# Searches for $B^0_{(s)} \to J/\psi p\bar{p}$ and $B^+ \to J/\psi p\bar{p}\pi^+$ decays

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## Abstract

The results of searches for $B^{0}_{(s)} \rightarrow J/{\psi} p \overline{p}$ and $B^{+} \to J/{\psi} p \overline{p} {\pi}^{+}$ decays are reported. The analysis is based on a data sample, corresponding to an integrated luminosity of 1.0 fb$^{-1}$ of $pp$ collisions, collected with the LHCb detector. An excess with 2.8$\sigma$ significance is seen for the decay $B^{0}_{s} \to J/{\psi} p \overline{p}$ and an upper limit on the branching fraction is set at the 90 confidence level: ${\cal B}(B^{0}_{s} \to J/{\psi} p \overline{p}) < 4.8 \times 10^{-6}$, which is the first such limit. No significant signals are seen for $B^{0} \to J/{\psi} p \overline{p}$ and $B^{+} \to J/{\psi} p \overline{p} {\pi}^{+}$ decays, for which the corresponding limits are set: ${\cal{B}}(B^{0} \to J/{\psi} p \overline{p}) < 5.2 \times 10^{-7}$, which significantly improves the existing limit; and ${\cal{B}}(B^{+} \to J/{\psi} p \overline{p} {\pi}^{+}) < 5.0 \times 10^{-7}$, which is the first limit on this branching fraction.

## Figures and captions

 Invariant mass distribution of (a) $B ^0_{( s )} \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} p \overline p$ and (b) $B ^+ \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} p \overline p \pi ^+$ candidates after the full selection. Each component of the fit model is displayed on the plot: the signal PDFs are represented by the dot-dashed violet and dashed green line; the combinatorial background by the dotted red line; and the overall fit is given by the solid blue line. The fit pulls are also shown, with the red lines corresponding to $2 \sigma$. The $B ^+ \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} p \overline p \pi ^+$ yield is multiplied by five in order to make the signal position visible. Fig1a.pdf [26 KiB] HiDef png [278 KiB] Thumbnail [239 KiB] *.C file Fig1b.pdf [28 KiB] HiDef png [263 KiB] Thumbnail [227 KiB] *.C file Invariant mass distribution of $B ^0_{( s )} \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} \pi ^+ \pi ^-$ candidates after the full selection for the (a) $B ^0_{( s )} \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} p \overline p$ and (c) $B ^+ \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} p \overline p \pi ^+$ searches. The corresponding logarithmic plots are shown in (b) and (d). Each component of the fit is represented on the plot: $B ^0 \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} \pi ^+ \pi ^-$ signal (green dashed), $B ^0_ s \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} \pi ^+ \pi ^-$ signal (violet dot-dashed), $B ^0 \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} K ^+ \pi ^-$ background (black falling hashed), ${ B ^0_ s \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} \eta' }$ background (cyan rising hashed), and combinatorial background (red dotted). The overall fit is represented by the solid blue line. Fig2a.pdf [23 KiB] HiDef png [238 KiB] Thumbnail [169 KiB] *.C file Fig2b.pdf [21 KiB] HiDef png [382 KiB] Thumbnail [262 KiB] *.C file Fig2c.pdf [23 KiB] HiDef png [255 KiB] Thumbnail [179 KiB] *.C file Fig2d.pdf [21 KiB] HiDef png [420 KiB] Thumbnail [276 KiB] *.C file Negative log-likelihood profiles for the (a) $B ^0 \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} p \overline p$ , (b) $B ^0_ s \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} p \overline p$ , and (c) $B ^+ \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} p \overline p \pi ^+$ signal yields. The red dashed line corresponds to the statistical-only profile while the blue line includes all the systematic uncertainties. Fig3a.pdf [14 KiB] HiDef png [140 KiB] Thumbnail [108 KiB] *.C file Fig3b.pdf [14 KiB] HiDef png [128 KiB] Thumbnail [105 KiB] *.C file Fig3c.pdf [14 KiB] HiDef png [141 KiB] Thumbnail [124 KiB] *.C file Animated gif made out of all figures. PAPER-2013-029.gif Thumbnail

## Tables and captions

 Systematic uncertainties on the branching fraction ratios of the decays $B ^0 \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} p \overline p$ , $B ^0_ s \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} p \overline p$ and $B ^+ \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} p \overline p \pi ^+$ measured relative to $B ^0_ s \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} \pi ^+ \pi ^-$ . The total is obtained from the sum in quadrature of all contributions. Table_1.pdf [48 KiB] HiDef png [61 KiB] Thumbnail [26 KiB] tex code

Created on 27 February 2021.