cern.ch

Measurement of the ratio of branching fractions $\mathcal{B}(B_c^+ \to J/\psi\tau^+\nu_\tau)$/$\mathcal{B}(B_c^+ \to J/\psi\mu^+\nu_\mu)$

[to restricted-access page]

Abstract

A measurement is reported of the ratio of branching fractions $\mathcal{R}(J/\psi)=\mathcal{B}(B_c^+ \to J/\psi\tau^+\nu_\tau)/\mathcal{B}(B_c^+ \to J/\psi \mu^+\nu_\mu)$, where the $\tau^+$ lepton is identified in the decay mode $\tau^+ \to \mu^+\nu_\mu\overline{\nu}_\tau$. This analysis uses a sample of proton-proton collision data corresponding to 3.0$\mathrm{ fb}^{-1}$ of integrated luminosity recorded with the LHCb experiment at center-of-mass energies $7 \mathrm{TeV}$ and $8 \mathrm{TeV}$. A signal is found for the decay $B_c^+ \to J/\psi \tau^+\nu_\tau$ at a significance of 3 standard deviations, corrected for systematic uncertainty, and the ratio of the branching fractions is measured to be $\mathcal{R}(J/\psi) = 0.71 \pm 0.17 \mathrm{ (stat)} \pm 0.18\mathrm{ (syst)}$. This result lies within 2 standard deviations above the range of existing predictions in the Standard Model.

Figures and captions

Distributions of (top) $ m_\mathrm{miss}^2$ , (middle) decay time, and (bottom) $Z$ of the signal data, overlaid with projections of the fit model with all normalization and shape parameters at their best-fit values. Below each panel differences between the data and fit are shown, normalized by the Poisson uncertainty in the data; the dashed lines are at the values $\pm 2$.

Fig1a.pdf [18 KiB]
HiDef png [156 KiB]
Thumbnail [157 KiB]
*.C file
Fig1a.pdf
Fig1b.pdf [15 KiB]
HiDef png [146 KiB]
Thumbnail [145 KiB]
*.C file
Fig1b.pdf
Fig1c.pdf [15 KiB]
HiDef png [146 KiB]
Thumbnail [147 KiB]
*.C file
Fig1c.pdf
Fig1_l[..].pdf [13 KiB]
HiDef png [100 KiB]
Thumbnail [96 KiB]
*.C file
Fig1_legend.pdf

Animated gif made out of all figures.

PAPER-2017-035.gif
Thumbnail
thumbnail_PAPER-2017-035.gif

Tables and captions

Systematic uncertainties in the determination of $\mathcal{R}( { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} )$ .

Table_1.pdf [77 KiB]
HiDef png [128 KiB]
Thumbnail [61 KiB]
tex code
Table_1.pdf

Supplementary Material [file]

Supplementary material full pdf

supple[..].pdf [875 KiB]
supplementary.pdf

This ZIP file contains supplemetary material for the publication LHCb-PAPER-2017-035. The files are: supplementary.pdf : An overview of the extra figures *.pdf, *.png, *.eps, *.C : The figures in variuous formats

Fig1a.pdf [18 KiB]
HiDef png [166 KiB]
Thumbnail [172 KiB]
*C file
Fig1a.pdf
Fig1b.pdf [15 KiB]
HiDef png [134 KiB]
Thumbnail [136 KiB]
*C file
Fig1b.pdf
Fig1c.pdf [17 KiB]
HiDef png [155 KiB]
Thumbnail [158 KiB]
*C file
Fig1c.pdf
Fig1d.pdf [15 KiB]
HiDef png [145 KiB]
Thumbnail [150 KiB]
*C file
Fig1d.pdf
Fig1e.pdf [17 KiB]
HiDef png [152 KiB]
Thumbnail [153 KiB]
*C file
Fig1e.pdf
Fig1f.pdf [15 KiB]
HiDef png [135 KiB]
Thumbnail [138 KiB]
*C file
Fig1f.pdf
Fig1g.pdf [17 KiB]
HiDef png [138 KiB]
Thumbnail [138 KiB]
*C file
Fig1g.pdf
Fig1h.pdf [15 KiB]
HiDef png [139 KiB]
Thumbnail [142 KiB]
*C file
Fig1h.pdf
Fig2a.pdf [17 KiB]
HiDef png [144 KiB]
Thumbnail [150 KiB]
*C file
Fig2a.pdf
Fig2b.pdf [14 KiB]
HiDef png [130 KiB]
Thumbnail [129 KiB]
*C file
Fig2b.pdf
Fig2c.pdf [17 KiB]
HiDef png [154 KiB]
Thumbnail [159 KiB]
*C file
Fig2c.pdf
Fig2d.pdf [15 KiB]
HiDef png [147 KiB]
Thumbnail [149 KiB]
*C file
Fig2d.pdf
Fig2e.pdf [18 KiB]
HiDef png [160 KiB]
Thumbnail [166 KiB]
*C file
Fig2e.pdf
Fig2f.pdf [15 KiB]
HiDef png [156 KiB]
Thumbnail [159 KiB]
*C file
Fig2f.pdf
Fig2g.pdf [17 KiB]
HiDef png [148 KiB]
Thumbnail [152 KiB]
*C file
Fig2g.pdf
Fig2h.pdf [15 KiB]
HiDef png [143 KiB]
Thumbnail [148 KiB]
*C file
Fig2h.pdf
Fig3.pdf [14 KiB]
HiDef png [127 KiB]
Thumbnail [120 KiB]
*C file
Fig3.pdf
Fig4a.pdf [14 KiB]
HiDef png [564 KiB]
Thumbnail [332 KiB]
*C file
Fig4a.pdf
Fig4b.pdf [15 KiB]
HiDef png [476 KiB]
Thumbnail [291 KiB]
*C file
Fig4b.pdf
Fig4c.pdf [14 KiB]
HiDef png [578 KiB]
Thumbnail [340 KiB]
*C file
Fig4c.pdf
Fig4d.pdf [15 KiB]
HiDef png [620 KiB]
Thumbnail [370 KiB]
*C file
Fig4d.pdf
Fig4e.pdf [14 KiB]
HiDef png [711 KiB]
Thumbnail [394 KiB]
*C file
Fig4e.pdf
Fig4f.pdf [15 KiB]
HiDef png [667 KiB]
Thumbnail [373 KiB]
*C file
Fig4f.pdf
Fig5a.pdf [15 KiB]
HiDef png [135 KiB]
Thumbnail [134 KiB]
*C file
Fig5a.pdf
Fig5b.pdf [15 KiB]
HiDef png [150 KiB]
Thumbnail [152 KiB]
*C file
Fig5b.pdf
Fig5c.pdf [15 KiB]
HiDef png [135 KiB]
Thumbnail [137 KiB]
*C file
Fig5c.pdf
Fig6a.pdf [16 KiB]
HiDef png [353 KiB]
Thumbnail [249 KiB]
*C file
Fig6a.pdf
Fig6b.pdf [14 KiB]
HiDef png [562 KiB]
Thumbnail [356 KiB]
*C file
Fig6b.pdf
Fig6c.pdf [14 KiB]
HiDef png [580 KiB]
Thumbnail [365 KiB]
*C file
Fig6c.pdf
Fig6d.pdf [16 KiB]
HiDef png [323 KiB]
Thumbnail [222 KiB]
*C file
Fig6d.pdf
Fig6e.pdf [14 KiB]
HiDef png [462 KiB]
Thumbnail [301 KiB]
*C file
Fig6e.pdf
Fig6f.pdf [14 KiB]
HiDef png [497 KiB]
Thumbnail [328 KiB]
*C file
Fig6f.pdf
Fig7ai.pdf [16 KiB]
HiDef png [472 KiB]
Thumbnail [303 KiB]
*C file
Fig7ai.pdf
Fig7aii.pdf [14 KiB]
HiDef png [812 KiB]
Thumbnail [429 KiB]
*C file
Fig7aii.pdf
Fig7aiii.pdf [14 KiB]
HiDef png [852 KiB]
Thumbnail [489 KiB]
*C file
Fig7aiii.pdf
Fig7bi.pdf [16 KiB]
HiDef png [494 KiB]
Thumbnail [305 KiB]
*C file
Fig7bi.pdf
Fig7bii.pdf [14 KiB]
HiDef png [716 KiB]
Thumbnail [406 KiB]
*C file
Fig7bii.pdf
Fig7biii.pdf [14 KiB]
HiDef png [803 KiB]
Thumbnail [477 KiB]
*C file
Fig7biii.pdf
Fig7ci.pdf [16 KiB]
HiDef png [420 KiB]
Thumbnail [306 KiB]
*C file
Fig7ci.pdf
Fig7cii.pdf [14 KiB]
HiDef png [694 KiB]
Thumbnail [420 KiB]
*C file
Fig7cii.pdf
Fig7ciii.pdf [14 KiB]
HiDef png [748 KiB]
Thumbnail [520 KiB]
*C file
Fig7ciii.pdf
Fig7di.pdf [16 KiB]
HiDef png [544 KiB]
Thumbnail [307 KiB]
*C file
Fig7di.pdf
Fig7dii.pdf [14 KiB]
HiDef png [810 KiB]
Thumbnail [429 KiB]
*C file
Fig7dii.pdf
Fig7diii.pdf [14 KiB]
HiDef png [876 KiB]
Thumbnail [505 KiB]
*C file
Fig7diii.pdf
Fig8ai.pdf [16 KiB]
HiDef png [491 KiB]
Thumbnail [295 KiB]
*C file
Fig8ai.pdf
Fig8aii.pdf [14 KiB]
HiDef png [688 KiB]
Thumbnail [390 KiB]
*C file
Fig8aii.pdf
Fig8aiii.pdf [14 KiB]
HiDef png [798 KiB]
Thumbnail [454 KiB]
*C file
Fig8aiii.pdf
Fig8bi.pdf [16 KiB]
HiDef png [456 KiB]
Thumbnail [285 KiB]
*C file
Fig8bi.pdf
Fig8bii.pdf [14 KiB]
HiDef png [645 KiB]
Thumbnail [385 KiB]
*C file
Fig8bii.pdf
Fig8biii.pdf [14 KiB]
HiDef png [739 KiB]
Thumbnail [441 KiB]
*C file
Fig8biii.pdf
Fig8ci.pdf [16 KiB]
HiDef png [532 KiB]
Thumbnail [306 KiB]
*C file
Fig8ci.pdf
Fig8cii.pdf [14 KiB]
HiDef png [797 KiB]
Thumbnail [439 KiB]
*C file
Fig8cii.pdf
Fig8ciii.pdf [14 KiB]
HiDef png [869 KiB]
Thumbnail [498 KiB]
*C file
Fig8ciii.pdf
Fig9.pdf [67 KiB]
HiDef png [353 KiB]
Thumbnail [296 KiB]
*C file
Fig9.pdf

Created on 19 October 2019.