Measurement of the Mass Difference Between Neutral Charm-Meson Eigenstates

Aaij, R, Beteta, C Abellan, Adeva, B, Adinolfi, M, Aidala, CA, Ajaltouni, Z, Akar, S, Albicocco, P, Albrecht, J, Alessio, F
et al (show 834 more authors) (2019) Measurement of the Mass Difference Between Neutral Charm-Meson Eigenstates. PHYSICAL REVIEW LETTERS, 122 (23). 231802-.

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We report a measurement of the mass difference between neutral charm-meson eigenstates using a novel approach that enhances sensitivity to this parameter. We use 2.3×10^{6} D^{0}→K_{S}^{0}π^{+}π^{-} decays reconstructed in proton-proton collisions collected by the LHCb experiment in 2011 and 2012. Allowing for CP violation in mixing and in the interference between mixing and decay, we measure the CP-averaged normalized mass difference x_{CP}=[2.7±1.6(stat)±0.4(syst)]×10^{-3} and the CP-violating parameter Δx=[-0.53±0.70(stat)±0.22(syst)]×10^{-3}. The results are consistent with CP symmetry. These determinations are the most precise from a single experiment and, combined with current world-average results, yield the first evidence that the masses of the neutral charm-meson eigenstates differ.

Item Type: Article
Additional Information: All figures and tables, along with any supplementary material and additional information, are available at (LHCb public pages)
Uncontrolled Keywords: LHCb Collaboration
Depositing User: Symplectic Admin
Date Deposited: 30 Sep 2019 09:26
Last Modified: 19 Jan 2023 00:25
DOI: 10.1103/PhysRevLett.122.231802
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