# Observation of $B^0\_\_\_(s) \rightarrow J/\psi p\bar{p}$ decays and precision measurements of the $B^0\_\_\_(s)$ masses

Roel Aaij, Carlos Abellán Beteta, Bernardo Adeva, Marco Adinolfi, Christine
Angela Aidala, Ziad Ajaltouni, Simon Akar, Pietro Albicocco, Johannes
Albrecht, Federico Alessio, et al.

► To cite this version:

Roel Aaij, Carlos Abellán Beteta, Bernardo Adeva, Marco Adinolfi, Christine Angela Aidala, et al.. Observation of $B^0\_\_\_(s) \rightarrow J/\psi p\bar{p}$ decays and precision measurements of the $B^0\_\_\_(s)$ masses. Phys.Rev.Lett., 2019, 122 (19), pp.191804. 10.1103/PhysRevLett.122.191804. hal-02284555

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# Observation of $B_{(s)}^0 \to J/\psi p\bar{p}$ decays and precision measurements of the $B_{(s)}^0$ masses

LHCb collaboration†

## Abstract

The first observation of the decays $B_{(s)}^0 \to J/\psi p\bar{p}$ is reported, using proton-proton collision data corresponding to an integrated luminosity of 5.2 fb⁻¹, collected with the LHCb detector. These decays are suppressed due to limited available phase space, as well as due to Okubo-Zweig-Iizuka or Cabibbo suppression. The measured branching fractions are

$$ \mathcal{B}(B^0 \to J/\psi p\bar{p}) = (4.51 \pm 0.40 \text{ (stat)} \pm 0.44 \text{ (syst)}) \times 10^{-7}, $$

$$ \mathcal{B}(B_s^0 \to J/\psi p\bar{p}) = (3.58 \pm 0.19 \text{ (stat)} \pm 0.39 \text{ (syst)}) \times 10^{-6}. $$

For the $B_s^0$ meson, the result is much higher than the expected value of $\mathcal{O}(10^{-9})$. The small available phase space in these decays also allows for the most precise single measurement of both the $B^0$ mass as 5279.74 ± 0.30 (stat) ± 0.10 (syst) MeV, and the $B_s^0$ mass as 5366.85 ± 0.19 (stat) ± 0.13 (syst) MeV.

Published in Phys. Rev. Lett. 122, 191804 (2019)

© 2019 CERN for the benefit of the LHCb collaboration, licence CC-BY-4.0.

<footnote>†Authors are listed at the end of this paper.</footnote>
Multiquark hadronic states beyond the well-studied quark-antiquark (meson) and three-quark (baryon) combinations remain elusive even sixty years after their prediction in the quark model [1,2]. Employing an amplitude analysis of $A_b^0 \to J/\psi pK^-$ decays, the LHCb collaboration has found states consistent with $|uudc\bar{c}\rangle$ pentaquarks decaying to $J/\psi p[3,4]$ (charge conjugation is implied throughout this Letter). The decays $B_{(s)}^0 \to J/\psi p\bar{p}$ are sensitive to pentaquark searches in the $J/\psi p$ and $J/\psi \bar{p}$ components and to glueball states [5,6] in the $p\bar{p}$ system. Baryonic $B_{(s)}^0$ decays are also interesting to study the dynamics of the final baryon-antibaryon system and its characteristic threshold enhancement, whose underlying origin has still to be completely understood [7].

In the leading Feynman diagrams shown in Fig. 1, the $B^0$ mode is Cabibbo suppressed due to the presence of the Cabibbo-Kobayashi-Maskawa element $V_{cd}$, while the $B_s^0$ mode is Okubo-Zweig-Iizuka suppressed [2, 8, 9]. The naïve theoretical expectation for the branching fraction $\mathcal{B}(B_s^0 \to J/\psi p\bar{p})$ is at the level of $10^{-9}$ [10]. However, the presence of an intermediate pentaquark or glueball state can enhance the decay rate. The authors of Ref. [10] pointed out the potential sensitivity of $B_s^0 \to J/\psi p\bar{p}$ decays to tensor glueball states via a possible resonant contribution of $f_J(2220) \to p\bar{p}$, which could enhance the $B_s^0 \to J/\psi p\bar{p}$ decay branching fraction up to order $10^{-6}$. Hints towards such enhancements were noted in a previous LHCb measurement using $1 \text{ fb}^{-1}$ of pp collision data, where no observation for either mode was made, but a 2.8 standard deviation excess was seen for the $B_s^0 \to J/\psi p\bar{p}$ decay [11].

These decays also allow for high-precision mass measurements. The kinetic energies in the $B_{(s)}^0$ rest systems of the decay products (Q-values) are approximately 306 MeV for $B^0$ and 393 MeV for $B_s^0$ decays. The small Q-values imply a very small contribution from momentum uncertainties to the $B_{(s)}^0$ mass measurements.

In this Letter, the first observation of these modes along with their branching fraction and $B^0$ and $B_s^0$ mass measurements are reported employing a data sample corresponding to $5.2 \text{ fb}^{-1}$ of pp collision data collected by the LHCb experiment. As a normalization mode, the copious $B_s^0 \to J/\psi \phi(\to K^+K^-)$ sample is used, which is similar in topology to the signal channels.

The LHCb detector [12, 13] is a single-arm forward spectrometer covering the

<figure><img src="image_3.png" /><figcaption>Figure 1: Leading Feynman diagrams for (a) $B^0 \to J/\psi p\bar{p}$ and (b) $B_s^0 \to J/\psi p\bar{p}$ decays.</figcaption></figure>
pseudorapidity range $2 < \eta < 5$, designed for the study of particles containing b or c quarks. The detector includes a high-precision tracking system consisting of a silicon-strip vertex detector surrounding the pp interaction region [14], a large-area silicon-strip detector located upstream of a dipole magnet with a bending power of about 4 Tm, and three stations of silicon-strip detectors and straw drift tubes [15] placed downstream of the magnet. The tracking system provides a measurement of the momentum, $p$, of charged particles with a relative uncertainty that varies from 0.5% at low momentum to 1.0% at 200 GeV.<fnref n="1" /> Different types of charged hadrons are distinguished using information from two ring-imaging Cherenkov detectors [16]. Muons are identified by a system composed of alternating layers of iron and multiwire proportional chambers [17]. The online event selection is performed by a trigger [18], comprising a hardware stage based on information from the muon system, followed by a software stage that applies a full event reconstruction. The software trigger is a combination of event categories mostly relying on identifying $J/\psi$ decays consistent with a B-meson decay topology with two muon tracks originating from a secondary decay vertex detached from the primary pp collision point.

The pp collision data used in this analysis were collected at center-of-mass energies of 7 and 8 TeV (3 fb⁻<fnref n="1" />) and 13 TeV (2.2 fb⁻<fnref n="1" />), during the Run 1 (2011 and 2012) and Run 2 (2015 and 2016) run periods, respectively. The data taking conditions differ enough between the two run periods, such that they are analyzed separately and the results combined at the end.

Samples of simulated events are used to study the properties of the signal and control channels. The pp collisions are generated using PYTHIA [19] with a specific LHCb configuration [20]. Decays of hadronic particles are described by EVTGEN [21], in which final-state radiation is generated using PHOTOS [22]. For the $B_s^0 \to J/\psi \phi$ mode, simulation samples are generated according to a decay model based on results reported in Ref. [23], while the $B_{(s)}^0 \to J/\psi p\bar{p}$ signal modes are generated uniformly in phase space. The interactions of the generated particles with the detector and its response are implemented using the GEANT4 toolkit [24] as described in Ref. [25].

The event selection relies on the excellent vertexing and charged particle identification (PID) capabilities of the LHCb detector. For a given particle, the associated primary vertex (PV) corresponds to that with the smallest $\chi^2_{\text{IP}}$, defined as the difference in $\chi^2$ between the PV fit including and excluding the particle. Signal candidates are formed starting with a pair of charged tracks, consistent with muons originating from a common vertex significantly displaced from its associated PV and with an invariant mass consistent with the $J/\psi$ meson. Another pair of oppositely charged tracks, identified as protons and originating from a common vertex, is combined with the $J/\psi$ candidate to form a $B_{(s)}^0$ candidate. The entire decay topology is submitted to a kinematic fit where the dimuon invariant mass is constrained to the known $J/\psi$ mass [26]. The $B_s^0 \to J/\psi \phi$ control mode candidates are reconstructed in a similar fashion, replacing the $p\bar{p}$ combination with a pair of charged tracks identified as $K^+K^-$ candidates, required to have an invariant mass within ±5 MeV of the known $\phi$-meson mass [26]. All charged tracks are required to be of good quality and have $p_T > 300$ MeV ($p_T > 550$ MeV) for $p$ or $K$ ($\mu$). For the $B_s^0 \to J/\psi \phi$ mode, the contamination from $B^0 \to J/\psi K^+\pi^-$ decays with a pion misidentified as a kaon is rejected by imposing a $B^0$ mass veto and using PID information. At this stage, the combinatorial background dominates, comprising a correctly reconstructed $J/\psi$ meson

<footnote n="1">¹Natural units with $\hbar = c = 1$ are used throughout.</footnote>
candidate combined with two unrelated charged tracks.

At this stage, a multidimensional gradient-boosting algorithm [27] is used to weight the simulated $B_s^0 \rightarrow J/\psi \phi$ events to match background-subtracted data distributions in all the training variables. These weights are denoted as GB-weights. The background-subtracted data distributions are obtained using the sPlot technique [28]. Under the assumption that the relative corrections between data and simulation are similar among different $B_{(s)}^0 \rightarrow J/\psi h^+ h'^-$ decay topologies, $h^+$ and $h'^-$ being charged hadrons, the GB-weights obtained from the control mode are applied to the signal mode. To validate this assumption, similar GB-weights are derived using another control mode, $B^0 \rightarrow J/\psi K^+ \pi^-$, yielding similar results.

For further background suppression, two multivariate classifiers are applied, each employing a gradient-boosted decision tree (BDT) [29]. In the first stage, the BDT$_{kin}$ classifier, based on kinematical and topological variables of the $B_s^0$ candidate, is trained using the $B_s^0 \rightarrow J/\psi \phi$ decays from simulation as signal proxy, and selected $J/\psi K^+ K^-$ candidates in the mass window [5450, 5700] MeV as background. For BDT$_{kin}$, only kinematic variables whose distributions are similar between the signal and the control mode are employed. These include the $p, p_T$, and $\chi_{IP}^2$ values of the $B_s^0$ meson, the $\chi^2$ probability from a kinematic fit [30] to the decay topology, and the impact parameter (IP) of the muons with respect to the associated PV.

To choose the BDT$_{kin}$ selection cut, the $B_s^0 \rightarrow J/\psi p\bar{p}$ signal figure of merit, $S/\sqrt{S+B}$, is required to exceed five in a $2\sigma$ window around the $B_s^0$ mass peak. The background yield, $B$, is estimated from a fit to the $J/\psi p\bar{p}$ invariant mass distribution. To estimate the expected signal yield, $S$, the central value of the $B_s^0 \rightarrow J/\psi p\bar{p}$ branching fraction quoted in Ref. [11] is used, along with the signal efficiency obtained from simulation.

In the final selection stage, a second classifier, BDT$_{PID}$, uses the hadron PID information from the Cherenkov detector system to distinguish between pions, kaons and protons. Aside from PID, the BDT$_{PID}$ training variables also include the $p, p_T$ and $\chi_{IP}^2$ values of the protons. The signal sample is taken as the $B_s^0 \rightarrow J/\psi p\bar{p}$ simulation incorporating the GB-weights for the kinematic variables, while the background sample is taken from events in data with $m(J/\psi p\bar{p}) \in [5450, 5500]$ MeV. The hadron PID variables in the simulation require further corrections to be representative of data. The PID variables are obtained from high-yield calibration samples of $\Lambda_c^+ \rightarrow pK^-\pi^+$ and $D^{*+} \rightarrow D^0(\rightarrow K^-\pi^+)\pi^+$ decays, which can be selected as a function of the $p, p_T$ and the number of tracks in the event using only kinematic information [31]. The optimal BDT$_{PID}$ selection criterion is chosen by maximizing the figure of merit $S/\sqrt{S+B}$, with the initial signal and background yields obtained from a fit to the $m(J/\psi p\bar{p})$ distribution after the BDT$_{kin}$ selection.

For the $B_s^0 \rightarrow J/\psi \phi$ control mode, the selection is performed using a dedicated classifier, BDT$_{CS}$, which includes the kinematic variables considered in BDT$_{kin}$ with the addition of the PID information.

After application of all selection requirements, the background is predominantly combinatorial. Approximately 1% of the selected events contain more than one candidate at this stage; a single candidate is selected randomly. The efficiency of the trigger, detector acceptance, reconstruction and selection procedure is approximately 1%, as estimated from simulation.

The $B^0$ and $B_s^0$ signal and background yields are determined via an extended maximum likelihood fit to the $J/\psi p\bar{p}$ invariant mass distribution in the range [5220, 5420] MeV. Each signal shape is modeled as the sum of two Crystal Ball [32] functions sharing a
<figure><img src="image_4.png" /><figcaption>Figure 2: Fit to the $J/\psi p\bar{p}$ invariant-mass distribution of the $B_{(s)}^0$ signal modes.</figcaption></figure>

<table><caption>Table 1: Signal yields and masses for $B^0$ and $B_s^0$ mesons.</caption><thead><tr><th>Mode</th><th>Yield</th><th>$B_{(s)}^0$ mass [MeV]</th></tr></thead><tbody><tr><td>$B^0 \to J/\psi p\bar{p}$</td><td>256 ± 22</td><td>5279.74 ± 0.30</td></tr><tr><td>$B_s^0 \to J/\psi p\bar{p}$</td><td>609 ± 31</td><td>5366.85 ± 0.19</td></tr></tbody></table>

common peak position, with tails on either sides of the peak to describe the radiative and misreconstruction effects. The background shape is modeled by a first-order polynomial with parameters determined from the fit to data. The signal-model parameters are determined from simulation and only the $B^0$ and $B_s^0$ central mass values are left as free parameters in the fit to data. The detector invariant-mass resolution is in agreement with simulations within a factor of 1.007 ± 0.004 as determined with the control mode. Residual discrepancies are accounted for in the systematic uncertainties. In order to validate the fit model, 1000 mass spectra are generated according to the model and fitted employing an alternative model comprising three Gaussian components for the signal and an exponential function for background. The difference between the input value of the yields and the mean of the fitted yields from the alternative model is assigned as a systematic uncertainty. The mass fit for the control mode uses a similar $B_s^0$ signal lineshape, with the background modeled by an exponential function. The result of the fit to the combined Run 1 and Run 2 control mode yields a signal of 136,800 ± 400. The corresponding fit to the signal-mode candidates is shown in Fig. 2 with the results reported in Table 1, where clear signals of $B^0$ and $B_s^0$ are observed.
The branching fractions measured with respect to the $B_s^0 \to J/\psi \phi$ control mode are

$$ \frac{\mathcal{B}(B^0 \to J/\psi p\bar{p})}{\mathcal{B}(B_s^0 \to J/\psi \phi) \times \mathcal{B}(\phi \to K^+K^-) \times f_s/f_d} = \frac{N_{B^0 \to J/\psi p\bar{p}}^{\text{corr}}}{N_{B_s^0 \to J/\psi K^+K^-}^{\text{corr}}}, \\ \\ \frac{\mathcal{B}(B_s^0 \to J/\psi p\bar{p})}{\mathcal{B}(B_s^0 \to J/\psi \phi) \times \mathcal{B}(\phi \to K^+K^-)} = \frac{N_{B_s^0 \to J/\psi p\bar{p}}^{\text{corr}}}{N_{B_s^0 \to J/\psi K^+K^-}^{\text{corr}}}, $$

where $f_s/f_d$ is the ratio of the b-quark hadronization probabilities into $B_s^0$ and $B^0$ mesons, and $N^{\text{corr}}$ denotes efficiency-corrected signal yields. For the signal modes, since the physics model is not known a priori, an event-by-event efficiency correction is applied to the data. It is derived from simulation as a function of the kinematic variables, which are given in detail in the Appendix.

Since the control mode has a topology very similar to that of the signal mode, most of the systematic uncertainties cancel in the branching-fraction ratio measurement. Residual systematic effects of the PID efficiency estimation are due to the correction procedure. An alternative PID correction is considered using proton calibration samples from decays of the long-lived $\Lambda$ baryon to a proton and a pion, instead of prompt $\Lambda_c^+$ decays. The difference between the two methods is assigned as a systematic uncertainty. The degree to which the simulation describes hadronic interactions with the detector material is less accurate for baryons than it is for mesons [21]. Following Ref. [33], a systematic uncertainty of 4% (1.1%) per proton (kaon) is assigned. Other systematic effects include the choice of the fit model, the weighting procedure, the trigger efficiency, and the presence of events with more than one candidate. The overall systematic uncertainties on the ratio of branching fractions are 7.2% (7.2%) and 6.5% (6.6%) for $B_s^0$ ($B^0$) meson in Run 1 and Run 2, respectively, where the relevant contributions, listed in Table 2, are added in quadrature. Since the detector and the analysis methods remain the same between the two run periods, the systematic uncertainties are fully correlated while the statistical uncertainties are uncorrelated. The combination of the measurements is taken as a weighted mean to give the branching fraction ratios

$$ \frac{\mathcal{B}(B^0 \to J/\psi p\bar{p})}{\mathcal{B}(B_s^0 \to J/\psi \phi) \times \mathcal{B}(\phi \to K^+K^-) \times f_s/f_d} = (0.329 \pm 0.029 \text{ (stat)} \pm 0.022 \text{ (syst)}) \times 10^{-2}, \\ \\ \frac{\mathcal{B}(B_s^0 \to J/\psi p\bar{p})}{\mathcal{B}(B_s^0 \to J/\psi \phi) \times \mathcal{B}(\phi \to K^+K^-)} = (0.706 \pm 0.037 \text{ (stat)} \pm 0.048 \text{ (syst)}) \times 10^{-2}, $$

where the first uncertainty is statistical and the second is systematic. For the absolute branching-fraction determination, the value $\mathcal{B}(B_s^0 \to J/\psi \phi) \times \mathcal{B}(\phi \to K^+K^-) \times f_s/f_d = (1.314 \pm 0.016 \pm 0.079) \times 10^{-4}$ is obtained from Ref. [34] as the product of the two branching ratios, $\mathcal{B}(B_s^0 \to J/\psi \phi) = (10.50 \pm 0.13 \pm 0.64) \times 10^{-4}$ and $\mathcal{B}(\phi \to K^+K^-) = 0.489 \pm 0.005$, and the ratio of fragmentation probabilities $f_s/f_d = 0.256 \pm 0.020$ [35]. For the $B_s^0$-meson normalization, the updated ratio $f_s/f_d = 0.259 \pm 0.015$ [35] is used in Run 1, while for Run 2 it has been multiplied by an additional scale factor of $1.068 \pm 0.046$ [36] to take into account the dependence on the center of mass energy. The small S-wave $K^+K^-$ fraction under the $\phi(1020)$ resonance, $F_S = 0.0070 \pm 0.0005$ [34], is accounted for as a correction. The absolute branching fractions are then combined to give

$$ \mathcal{B}(B^0 \to J/\psi p\bar{p}) = (4.51 \pm 0.40 \text{ (stat)} \pm 0.44 \text{ (syst)}) \times 10^{-7}, \\ \\ \mathcal{B}(B_s^0 \to J/\psi p\bar{p}) = (3.58 \pm 0.19 \text{ (stat)} \pm 0.39 \text{ (syst)}) \times 10^{-6}, $$
<table><caption>Table 2: Systematic uncertainties on the branching fraction measurements for Run 1 and Run 2. The total uncertainties on the branching fraction ratios (BFR) are the sum of the systematic uncertainties, added in quadrature. The total uncertainties on the absolute branching fractions (B) include the normalization and the uncertainties on the ratio $f_s/f_d$ from external measurements as well.</caption><thead><tr><th></th><th>B(B<sup>0</sup> → J/ψp<span style="text-decoration: overline">p</span>)</th><th>B(B<sub>s</sub><sup>0</sup> → J/ψp<span style="text-decoration: overline">p</span>)</th></tr><tr><th></th><th>Run 1 (Run 2)</th><th>Run 1 (Run 2)</th></tr></thead><tbody><tr><td>Fit model</td><td>1.0 (0.5)%</td><td>1.0 (0.9)%</td></tr><tr><td>Detector resolution</td><td>0.6 (0.5)%</td><td>0.4 (0.6)%</td></tr><tr><td>PID efficiency</td><td>5.0 (4.0)%</td><td>5.0 (4.0)%</td></tr><tr><td>Trigger</td><td>1.0 (1.0)%</td><td>1.0 (1.0)%</td></tr><tr><td>Tracking</td><td>5.0 (5.0)%</td><td>5.0 (5.0)%</td></tr><tr><td>Simulation weighting</td><td>0.4 (0.4)%</td><td>0.3 (0.3)%</td></tr><tr><td>Multiple candidates</td><td>0.1 (0.1)%</td><td>0.1 (0.1)%</td></tr><tr><td>Total on BFR</td><td>7.2 (6.5)%</td><td>7.2 (6.6)%</td></tr><tr><td>Normalization</td><td>6.1 (6.1)%</td><td>6.1 (6.1)%</td></tr><tr><td>f<sub>s</sub>/f<sub>d</sub></td><td>— (4.3)%</td><td>5.8 (5.8)%</td></tr><tr><td>Total on B</td><td>9.4 (10.1)%</td><td>11.1 (10.7)%</td></tr></tbody></table>

where the systematic uncertainty is the sum in quadrature of the overall systematic contribution on the ratio of branching fractions, the normalization mode uncertainty and the $f_s/f_d$ uncertainty for the $B_s^0$ signal. Table 2 summarizes the systematic uncertainties separately for the run periods. The dominant contributions are the normalization, the PID, and the tracking systematic uncertainties. For the $B^0$ meson, the external normalization measurement from Run 1, $B(B_s^0 \to J/\psi\phi) \times B(\phi \to K^+K^-) \times f_s/f_d$ [34] is used, while for Run 2 the additional energy-dependent correction on $f_s/f_d$ has an uncertainty of 4.3%. For the $B_s^0$ meson, the measured $B(B_s^0 \to J/\psi\phi) \times B(\phi \to K^+K^-) \times f_s/f_d$ is divided by $f_s/f_d$ to obtain the $B_s^0$ normalization, $B(B_s^0 \to J/\psi\phi) \times B(\phi \to K^+K^-)$, resulting in an uncertainty on $f_s/f_d$ independent of the run condition.

In addition, the small Q-values of the $B_{(s)}^0 \to J/\psi p\bar{p}$ decays also allow for precise measurements of the $B^0$ and $B_s^0$ masses, with a resolution of 3.3 MeV (3.8 MeV) for the $B^0$ ($B_s^0$) meson. The sources of systematic uncertainties include momentum scaling due to imperfections in the magnetic-field mapping derived using well-known narrow resonances, uncertainties on particle interactions with the detector material, and the choice of the

<table><caption>Table 3: Systematic uncertainties of $B^0$ and $B_s^0$ mass measurements.</caption><thead><tr><th></th><th>B<sup>0</sup></th><th>B<sub>s</sub><sup>0</sup></th></tr><tr><th></th><th>[MeV]</th><th>[MeV]</th></tr></thead><tbody><tr><td>Momentum scale</td><td>0.097</td><td>0.124</td></tr><tr><td>Mass fit model</td><td>0.020</td><td>0.020</td></tr><tr><td>Energy loss correction</td><td>0.030</td><td>0.030</td></tr><tr><td>Total</td><td>0.103</td><td>0.129</td></tr></tbody></table>
signal model, as reported in Table 3. The uncertainty on the proton mass is neglected. The final results are

$$m_{B^0} = 5279.74 \pm 0.30 \text{ (stat)} \pm 0.10 \text{ (syst)} \text{ MeV},$$

$$m_{B_s^0} = 5366.85 \pm 0.19 \text{ (stat)} \pm 0.13 \text{ (syst)} \text{ MeV},$$

with a correlation of $4 \times 10^{-4}$ in the statistical uncertainty. These represent the most precise single measurements for the $B^0$ and $B_s^0$ masses.

In summary, the first observation of the $B^0 \to J/\psi p\bar{p}$ and $B_s^0 \to J/\psi p\bar{p}$ decays is reported. The measured branching fraction for the $B^0 \to J/\psi p\bar{p}$ decay is consistent with theoretical expectations [10] while that for $B_s^0 \to J/\psi p\bar{p}$ is enhanced by two orders of magnitude with respect to predictions without resonant contributions [10]. More data are needed for glueball and pentaquark searches through a full Dalitz plot analysis. The world's best single measurements of the $B^0$ and $B_s^0$ masses are also reported.

## Acknowledgements

We express our gratitude to our colleagues in the CERN accelerator departments for the excellent performance of the LHC. We thank the technical and administrative staff at the LHCb institutes. We acknowledge support from CERN and from the national agencies: CAPES, CNPq, FAPERJ and FINEP (Brazil); MOST and NSFC (China); CNRS/IN2P3 (France); BMBF, DFG and MPG (Germany); INFN (Italy); NWO (Netherlands); MNiSW and NCN (Poland); MEN/IFA (Romania); MSHE (Russia); MinECo (Spain); SNSF and SER (Switzerland); NASU (Ukraine); STFC (United Kingdom); NSF (USA). We acknowledge the computing resources that are provided by CERN, IN2P3 (France), KIT and DESY (Germany), INFN (Italy), SURF (Netherlands), PIC (Spain), GridPP (United Kingdom), RRCKI and Yandex LLC (Russia), CSCS (Switzerland), IFIN-HH (Romania), CBPF (Brazil), (France), KIT and DESY (Germany), INFN (Italy), SURF (Netherlands), PIC (Spain), GridPP (United Kingdom), RRCKI and Yandex LLC (Russia), CSCS (Switzerland), IFIN-HH (Romania), CBPF (Brazil), PL-GRID (Poland) and OSC (USA). We are indebted to the communities behind the multiple open-source software packages on which we depend. Individual groups or members have received support from Fondazione Fratelli Confalonieri (Italy), AvH Foundation (Germany); EPLANET, Marie Skłodowska-Curie Actions and ERC (European Union); ANR, Labex P2IO and OCEVU, and Région Auvergne-Rhône-Alpes (France); Key Research Program of Frontier Sciences of CAS, CAS PIFI, and the Thousand Talents Program (China); RFBR, RSF and Yandex LLC (Russia); GVA, XuntaGal and GENCAT (Spain); the Royal Society and the Leverhulme Trust (United Kingdom); Laboratory Directed Research and Development program of LANL (USA).
# Appendix

## A. Efficiency parameterization for the signal mode

<figure><img src="image_5.png" /><figcaption>Figure 3: The three angular variables {$\theta_{\ell}, \theta_{h}, \chi$} for the decay $B \to J/\psi (\to \mu^{+}\mu^{-})h^{+}h^{-}$, where $h \in \{p, K\}$. The dihadron (in red) and dilepton (in blue) coordinate systems lie back-to-back with a common vertical $\hat{y}$ axis. The angle between the decay planes is $\chi \in (-\pi, \pi]$, while the two helicity angles, $\theta_{h}$ and $\theta_{\ell}$, are defined in the dihadron and dilepton rest frames, respectively.</figcaption></figure>

The 4-body phase-space of the decay $B \to J/\psi (\to \mu^{+}\mu^{-})h^{+}h^{-}$, where $h \in \{p, K\}$, is fully described by four independent kinematic variables. One of them is the dihadron invariant mass $m_{h+h^{-}}$. For a given $m_{h+h^{-}}$, the topology can be described by three angles, shown in Fig. 3:

* $\theta_{\ell}$ and $\theta_{h}$: the helicity angles defined in the dimuon and dihadron rest frames, respectively;

* $\chi$: the azimuthal angle between the two decay planes of the dilepton and dihadron systems.

Since the final state is self-conjugate, the $h^{-}$ and the $\mu^{-}$ particles are chosen to define the angles, for both $B_{(s)}^{0}$ and $\bar{B}_{(s)}^{0}$ mesons. For the signal mode, the overall efficiency, including trigger, detector acceptance and selection procedure, is obtained from simulation as a function of the four kinematic variables, $\vec{\phi} \equiv \{m'_{\bar{p}\bar{p}}, \cos\theta_{\ell}, \cos\theta_{h}, \chi'\}$. Here, $m'_{\bar{p}\bar{p}}$ and $\chi'$ are normalized such that all four variables in $\vec{\phi}$ lie in the range $(-1, 1]$. The efficiency is parameterized as the product of Legendre polynomials

$$ \varepsilon(\vec{\phi}) = \sum_{i,j,k,l} c_{i,j,k,l} P(\cos\theta_{\ell}, i)P(\cos\theta_{h}, j)P(\chi', k)P(m'_{\bar{p}\bar{p}}, l), $$

where $P(x, n)$ is a Legendre polynomial of order $n$ in $x \in (-1, 1]$. Employing the maximum order of the polynomials as $\{3, 7, 7, 5\}$ for $\{m'_{\bar{p}\bar{p}}, \cos\theta_{\ell}, \cos\theta_{h}, \chi'\}$, respectively, was found to give a good parameterization. Simulation samples are employed, where $B_{(s)}^{0} \to J/\psi p\bar{p}$ events are generated uniformly in phase space. The coefficients, $c_{i,j,k,l}$, are determined
from the simulation using a moments technique employing the orthogonality of Legendre polynomials

$$c_{i,j,k,l} = C \sum_{n=0}^{N_{\text{recon}}} \left(\frac{2i+1}{2}\right) \left(\frac{2j+1}{2}\right) \left(\frac{2k+1}{2}\right) \left(\frac{2l+1}{2}\right) \times P(\cos \theta_l, i) P(\cos \theta_h, j) P(\chi', k) P(m'_{p\bar{p}}, l).$$

The sum is over the number of reconstructed decays, $N_{\text{recon}}$, in the simulation sample after all selection criteria. The prefactor $C$ ensures appropriate normalization. For a given data candidate, the corresponding kinematic variables, $\vec{\phi}$, are reconstructed and the efficiency, $\epsilon(\vec{\phi})$, is computed according to the parameterization. The candidate is subsequently assigned a weight, $1/\epsilon(\vec{\phi})$, to account for the detector efficiency.

## B. Combining the Run 1 and Run 2 branching fraction results

The ratio of branching fractions for Run 1 and Run 2 are provided here separately. For Run 1,

$$\frac{\mathcal{B}(B^0 \rightarrow J/\psi p\bar{p})}{\mathcal{B}(B_s^0 \rightarrow J/\psi \phi) \times \mathcal{B}(\phi \rightarrow K^+K^-) \times f_s/f_d} = (0.35 \pm 0.05(\text{stat}) \pm 0.02(\text{syst})) \times 10^{-2},$$ $$\frac{\mathcal{B}(B_s^0 \rightarrow J/\psi p\bar{p})}{\mathcal{B}(B_s^0 \rightarrow J/\psi \phi) \times \mathcal{B}(\phi \rightarrow K^+K^-)} = (0.68 \pm 0.06(\text{stat}) \pm 0.05(\text{syst})) \times 10^{-2},$$

while for Run 2,

$$\frac{\mathcal{B}(B^0 \rightarrow J/\psi p\bar{p})}{\mathcal{B}(B_s^0 \rightarrow J/\psi \phi) \times \mathcal{B}(\phi \rightarrow K^+K^-) \times f_s/f_d} = (0.32 \pm 0.04(\text{stat}) \pm 0.02(\text{syst})) \times 10^{-2}.$$ $$\frac{\mathcal{B}(B_s^0 \rightarrow J/\psi p\bar{p})}{\mathcal{B}(B_s^0 \rightarrow J/\psi \phi) \times \mathcal{B}(\phi \rightarrow K^+K^-)} = (0.72 \pm 0.05(\text{stat}) \pm 0.05(\text{syst})) \times 10^{-2}.$$

The absolute branching fractions obtained from our present knowledge of $\mathcal{B}(B_s^0 \rightarrow J/\psi \phi) \times \mathcal{B}(\phi \rightarrow K^+K^-) \times f_s/f_d = (1.314 \pm 0.016 \pm 0.079) \times 10^{-4}$ and $f_s/f_d = 0.259 \pm 0.015$ are, for Run 1,

$$\mathcal{B}(B^0 \rightarrow J/\psi p\bar{p}) = (4.54 \pm 0.62(\text{stat}) \pm 0.33(\text{syst}) \pm 0.28(\text{norm})) \times 10^{-7},$$ $$\mathcal{B}(B_s^0 \rightarrow J/\psi p\bar{p}) = (3.45 \pm 0.31(\text{stat}) \pm 0.25(\text{syst}) \pm 0.21(\text{norm}) \pm 0.20(f_s/f_d)) \times 10^{-6},$$

and for Run 2,

$$\mathcal{B}(B^0 \rightarrow J/\psi p\bar{p}) = (4.49 \pm 0.52(\text{stat}) \pm 0.29(\text{syst}) \pm 0.28(\text{norm}) \pm 0.19(f_s/f_d)) \times 10^{-7},$$ $$\mathcal{B}(B_s^0 \rightarrow J/\psi p\bar{p}) = (3.66 \pm 0.25(\text{stat}) \pm 0.24(\text{syst}) \pm 0.22(\text{norm}) \pm 0.21(f_s/f_d)) \times 10^{-6}.$$

To combine the results from the Run 1 and Run 2 data samples, the systematic uncertainties are taken as fully correlated between the run periods, since the data are collected employing the same detector and analysis techniques. The statistical uncertainties are considered uncorrelated since the datasets are disjoint. The covariance matrices are constructed as

$$V = \begin{pmatrix} \sigma_{\text{stat, Run 1}}^2 + \sigma_{\text{syst, Run 1}}^2 & \sigma_{\text{syst, Run 1}} \times \sigma_{\text{syst, Run 2}} \\ \sigma_{\text{syst, Run 1}} \times \sigma_{\text{syst, Run 2}} & \sigma_{\text{syst, Run 2}}^2 + \sigma_{\text{syst, Run 2}}^2 \end{pmatrix},$$
with the numerical values for the absolute branching fraction combination as

$$V_{B^0} = \begin{pmatrix} 0.5667 & 0.1916 \\ 0.1916 & 0.4722 \end{pmatrix} \times 10^{-14},$$

$$V_{B_s^0} = \begin{pmatrix} 0.2401 & 0.1502 \\ 0.1502 & 0.2142 \end{pmatrix} \times 10^{-12}.$$

The weighted mean value and uncertainty are then calculated as

$$\bar{x} = \sum_{i \in \{1,2\}} w_i x_i,$$

$$\sigma_x^2 = \sum_{i,k \in \{1,2\}} w_i w_k V_{ik},$$

respectively, where the variable $x$ denotes the branching fraction and the weights are obtained from the inverse of the aforementioned covariance matrix as

$$w_i = \frac{\sum_{k \in \{1,2\}} (V^{-1})_{ik}}{\sum_{j,k \in \{1,2\}} (V^{-1})_{jk}}.$$

## References

[1] M. Gell-Mann, *A schematic model of baryons and mesons*, Phys. Lett. **8** (1964) 214.

[2] G. Zweig, *An $SU_3$ model for strong interaction symmetry and its breaking*, Tech. Rep. CERN-TH-401, CERN, Geneva, Jan. 1964.

[3] LHCb collaboration, R. Aaij et al., *Observation of $J/\psi p$ resonances consistent with pentaquark states in $\Lambda_b^0 \to J/\psi pK^-$ decays*, Phys. Rev. Lett. **115** (2015) 072001, arXiv:1507.03414.

[4] LHCb collaboration, R. Aaij et al., *Model-independent evidence for $J/\psi p$ contributions to $\Lambda_b^0 \to J/\psi pK^-$ decays*, Phys. Rev. Lett. **117** (2016) 082002, arXiv:1604.05708.

[5] C. J. Morningstar and M. Peardon, *Glueball spectrum from an anisotropic lattice study*, Phys. Rev. **D60** (1999) 034509, arXiv:hep-lat/9901004.

[6] Y. Chen et al., *Glueball spectrum and matrix elements on anisotropic lattices*, Phys. Rev. **D73** (2006) 014516, arXiv:hep-lat/0510074.

[7] J. L. Rosner, *Low-mass baryon-antibaryon enhancements in $B$ decays*, Phys. Rev. **D68** (2003) 014004, arXiv:hep-ph/0303079.

[8] S. Okubo, *$\phi$-meson and unitary symmetry model*, Phys. Lett. **5** (1963) 165.
[9] J. Iizuka, *A systematics and phenomenology of meson family*, Prog. Theor. Phys. Suppl. **37** (1966) 21.

[10] Y. K. Hsiao and C. Q. Geng, $f_J(2220)$ and hadronic $\bar{B}_s^0$ decays, Eur. Phys. J. C75 (2015) 101, arXiv:1412.4900.

[11] LHCb collaboration, R. Aaij et al., *Searches for $B_{(s)}^0 \to J/\psi p\bar{p}$ and $B^+ \to J/\psi p\bar{p}\pi^+$ decays*, JHEP **09** (2013) 006, arXiv:1306.4489.

[12] LHCb collaboration, A. A. Alves Jr. et al., *The LHCb detector at the LHC*, JINST **3** (2008) S08005.

[13] LHCb collaboration, R. Aaij et al., *LHCb detector performance*, Int. J. Mod. Phys. **A30** (2015) 1530022, arXiv:1412.6352.

[14] R. Aaij et al., *Performance of the LHCb Vertex Locator*, JINST **9** (2014) P09007, arXiv:1405.7808.

[15] R. Arink et al., *Performance of the LHCb Outer Tracker*, JINST **9** (2014) P01002, arXiv:1311.3893.

[16] M. Adinolfi et al., *Performance of the LHCb RICH detector at the LHC*, Eur. Phys. J. **C73** (2013) 2431, arXiv:1211.6759.

[17] A. A. Alves Jr. et al., *Performance of the LHCb muon system*, JINST **8** (2013) P02022, arXiv:1211.1346.

[18] R. Aaij et al., *The LHCb trigger and its performance in 2011*, JINST **8** (2013) P04022, arXiv:1211.3055.

[19] T. Sjöstrand, S. Mrenna, and P. Skands, *PYTHIA 6.4 physics and manual*, JHEP **05** (2006) 026, arXiv:hep-ph/0603175; T. Sjöstrand, S. Mrenna, and P. Skands, *A brief introduction to PYTHIA 8.1*, Comput. Phys. Commun. **178** (2008) 852, arXiv:0710.3820.

[20] I. Belyaev et al., *Handling of the generation of primary events in Gauss, the LHCb simulation framework*, J. Phys. Conf. Ser. **331** (2011) 032047.

[21] D. J. Lange, *The EvtGen particle decay simulation package*, Nucl. Instrum. Meth. **A462** (2001) 152.

[22] P. Golonka and Z. Was, *PHOTOS Monte Carlo: A precision tool for QED corrections in Z and W decays*, Eur. Phys. J. **C45** (2006) 97, arXiv:hep-ph/0506026.

[23] LHCb collaboration, R. Aaij et al., *Precision measurement of CP violation in $B_s^0 \to J/\psi K^+K^-$ decays*, Phys. Rev. Lett. **114** (2015) 041801, arXiv:1411.3104.

[24] Geant4 collaboration, J. Allison et al., *Geant4 developments and applications*, IEEE Trans. Nucl. Sci. **53** (2006) 270; Geant4 collaboration, S. Agostinelli et al., *Geant4: A simulation toolkit*, Nucl. Instrum. Meth. **A506** (2003) 250.
[25] M. Clemencic et al., *The LHCb simulation application, Gauss: Design, evolution and experience*, J. Phys. Conf. Ser. **331** (2011) 032023.

[26] Particle Data Group, M. Tanabashi et al., *Review of particle physics*, Phys. Rev. **D98** (2018) 030001.

[27] A. Rogozhnikov, *Reweighting with Boosted Decision Trees*, J. Phys. Conf. Ser. **762** (2016) 012036, arXiv:1608.05806.

[28] M. Pivk and F. R. Le Diberder, *sPlot: A statistical tool to unfold data distributions*, Nucl. Instrum. Meth. **A555** (2005) 356, arXiv:physics/0402083.

[29] L. Breiman, J. H. Friedman, R. A. Olshen, and C. J. Stone, *Classification and regression trees*, Wadsworth international group, Belmont, California, USA, 1984.

[30] W. D. Hulsbergen, *Decay chain fitting with a Kalman filter*, Nucl. Instrum. Meth. **A552** (2005) 566, arXiv:physics/0503191.

[31] R. Aaij et al., *Selection and processing of calibration samples to measure the particle identification performance of the LHCb experiment in Run 2*, arXiv:1803.00824.

[32] T. Skwarnicki, *A study of the radiative cascade transitions between the Upsilon-prime and Upsilon resonances*, PhD thesis, Institute of Nuclear Physics, Krakow, 1986, DESY-F31-86-02.

[33] LHCb collaboration, R. Aaij et al., *Evidence for the two-body charmless baryonic decay $B^+ \to p\bar{\Lambda}$*, JHEP **04** (2017) 162, arXiv:1611.07805.

[34] LHCb collaboration, R. Aaij et al., *Amplitude analysis and branching fraction measurement of $\bar{B}_s^0 \to J/\psi K^+K^-$*, Phys. Rev. **D87** (2013) 072004, arXiv:1302.1213.

[35] LHCb collaboration, R. Aaij et al., *Measurement of the fragmentation fraction ratio $f_s/f_d$ and its dependence on B meson kinematics*, JHEP **04** (2013) 001, arXiv:1301.5286, $f_s/f_d$ value updated in LHCb-CONF-2013-011.

[36] LHCb collaboration, R. Aaij et al., *Measurement of the $B_s^0 \to \mu^+\mu^-$ branching fraction and effective lifetime and search for $B^0 \to \mu^+\mu^-$ decays*, Phys. Rev. Lett. **118** (2017) 191801, arXiv:1703.05747.
LHCb Collaboration

R. Aaij<sup>29</sup>, C. Abellán Beteta<sup>46</sup>, B. Adeva<sup>43</sup>, M. Adinolfi<sup>50</sup>, C.A. Aidala<sup>77</sup>, Z. Ajaltouni<sup>7</sup>,
S. Akar<sup>61</sup>, P. Albicocco<sup>20</sup>, J. Albrecht<sup>12</sup>, F. Alessio<sup>44</sup>, M. Alexander<sup>55</sup>, A. Alfonso Albero<sup>42</sup>,
G. Alkhazov<sup>35</sup>, P. Alvarez Cartelle<sup>57</sup>, A.A. Alves Jr<sup>43</sup>, S. Amato<sup>2</sup>, S. Amerio<sup>25</sup>, Y. Amhis<sup>9</sup>,
L. An<sup>19</sup>, L. Anderlini<sup>19</sup>, G. Andreassi<sup>45</sup>, M. Andreotti<sup>18</sup>, J.E. Andrews<sup>62</sup>, F. Archilli<sup>29</sup>,
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B. Audurier<sup>24</sup>, S. Bachmann<sup>14</sup>, J.J. Back<sup>52</sup>, S. Baker<sup>57</sup>, V. Balagura<sup>9,b</sup>, W. Baldini<sup>18</sup>,
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F. Baryshnikov<sup>73</sup>, V. Batozskaya<sup>33</sup>, B. Batsukh<sup>63</sup>, A. Battig<sup>12</sup>, V. Battista<sup>45</sup>, A. Bay<sup>45</sup>,
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V. Bellee<sup>45</sup>, N. Belloli<sup>22,i</sup>, K. Belous<sup>41</sup>, I. Belyaev<sup>36</sup>, G. Bencivenni<sup>20</sup>, E. Ben-Haim<sup>10</sup>,
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J. Bhom<sup>31</sup>, M.S. Bieker<sup>12</sup>, S. Bifani<sup>49</sup>, P. Billoir<sup>10</sup>, A. Birnkraut<sup>12</sup>, A. Bizzeti<sup>19,u</sup>, M. Bjørn<sup>59</sup>,
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T. Boettcher<sup>60</sup>, A. Bondar<sup>40,x</sup>, N. Bondar<sup>35</sup>, S. Borghi<sup>58,44</sup>, M. Borisyak<sup>39</sup>, M. Borsato<sup>43</sup>,
M. Boubdir<sup>11</sup>, T.J.V. Bowcock<sup>56</sup>, C. Bozzi<sup>18,44</sup>, S. Braun<sup>14</sup>, M. Brodski<sup>44</sup>, J. Brodzicka<sup>31</sup>,
A. Brossa Gonzalo<sup>52</sup>, D. Brundu<sup>24,44</sup>, E. Buchanan<sup>50</sup>, A. Buonaura<sup>46</sup>, C. Burr<sup>58</sup>, A. Bursche<sup>24</sup>,
J. Buytaert<sup>44</sup>, W. Byczynski<sup>44</sup>, S. Cadeddu<sup>24</sup>, H. Cai<sup>67</sup>, R. Calabrese<sup>18,g</sup>, R. Calladine<sup>49</sup>,
M. Calvi<sup>22,i</sup>, M. Calvo Gomez<sup>42,m</sup>, A. Camboni<sup>42,m</sup>, P. Campana<sup>20</sup>, D.H. Campora Perez<sup>44</sup>,
L. Capriotti<sup>17,e</sup>, A. Carbone<sup>17,e</sup>, G. Carboni<sup>27</sup>, R. Cardinale<sup>21</sup>, A. Cardini<sup>24</sup>, P. Carniti<sup>22,i</sup>,
K. Carvalho Akiba<sup>2</sup>, G. Casse<sup>56</sup>, M. Cattaneo<sup>44</sup>, G. Cavallero<sup>21</sup>, R. Cenci<sup>26,p</sup>, D. Chamont<sup>9</sup>,
M.G. Chapman<sup>50</sup>, M. Charles<sup>10</sup>, Ph. Charpentier<sup>44</sup>, G. Chatzikonstantinidis<sup>49</sup>, M. Chefdeville<sup>6</sup>,
V. Chekalina<sup>39</sup>, C. Chen<sup>3</sup>, S. Chen<sup>24</sup>, S.-G. Chitic<sup>44</sup>, V. Chobanova<sup>43</sup>, M. Chrzaszcz<sup>44</sup>,
A. Chubykin<sup>35</sup>, P. Ciambrone<sup>20</sup>, X. Cid Vidal<sup>43</sup>, G. Ciezarek<sup>44</sup>, F. Cindolo<sup>17</sup>, P.E.L. Clarke<sup>54</sup>,
M. Clemencic<sup>44</sup>, H.V. Cliff<sup>51</sup>, J. Closier<sup>44</sup>, V. Coco<sup>44</sup>, J.A.B. Coelho<sup>9</sup>, J. Cogan<sup>8</sup>, E. Cogneras<sup>7</sup>,
L. Cojocariu<sup>34</sup>, P. Collins<sup>44</sup>, T. Colombo<sup>44</sup>, A. Comerma-Montells<sup>14</sup>, A. Contu<sup>24</sup>, G. Coombs<sup>44</sup>,
S. Coquereau<sup>42</sup>, G. Corti<sup>44</sup>, M. Corvo<sup>18,g</sup>, C.M. Costa Sobral<sup>52</sup>, B. Couturier<sup>44</sup>, G.A. Cowan<sup>54</sup>,
D.C. Craik<sup>60</sup>, A. Crocombe<sup>52</sup>, M. Cruz Torres<sup>1</sup>, R. Currie<sup>54</sup>, F. Da Cunha Marinho<sup>2</sup>,
C.L. Da Silva<sup>78</sup>, E. Dall'Occo<sup>29</sup>, J. Dalseno<sup>43,v</sup>, C. D'Ambrosio<sup>44</sup>, A. Danilina<sup>36</sup>, P. d'Argent<sup>14</sup>,
A. Davis<sup>58</sup>, O. De Aguiar Francisco<sup>44</sup>, K. De Bruyn<sup>44</sup>, S. De Capua<sup>58</sup>, M. De Cian<sup>45</sup>,
J.M. De Miranda<sup>1</sup>, L. De Paula<sup>2</sup>, M. De Serio<sup>16,d</sup>, P. De Simone<sup>20</sup>, J.A. de Vries<sup>29</sup>, C.T. Dean<sup>55</sup>,
W. Dean<sup>77</sup>, D. Decamp<sup>6</sup>, L. Del Buono<sup>10</sup>, B. Delaney<sup>51</sup>, H.-P. Dembinski<sup>13</sup>, M. Demmer<sup>12</sup>,
A. Dendek<sup>32</sup>, D. Derkach<sup>74</sup>, O. Deschamps<sup>7</sup>, F. Desse<sup>9</sup>, F. Dettori<sup>56</sup>, B. Dey<sup>68</sup>, A. Di Canto<sup>44</sup>,
P. Di Nezza<sup>20</sup>, S. Didenko<sup>73</sup>, H. Dijkstra<sup>44</sup>, F. Dordei<sup>24</sup>, M. Dorigo<sup>44,y</sup>, A.C. dos Reis<sup>1</sup>,
A. Dosil Suárez<sup>43</sup>, L. Douglas<sup>55</sup>, A. Dovbnya<sup>47</sup>, K. Dreimanis<sup>56</sup>, L. Dufour<sup>29</sup>, G. Dujany<sup>10</sup>,
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A. Dzyuba<sup>35</sup>, S. Easo<sup>53</sup>, U. Egede<sup>57</sup>, V. Egorychev<sup>36</sup>, S. Eidelman<sup>40,x</sup>, S. Eisenhardt<sup>54</sup>,
U. Eitschberger<sup>12</sup>, R. Ekelhof<sup>12</sup>, L. Eklund<sup>55</sup>, S. Ely<sup>63</sup>, A. Ene<sup>34</sup>, S. Escher<sup>11</sup>, S. Esen<sup>29</sup>,
T. Evans<sup>61</sup>, A. Falabella<sup>17</sup>, C. Färber<sup>44</sup>, N. Farley<sup>49</sup>, S. Farry<sup>56</sup>, D. Fazzini<sup>22,44,i</sup>, M. Féo<sup>44</sup>,
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C. Fitzpatrick<sup>45</sup>, T. Fiutowski<sup>32</sup>, F. Fleuret<sup>9,b</sup>, M. Fontana<sup>44</sup>, F. Fontanelli<sup>21,h</sup>, R. Forty<sup>44</sup>,
V. Franco Lima<sup>56</sup>, M. Frank<sup>44</sup>, C. Frei<sup>44</sup>, J. Fu<sup>23,q</sup>, W. Funk<sup>44</sup>, E. Gabriel<sup>54</sup>,
A. Gallas Torreira<sup>43</sup>, D. Galli<sup>17,e</sup>, S. Gallorini<sup>25</sup>, S. Gambetta<sup>54</sup>, Y. Gan<sup>3</sup>, M. Gandelman<sup>2</sup>,
P. Gandini<sup>23</sup>, Y. Gao<sup>3</sup>, L.M. Garcia Martin<sup>76</sup>, J. García Pardiñas<sup>46</sup>, B. Garcia Plana<sup>43</sup>,
J. Garra Tico<sup>51</sup>, L. Garrido<sup>42</sup>, D. Gascon<sup>42</sup>, C. Gaspar<sup>44</sup>, L. Gavardi<sup>12</sup>, G. Gazzoni<sup>7</sup>,
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V. Gibson<sup>51</sup>, O.G. Girard<sup>45</sup>, P. Gironella Gironell<sup>42</sup>, L. Giubega<sup>34</sup>, K. Gizdov<sup>54</sup>,
V.V. Gligorov¹⁰, C. Göbel⁶⁵, D. Golubkov³⁶, A. Golutvin⁵⁷,⁷³, A. Gomes¹,ᵃ, I.V. Gorelov³⁷,
C. Gotti²²,ᵢ, E. Govorkova²⁹, J.P. Grabowski¹⁴, R. Graciani Diaz⁴², L.A. Granado Cardoso⁴⁴,
E. Graugés⁴², E. Graverini⁴⁶, G. Graziani¹⁹, A. Grecu³⁴, R. Greim²⁹, P. Griffith²⁴, L. Grillo⁵⁸,
L. Gruber⁴⁴, B.R. Gruberg Cazon⁵⁹, O. Grünberg⁷⁰, C. Gu³, E. Gushchin³⁸, A. Guth¹¹,
Yu. Guz⁴¹,⁴⁴, T. Gys⁴⁴, T. Hadavizadeh⁵⁹, C. Hadjivasiliou⁷, G. Haefeli⁴⁵, C. Haen⁴⁴,
S.C. Haines⁵¹, B. Hamilton⁶², X. Han¹⁴, T.H. Hancock⁵⁹, S. Hansmann-Menzemer¹⁴,
N. Harnew⁵⁹, T. Harrison⁵⁶, C. Hasse⁴⁴, M. Hatch⁴⁴, J. He⁴, M. Hecker⁵⁷, K. Heinicke¹²,
A. Heister¹², K. Hennessy⁵⁶, L. Henry⁷⁶, M. Heß⁷⁰, J. Heuel¹¹, A. Hicheur⁶⁴,
R. Hidalgo Charman⁵⁸, D. Hill⁵⁹, M. Hilton⁵⁸, P.H. Hopchev⁴⁵, J. Hu¹⁴, W. Hu⁶⁸, W. Huang⁴,
Z.C. Huard⁶¹, W. Hulsbergen²⁹, T. Humair⁵⁷, M. Hushchyn⁷⁴, D. Hutchcroft⁵⁶, D. Hynds²⁹,
P. Ibis¹², M. Idzik³², P. Ilten⁴⁹, A. Inglessi³⁵, A. Inyakin⁴¹, K. Ivshin³⁵, R. Jacobsson⁴⁴,
J. Jalocha⁵⁹, E. Jans²⁹, B.K. Jashal⁷⁶, A. Jawahery⁶², F. Jiang³, M. John⁵⁹, D. Johnson⁴⁴,
C.R. Jones⁵¹, C. Joram⁴⁴, B. Jost⁴⁴, N. Jurik⁵⁹, S. Kandybei⁴⁷, M. Karacson⁴⁴, J.M. Kariuki⁵⁰,
S. Karodia⁵⁵, N. Kazeev⁷⁴, M. Kecke¹⁴, F. Keizer⁵¹, M. Kelsey⁶³, M. Kenzie⁵¹, T. Ketel³⁰,
E. Khairullin³⁹, B. Khanji⁴⁴, C. Khurewathanakul⁴⁵, K.E. Kim⁶³, T. Kirn¹¹, V.S. Kirsebom⁴⁵,
S. Klaver²⁰, K. Klimaszewski³³, T. Klimkovich¹³, S. Koliiev⁴⁸, M. Kolpin¹⁴, R. Kopecna¹⁴,
P. Koppenburg²⁹, I. Kostiuk²⁹,⁴⁸, S. Kotriakhova³⁵, M. Kozeiha⁷, L. Kravchuk³⁸, M. Kreps⁵²,
F. Kress⁵⁷, P. Krokovny⁴⁰,ₓ, W. Krupa³², W. Krzemien³³, W. Kucewicz³¹, l, M. Kucharczyk³¹,
V. Kudryavtsev⁴⁰,ₓ, A.K. Kuonen⁴⁵, T. Kvaratskheliya³⁶,⁴⁴, D. Lacarrere⁴⁴, G. Lafferty⁵⁸,
A. Lai²⁴, D. Lancierini⁴⁶, G. Lanfranchi²⁰, C. Langenbruch¹¹, T. Latham⁵², C. Lazzeroni⁴⁹,
R. Le Gac⁸, R. Lefèvre⁷, A. Leflat³⁷, F. Lemaitre⁴⁴, O. Leroy⁸, T. Lesiak³¹, B. Leverington¹⁴,
P.-R. Li⁴,ab, Y. Li⁵, Z. Li⁶³, X. Liang⁶³, T. Likhomanenko⁷², R. Lindner⁴⁴, F. Lionetto⁴⁶,
V. Lisovskyi⁹, G. Liu⁶⁶, X. Liu³, D. Loh⁵², A. Loi²⁴, I. Longstaff⁵⁵, J.H. Lopes², G.H. Lovell⁵¹,
D. Lucchesi²⁵, o, M. Lucio Martinez⁴³, Y. Luo³, A. Lupato²⁵, E. Luppi¹⁸, g, O. Lupton⁴⁴,
A. Lusiani²⁶, X. Lyu⁴, F. Machefert⁹, F. Maciuc³⁴, V. Macko⁴⁵, P. Mackowiak¹²,
S. Maddrell-Mander⁵⁰, O. Maev³⁵,⁴⁴, K. Maguire⁵⁸, D. Maisuzenko³⁵, M.W. Majewski³²,
S. Malde⁵⁹, B. Malecki⁴⁴, A. Malinin⁷², T. Maltsev⁴⁰,ₓ, H. Malygina¹⁴, G. Manca²⁴,f,
G. Mancinelli⁸, D. Marangotto²³,q, J. Maratas⁷, w, J.F. Marchand⁶, U. Marconi¹⁷,
C. Marin Benito⁹, M. Marinangeli⁴⁵, P. Marino⁴⁵, J. Marks¹⁴, P.J. Marshall⁵⁶, G. Martellotti²⁸,
M. Martinelli⁴⁴, D. Martinez Santos⁴³, F. Martinez Vidal⁷⁶, A. Massafferri¹, M. Materok¹¹,
R. Matev⁴⁴, A. Mathad⁵², Z. Mathe⁴⁴, C. Matteuzzi²², A. Mauri⁴⁶, E. Maurice⁹, b, B. Maurin⁴⁵,
M. McCann⁵⁷,⁴⁴, A. McNab⁵⁸, R. McNulty¹⁵, J.V. Mead⁵⁶, B. Meadows⁶¹, C. Meaux⁸,
N. Meinert⁷⁰, D. Melnychuk³³, M. Merk²⁹, A. Merli²³,q, E. Michielin²⁵, D.A. Milanes⁶⁹,
E. Millard⁵², M.-N. Minard⁶, L. Minzoni¹⁸, g, D.S. Mitzel¹⁴, A. Mödden¹², A. Mogini¹⁰,
R.D. Moise⁵⁷, T. Mombächer¹², I.A. Monroy⁶⁹, S. Monteil⁷, M. Morandin²⁵, G. Morello²⁰,
M.J. Morello²⁶, t, O. Morgunova⁷², J. Moron³², A.B. Morris⁸, R. Mountain⁶³, F. Muheim⁵⁴,
M. Mukherjee⁶⁸, M. Mulder²⁹, D. Müller⁴⁴, J. Müller¹², K. Müller⁴⁶, V. Müller¹²,
C.H. Murphy⁵⁹, D. Murray⁵⁸, P. Naik⁵⁰, T. Nakada⁴⁵, R. Nandakumar⁵³, A. Nandi⁵⁹,
T. Nanut⁴⁵, I. Nasteva², M. Needham⁵⁴, N. Neri²³, q, S. Neubert¹⁴, N. Neufeld⁴⁴,
R. Newcombe⁵⁷, T.D. Nguyen⁴⁵, C. Nguyen-Mau⁴⁵, n, S. Nieswand¹¹, R. Niet¹², N. Nikitin³⁷,
A. Nogay⁷², N.S. Nolte⁴⁴, A. Oblakowska-Mucha³², V. Obraztsov⁴¹, S. Ogilvy⁵⁵,
D.P. O'Hanlon¹⁷, R. Oldeman²⁴, f, C.J.G. Onderwater⁷¹, A. Ossowska³¹,
J.M. Otalora Goicochea², T. Ovsiannikova³⁶, P. Owen⁴⁶, A. Oyanguren⁷⁶, P.R. Pais⁴⁵,
T. Pajero²⁶, t, A. Palano¹⁶, M. Palutan²⁰, G. Panshin⁷⁵, A. Papanestis⁵³, M. Pappagallo⁵⁴,
L.L. Pappalardo¹⁸, g, W. Parker⁶², C. Parkes⁵⁸,⁴⁴, G. Passaleva¹⁹,⁴⁴, A. Pastore¹⁶, M. Patel⁵⁷,
C. Patrignani¹⁷, e, A. Pearce⁴⁴, A. Pellegrino²⁹, G. Penso²⁸, M. Pepe Altarelli⁴⁴, S. Perazzini⁴⁴,
D. Pereima³⁶, P. Perret⁷, L. Pescatore⁴⁵, K. Petridis⁵⁰, A. Petrolini²¹, h, A. Petrov⁷²,
S. Petrucci⁵⁴, M. Petruzzo²³, q, B. Pietrzyk⁶, G. Pietrzyk⁴⁵, M. Pikies³¹, M. Pili⁵⁹, D. Pinci²⁸,
J. Pinzino⁴⁴, F. Pisani⁴⁴, A. Piucci¹⁴, V. Placinta³⁴, S. Playfer⁵⁴, J. Plews⁴⁹, M. Plo Casasus⁴³,
F. Polci¹⁰, M. Poli Lener²⁰, A. Poluektov⁸, N. Polukhina⁷³, c, I. Polyakov⁶³, E. Polycarpo²,
G.J. Pomery⁵⁰, S. Ponce⁴⁴, A. Popov⁴¹, D. Popov⁴⁹,¹³, S. Poslavskii⁴¹, E. Price⁵⁰, J. Prisciandaro⁴³, C. Prouve⁴³, V. Pugatch⁴⁸, A. Puig Navarro⁴⁶, H. Pullen⁵⁹, G. Punzi²⁶,ₚ, W. Qian<fnref n="4" />, J. Qin<fnref n="4" />, R. Quagliani¹⁰, B. Quintana⁷, N.V. Raab¹⁵, B. Rachwal³², J.H. Rademacker⁵⁰, M. Rama²⁶, M. Ramos Pernas⁴³, M.S. Rangel<fnref n="2" />, F. Ratnikov³⁹,⁷⁴, G. Raven³⁰, M. Ravonel Salzgeber⁴⁴, M. Reboud<fnref n="6" />, F. Redi⁴⁵, S. Reichert¹², F. Reiss¹⁰, C. Remon Alepuz⁷⁶, Z. Ren<fnref n="3" />, V. Renaudin⁵⁹, S. Ricciardi⁵³, S. Richards⁵⁰, K. Rinnert⁵⁶, P. Robbe⁹, A. Robert¹⁰, A.B. Rodrigues⁴⁵, E. Rodrigues⁶¹, J.A. Rodriguez Lopez⁶⁹, M. Roehrken⁴⁴, S. Roiser⁴⁴, A. Rollings⁵⁹, V. Romanovskiy⁴¹, A. Romero Vidal⁴³, J.D. Roth⁷⁷, M. Rotondo²⁰, M.S. Rudolph⁶³, T. Ruf⁴⁴, J. Ruiz Vidal⁷⁶, J.J. Saborido Silva⁴³, N. Sagidova³⁵, B. Saitta²⁴,ₚ, V. Salustino Guimaraes⁶⁵, C. Sanchez Gras²⁹, C. Sanchez Mayordomo⁷⁶, B. Sanmartin Sedes⁴³, R. Santacesaria²⁸, C. Santamarina Rios⁴³, M. Santimaria²⁰,⁴⁴, E. Santovetti²⁷,ₚ, G. Sarpis⁵⁸, A. Sarti²⁰,ₖ, C. Satriano²⁸,ₙ, A. Satta²⁷, M. Saur<fnref n="4" />, D. Savrina³⁶,³⁷, S. Schael¹¹, M. Schellenberg¹², M. Schiller⁵⁵, H. Schindler⁴⁴, M. Schmelling¹³, T. Schmelzer¹², B. Schmidt⁴⁴, O. Schneider⁴⁵, A. Schopper⁴⁴, H.F. Schreiner⁶¹, M. Schubiger⁴⁵, S. Schulte⁴⁵, M.H. Schune⁹, R. Schwemmer⁴⁴, B. Sciascia²⁰, A. Sciubba²⁸,ₖ, A. Semennikov³⁶, E.S. Sepulveda¹⁰, A. Sergi⁴⁹, N. Serra⁴⁶, J. Serrano⁸, L. Sestini²⁵, A. Seuthe¹², P. Seyfert⁴⁴, M. Shapkin⁴¹, Y. Shcheglov³⁵,†, T. Shears⁵⁶, L. Shekhtman⁴⁰,ₓ, V. Shevchenko⁷², E. Shmanin⁷³, B.G. Siddi¹⁸, R. Silva Coutinho⁴⁶, L. Silva de Oliveira<fnref n="2" />, G. Simi²⁵,, S. Simone¹⁶,ₚ, I. Skiba¹⁸, N. Skidmore¹⁴, T. Skwarnicki⁶³, M.W. Slater⁴⁹, J.G. Smeaton⁵¹, E. Smith¹¹, I.T. Smith⁵⁴, M. Smith⁵⁷, M. Soares¹⁷, l. Soares Lavra<fnref n="1" />, M.D. Sokoloff⁶¹, F.J.P. Soler⁵⁵, B. Souza De Paula<fnref n="2" />, B. Spaan¹², E. Spadaro Norella²³,ₚ, P. Spradlin⁵⁵, F. Stagni⁴⁴, M. Stahl¹⁴, S. Stahl⁴⁴, P. Stefko⁴⁵, S. Stefkova⁵⁷, O. Steinkamp⁴⁶, S. Stemmle¹⁴, O. Stenyakin⁴¹, M. Stepanova³⁵, H. Stevens¹², A. Stocchi⁹, S. Stone⁶³, B. Storaci⁴⁶, S. Stracka²⁶, M.E. Stramaglia⁴⁵, M. Straticiuc³⁴, U. Straumann⁴⁶, S. Strokov⁷⁵, J. Sun<fnref n="3" />, L. Sun⁶⁷, Y. Sun⁶², K. Swientek³², A. Szabelski³³, T. Szumlak³², M. Szymanski<fnref n="4" />, Z. Tang<fnref n="3" />, T. Tekampe¹², G. Tellarini¹⁸, F. Teubert⁴⁴, E. Thomas⁴⁴, M.J. Tilley⁵⁷, V. Tisserand⁷, S. T'Jumpens<fnref n="6" />, M. Tobin³², S. Tolk⁴⁴, L. Tomassetti¹⁸,ₚ, D. Tonelli²⁶, D.Y. Tou¹⁰, R. Tourinho Jadallah Aoude<fnref n="1" />, E. Tournefier<fnref n="6" />, M. Traill⁵⁵, M.T. Tran⁴⁵, A. Trisovic⁵¹, A. Tsaregorodtsev⁸, G. Tuci²⁶,ₚ, A. Tully⁵¹, N. Tuning²⁹,⁴⁴, A. Ukleja³³, A. Usachov⁹, A. Ustyuzhanin³⁹,⁷⁴, U. Uwer¹⁴, A. Vagner⁷⁵, V. Vagnoni¹⁷, A. Valassi⁴⁴, S. Valat⁴⁴, G. Valenti¹⁷, M. van Beuzekom²⁹, E. van Herwijnen⁴⁴, J. van Tilburg²⁹, M. van Veghel²⁹, R. Vazquez Gomez⁴⁴, P. Vazquez Regueiro⁴³, C. Vázquez Sierra²⁹, S. Vecchi¹⁸, J.J. Velthuis⁵⁰, M. Veltri¹⁹,ₚ, G. Veneziano⁵⁹, A. Venkateswaran⁶³, M. Vernet⁷, M. Veronesi²⁹, M. Vesterinen⁵², J.V. Viana Barbosa⁴⁴, D. Vieira<fnref n="4" />, M. Vieites Diaz⁴³, H. Viemann⁷⁰, X. Vilasis-Cardona⁴²,ₘ, A. Vitkovskiy²⁹, M. Vitti⁵¹, V. Volkov³⁷, A. Vollhardt⁴⁶, D. Vom Bruch¹⁰, B. Voneki⁴⁴, A. Vorobyev³⁵, V. Vorobyev⁴⁰,ₓ, N. Voropaev³⁵, R. Waldi⁷⁰, J. Walsh²⁶, J. Wang<fnref n="5" />, M. Wang<fnref n="3" />, Y. Wang⁶⁸, Z. Wang⁴⁶, D.R. Ward⁵¹, H.M. Wark⁵⁶, N.K. Watson⁴⁹, D. Websdale⁵⁷, A. Weiden⁴⁶, C. Weisser⁶⁰, M. Whitehead¹¹, G. Wilkinson⁵⁹, M. Wilkinson⁶³, I. Williams⁵¹, M. Williams⁶⁰, M.R.J. Williams⁵⁸, T. Williams⁴⁹, F.F. Wilson⁵³, M. Winn⁹, W. Wislicki³³, M. Witek³¹, G. Wormser⁹, S.A. Wotton⁵¹, K. Wyllie⁴⁴, D. Xiao⁶⁸, Y. Xie⁶⁸, A. Xu<fnref n="3" />, M. Xu⁶⁸, Q. Xu<fnref n="4" />, Z. Xu<fnref n="6" />, Z. Xu<fnref n="3" />, Z. Yang<fnref n="3" />, Z. Yang⁶², Y. Yao⁶³, L.E. Yeomans⁵⁶, H. Yin⁶⁸, J. Yu⁶⁸,aa, X. Yuan⁶³, O. Yushchenko⁴¹, K.A. Zarebski⁴⁹, M. Zavertyaev¹³,ₚ, D. Zhang⁶⁸, L. Zhang<fnref n="3" />, W.C. Zhang<fnref n="3" />,, Y. Zhang⁴⁴, A. Zhelezov¹⁴, Y. Zheng<fnref n="4" />, X. Zhu<fnref n="3" />, V. Zhukov¹¹,³⁷, J.B. Zonneveld⁵⁴, S. Zucchelli¹⁷, e.

<footnote n="1">¹Centro Brasileiro de Pesquisas Físicas (CBPF), Rio de Janeiro, Brazil</footnote>

<footnote n="2">²Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil</footnote>

<footnote n="3">³Center for High Energy Physics, Tsinghua University, Beijing, China</footnote>

<footnote n="4">⁴University of Chinese Academy of Sciences, Beijing, China</footnote>

<footnote n="5">⁵Institute Of High Energy Physics (ihep), Beijing, China</footnote>

<footnote n="6">⁶Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, IN2P3-LAPP, Annecy, France</footnote>
⁷ Université Clermont Auvergne, CNRS/IN2P3, LPC, Clermont-Ferrand, France

⁸ Aix Marseille Univ, CNRS/IN2P3, CPPM, Marseille, France

⁹ LAL, Univ. Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, Orsay, France

¹⁰ LPNHE, Sorbonne Université, Paris Diderot Sorbonne Paris Cité, CNRS/IN2P3, Paris, France

¹¹ I. Physikalisches Institut, RWTH Aachen University, Aachen, Germany

¹² Fakultät Physik, Technische Universität Dortmund, Dortmund, Germany

¹³ Max-Planck-Institut für Kernphysik (MPIK), Heidelberg, Germany

¹⁴ Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany

¹⁵ School of Physics, University College Dublin, Dublin, Ireland

¹⁶ INFN Sezione di Bari, Bari, Italy

¹⁷ INFN Sezione di Bologna, Bologna, Italy

¹⁸ INFN Sezione di Ferrara, Ferrara, Italy

¹⁹ INFN Sezione di Firenze, Firenze, Italy

²⁰ INFN Laboratori Nazionali di Frascati, Frascati, Italy

²¹ INFN Sezione di Genova, Genova, Italy

²² INFN Sezione di Milano-Bicocca, Milano, Italy

²³ INFN Sezione di Milano, Milano, Italy

²⁴ INFN Sezione di Cagliari, Monserrato, Italy

²⁵ INFN Sezione di Padova, Padova, Italy

²⁶ INFN Sezione di Pisa, Pisa, Italy

²⁷ INFN Sezione di Roma Tor Vergata, Roma, Italy

²⁸ INFN Sezione di Roma La Sapienza, Roma, Italy

²⁹ Nikhef National Institute for Subatomic Physics, Amsterdam, Netherlands

³⁰ Nikhef National Institute for Subatomic Physics and VU University Amsterdam, Amsterdam, Netherlands

³¹ Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences, Kraków, Poland

³² AGH - University of Science and Technology, Faculty of Physics and Applied Computer Science, Kraków, Poland

³³ National Center for Nuclear Research (NCBJ), Warsaw, Poland

³⁴ Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest-Magurele, Romania

³⁵ Petersburg Nuclear Physics Institute (PNPI), Gatchina, Russia

³⁶ Institute of Theoretical and Experimental Physics (ITEP), Moscow, Russia

³⁷ Institute of Nuclear Physics, Moscow State University (SINP MSU), Moscow, Russia

³⁸ Institute for Nuclear Research of the Russian Academy of Sciences (INR RAS), Moscow, Russia

³⁹ Yandex School of Data Analysis, Moscow, Russia

⁴⁰ Budker Institute of Nuclear Physics (SB RAS), Novosibirsk, Russia

⁴¹ Institute for High Energy Physics (IHEP), Protvino, Russia

⁴² ICCUB, Universitat de Barcelona, Barcelona, Spain

⁴³ Instituto Galego de Física de Altas Enerxías (IGFAE), Universidade de Santiago de Compostela, Santiago de Compostela, Spain

⁴⁴ European Organization for Nuclear Research (CERN), Geneva, Switzerland

⁴⁵ Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland

⁴⁶ Physik-Institut, Universität Zürich, Zürich, Switzerland

⁴⁷ NSC Kharkiv Institute of Physics and Technology (NSC KIPT), Kharkiv, Ukraine

⁴⁸ Institute for Nuclear Research of the National Academy of Sciences (KINR), Kyiv, Ukraine

⁴⁹ University of Birmingham, Birmingham, United Kingdom

⁵⁰ H.H. Wills Physics Laboratory, University of Bristol, Bristol, United Kingdom

⁵¹ Cavendish Laboratory, University of Cambridge, Cambridge, United Kingdom

⁵² Department of Physics, University of Warwick, Coventry, United Kingdom

⁵³ STFC Rutherford Appleton Laboratory, Didcot, United Kingdom

⁵⁴ School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom

⁵⁵ School of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom

⁵⁶ Oliver Lodge Laboratory, University of Liverpool, Liverpool, United Kingdom

⁵⁷ Imperial College London, London, United Kingdom

⁵⁸ School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom

⁵⁹ Department of Physics, University of Oxford, Oxford, United Kingdom
⁶⁰ Massachusetts Institute of Technology, Cambridge, MA, United States

⁶¹ University of Cincinnati, Cincinnati, OH, United States

⁶² University of Maryland, College Park, MD, United States

⁶³ Syracuse University, Syracuse, NY, United States

⁶⁴ Laboratory of Mathematical and Subatomic Physics, Constantine, Algeria, associated to ²

⁶⁵ Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio), Rio de Janeiro, Brazil, associated to ²

⁶⁶ South China Normal University, Guangzhou, China, associated to ³

⁶⁷ School of Physics and Technology, Wuhan University, Wuhan, China, associated to ³

⁶⁸ Institute of Particle Physics, Central China Normal University, Wuhan, Hubei, China, associated to ³

⁶⁹ Departamento de Física, Universidad Nacional de Colombia, Bogota, Colombia, associated to ¹⁰

⁷⁰ Institut für Physik, Universität Rostock, Rostock, Germany, associated to ¹⁴

⁷¹ Van Swinderen Institute, University of Groningen, Groningen, Netherlands, associated to ²⁹

⁷² National Research Centre Kurchatov Institute, Moscow, Russia, associated to ³⁶

⁷³ National University of Science and Technology “MISIS”, Moscow, Russia, associated to ³⁶

⁷⁴ National Research University Higher School of Economics, Moscow, Russia, associated to ³⁹

⁷⁵ National Research Tomsk Polytechnic University, Tomsk, Russia, associated to ³⁶

⁷⁶ Instituto de Física Corpuscular, Centro Mixto Universidad de Valencia - CSIC, Valencia, Spain, associated to ⁴²

⁷⁷ University of Michigan, Ann Arbor, United States, associated to ⁶³

⁷⁸ Los Alamos National Laboratory (LANL), Los Alamos, United States, associated to ⁶³

ª Universidade Federal do Triângulo Mineiro (UFTM), Uberaba-MG, Brazil

ᵇ Laboratoire Leprince-Ringuet, Palaiseau, France

ᶜ P.N. Lebedev Physical Institute, Russian Academy of Science (LPI RAS), Moscow, Russia

ᵈ Università di Bari, Bari, Italy

ᵉ Università di Bologna, Bologna, Italy

f Università di Cagliari, Cagliari, Italy

⁹ Università di Ferrara, Ferrara, Italy

h Università di Genova, Genova, Italy

i Università di Milano Bicocca, Milano, Italy

j Università di Roma Tor Vergata, Roma, Italy

k Università di Roma La Sapienza, Roma, Italy

l AGH - University of Science and Technology, Faculty of Computer Science, Electronics and Telecommunications, Kraków, Poland

m LIFAELS, La Salle, Universitat Ramon Llull, Barcelona, Spain

ⁿ Hanoi University of Science, Hanoi, Vietnam

o Università di Padova, Padova, Italy

p Università di Pisa, Pisa, Italy

q Università degli Studi di Milano, Milano, Italy

r Università di Urbino, Urbino, Italy

s Università della Basilicata, Potenza, Italy

t Scuola Normale Superiore, Pisa, Italy

u Università di Modena e Reggio Emilia, Modena, Italy

v H.H. Wills Physics Laboratory, University of Bristol, Bristol, United Kingdom

w MSU - Iligan Institute of Technology (MSU-IIT), Iligan, Philippines

x Novosibirsk State University, Novosibirsk, Russia

y Sezione INFN di Trieste, Trieste, Italy

z School of Physics and Information Technology, Shaanxi Normal University (SNNU), Xi'an, China

aa Physics and Micro Electronic College, Hunan University, Changsha City, China

ab Lanzhou University, Lanzhou, China

† Deceased