Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
  • Open Access

Constraints on the unitarity triangle angle γ from Dalitz plot analysis of B0→DK+π− decays

R. Aaij et al. (LHCb Collaboration)
Phys. Rev. D 93, 112018 – Published 30 June 2016; Erratum Phys. Rev. D 94, 079902 (2016)
PDFHTMLExport Citation
Abstract
Erratum
Authors
Article Text
  • INTRODUCTION
  • DETECTOR AND SIMULATION
  • SELECTION
  • DETERMINATION OF SIGNAL AND BACKGROUND…
  • DALITZ PLOT ANALYSIS
  • SYSTEMATIC UNCERTAINTIES
  • RESULTS AND SUMMARY
  • ACKNOWLEDGMENTS
  • APPENDICES
    • References

    Abstract

    The first study is presented of CP violation with an amplitude analysis of the Dalitz plot of B0→DK+π− decays, with D→K+π−, K+K−, and π+π−. The analysis is based on a data sample corresponding to 3.0  fb−1 of pp collisions collected with the LHCb detector. No significant CP violation effect is seen, and constraints are placed on the angle γ of the unitarity triangle formed from elements of the Cabibbo-Kobayashi-Maskawa quark mixing matrix. Hadronic parameters associated with the B0→DK*(892)0 decay are determined for the first time. These measurements can be used to improve the sensitivity to γ of existing and future studies of the B0→DK*(892)0 decay.

    • Figure
    • Figure
    • Figure
    • Figure
    • Figure
    • Figure
    • Figure
    5 More
    • Received 11 February 2016

    DOI:https://doi.org/10.1103/PhysRevD.93.112018

    This article is available under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

    © 2016 CERN, for the LHCb Collaboration

    Physics Subject Headings (PhySH)

    1. Research Areas
    Hadronic decays
    1. Physical Systems
    Bottom mesons
    Particles & Fields

    Erratum

    Erratum: Constraints on the unitarity triangle angle γ from Dalitz plot analysis of B0→DK+π− decays [Phys. Rev. D 93, 112018 (2016)]

    R. Aaij et al. (LHCb Collaboration)
    Phys. Rev. D 94, 079902 (2016)

    Authors & Affiliations

    Click to Expand

    Article Text

    Click to Expand

    References

    Click to Expand
    Issue

    Vol. 93, Iss. 11 — 1 June 2016

    Reuse & Permissions
    Author publication services for translation and copyediting assistance advertisement

    Authorization Required

    Log In
    Other Options
    ×

    Images

    • Figure 1
      Figure 1

      Feynman diagrams for the contributions to B0→DK+π− from (a) B0→D2*(2460)−K+, (b) B0→D¯0K*(892)0, and (c) B0→D0K*(892)0 decays.

      Reuse & Permissions
    • Figure 2
      Figure 2

      Illustration of the method to determine γ from Dalitz plot analysis of B0→DK+π− decays [12, 13]: (left) the Vcb amplitude for B0→D¯0K*0 compared to that for B0→D2*−K+ decay; (right) the effect of the Vub amplitude that contributes to B0→DCPK*0 and B¯0→DCPK¯*0 decays provides sensitivity to γ. The notation DCP represents a neutral D meson reconstructed in a CP eigenstate, while D2CP*− denotes the decay chain D2*−→DCPπ−, where the charge of the pion tags the flavor of the neutral D meson, independently of the mode in which it is reconstructed, so there is no contribution from the Vub amplitude.

      Reuse & Permissions
    • Figure 3
      Figure 3

      Results of fits to DK+π− candidates in the (a,b) D→K+π−, (c,d) D→K+K−, and (e,f) D→π+π− samples. The data and the fit results in each NN output bin have been weighted according to S/(S+B) as described in the text. The left and right plots are identical but with (left) linear and (right) logarithmic y axis scales. The components are as described in the legend.

      Reuse & Permissions
    • Figure 4
      Figure 4

      Results of the fit to DK+π−, D→K+π− candidates shown separately in the five bins of the neural network output variable. The bins are shown, from (a)–(e), in order of increasing S/B. The components are as indicated in the legend. The vertical dotted lines in (a) show the signal window used for the fit to the Dalitz plot.

      Reuse & Permissions
    • Figure 5
      Figure 5

      Results of the fit to DK+π−, D→K+K− candidates shown separately in the five bins of the neural network output variable. The bins are shown, from (a)–(e), in order of increasing S/B. The components are as indicated in the legend. The vertical dotted lines in (a) show the signal window used for the fit to the Dalitz plot.

      Reuse & Permissions
    • Figure 6
      Figure 6

      Results of the fit to DK+π−, D→π+π− candidates shown separately in the five bins of the neural network output variable. The bins are shown, from (a)–(e), in order of increasing S/B. The components are as indicated in the legend. The vertical dotted lines in (a) show the signal window used for the fit to the Dalitz plot.

      Reuse & Permissions
    • Figure 7
      Figure 7

      Dalitz plots for candidates in the B candidate mass signal region in the D→K+K− and π+π− samples for (a) B¯0 and (b) B0 candidates. Only candidates in the three purest NN bins are included. Background has not been subtracted, and therefore some contribution from B¯s0→D*0K+π− decays is expected at low m(DK+) (i.e. along the top right diagonal).

      Reuse & Permissions
    • Figure 8
      Figure 8

      Projections of the D→K+K− and π+π− samples and the fit result onto (a),(b) m(Dπ∓), (c),(d) m(K±π∓), and (e),(f) m(DK±) for (a),(c),(e) B¯0 and (b),(d),(f) B0 candidates. The data and the fit results in each NN output bin have been weighted according to S/(S+B) and combined. The components are described in the legend.

      Reuse & Permissions
    • Figure 9
      Figure 9

      Contours at 68% C.L. for the (blue) (x+,y+) and (red) (x−,y−) parameters associated with the B0→DK*(892)0 decay, with statistical uncertainties only. The central values are marked by a circle and a cross, respectively.

      Reuse & Permissions
    • Figure 10
      Figure 10

      Results of likelihood scans for (a) γ, (b) rB, and (c) δB.

      Reuse & Permissions
    • Figure 11
      Figure 11

      Confidence level contours for (a) γ and rB, (b) γ and δB, and (c) rB and δB. The shaded regions are allowed at 68% C.L.

      Reuse & Permissions
    • Figure 12
      Figure 12

      Distributions of (a) κ, (b) R¯B, and (c) Δδ¯B, obtained as described in the text.

      Reuse & Permissions
    ×

    Sign up to receive regular email alerts from Physical Review D

    Reuse & Permissions

    It is not necessary to obtain permission to reuse this article or its components as it is available under the terms of the Creative Commons Attribution 3.0 License. This license permits unrestricted use, distribution, and reproduction in any medium, provided attribution to the author(s) and the published article's title, journal citation, and DOI are maintained. Please note that some figures may have been included with permission from other third parties. It is your responsibility to obtain the proper permission from the rights holder directly for these figures.

    ×

    Log In

    Cancel
    ×

    Search

    Article Lookup

    Paste a citation or DOI
    Enter a citation
    ×