The ratio of branching fractions $R_{K/\pi} \equiv \mathcal{B}(B_{c}^{+} \to J/\psi K^{+})/\mathcal{B}(B_{c}^{+} \to J/\psi\pi^{+})$ is measured with $pp$ collision data collected by the LHCb experiment at centre-of-mass energies of 7 TeV and 8 TeV, corresponding to an integrated luminosity of 3${ fb^{-1}}$. It is found to be $ R_{K/\pi} = 0.079\pm0.007\pm0.003$, where the first uncertainty is statistical and the second is systematic. This measurement is consistent with the previous LHCb result, while the uncertainties are significantly reduced.
Fits to the reconstructed $ B _ c ^+ \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} K ^+ $ (left) and $ B _ c ^+ \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} \pi ^+ $ (right) mass distributions using 7 TeV (top) and 8 TeV (bottom) data samples. The contributions from the signal, the misidentification background, the combinatorial background and the partially reconstructed background are indicated in the figures. |
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Animated gif made out of all figures. |
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Summary of the relative systematic uncertainties on $ {R}_{K/\pi} $. |
Table_1.pdf [24 KiB] HiDef png [97 KiB] Thumbnail [43 KiB] tex code |
Created on 26 April 2024.