Phys. 2018, 59 (2018). https://doi.org/10.1007/JHEP03(2018)059
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DOI: https://doi.org/10.1007/JHEP03(2018)059