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A<sc>bstract</sc> This paper presents a study of the charmless three-body decays$$ {B}_{(s)}^0\to {K}_{\mathrm{S}}^0{h}^{+}h{\prime}^{-} $$ $B_{\left(s\right)}^0\to K_S^0{h}^{+}h{\prime }^{-}$ (whereh⁽′⁾=π, K), using a sample ofppcollision data collected by the LHCb experiment during Runs 1 and 2 of the LHC, corresponding to an integrated luminosity of 9 fb⁻¹. The decay$$ {B}_s^0\to {K}_{\mathrm{S}}^0{K}^{+}{K}^{-} $$ $B_s^0\to K_S^0{K}^{+}{K}^{-}$ is observed for the first time, and the following ratios of branching fractions are measured:$$ {\displaystyle \begin{array}{l}\frac{\mathcal{B}\left({B}^0\to {K}_{\mathrm{S}}^0{K}^{+}{K}^{-}\right)}{\mathcal{B}\left({B}^0\to {K}_{\mathrm{S}}^0{\pi}^{+}{\pi}^{-}\right)}=0.578\pm 0.007\pm 0.017,\\ {}\frac{\mathcal{B}\left({B}^0\to {K}_{\mathrm{S}}^0{K}^{\pm }{K}^{\mp}\right)}{\mathcal{B}\left({B}^0\to {K}_{\mathrm{S}}^0{\pi}^{+}{\pi}^{-}\right)}=0.1363\pm 0.0035\pm 0.051,\\ {}\begin{array}{l}\frac{\mathcal{B}\left({B}_s^0\to {K}_{\mathrm{S}}^0{\pi}^{+}{\pi}^{-}\right)}{\mathcal{B}\left({B}^0\to {K}_{\mathrm{S}}^0{\pi}^{+}{\pi}^{-}\right)}=0.269\pm 0.011\pm 0.015\pm 0.008,\\ {}\frac{\mathcal{B}\left({B}_s^0\to {K}_{\mathrm{S}}^0{K}^{+}{K}^{-}\right)}{\mathcal{B}\left({B}^0\to {K}_{\mathrm{S}}^0{\pi}^{+}{\pi}^{-}\right)}=0.0303\pm 0.0041\pm 0.0025\pm 0.0009,\\ {}\frac{\mathcal{B}\left({B}_s^0\to {K}_{\mathrm{S}}^0{K}^{\pm }{\pi}^{\mp}\right)}{\mathcal{B}\left({B}^0\to {K}_{\mathrm{S}}^0{\pi}^{+}{\pi}^{-}\right)}=1.818\pm 0.021\pm 0.031\pm 0.056,\end{array}\end{array}} $$ $\begin{array}{c}\frac{B\left(B^0\to K_S^0{K}^{+}{K}^{-}\right)}{B\left(B^0\to K_S^0{\pi }^{+}{\pi }^{-}\right)}=0.578\pm 0.007\pm 0.017,\\ \frac{B\left(B^0\to K_S^0{K}^{\pm }{K}^{\mp }\right)}{B\left(B^0\to K_S^0{\pi }^{+}{\pi }^{-}\right)}=0.1363\pm 0.0035\pm 0.051,\\ \begin{array}{c}\frac{B\left(B_s^0\to K_S^0{\pi }^{+}{\pi }^{-}\right)}{B\left(B^0\to K_S^0{\pi }^{+}{\pi }^{-}\right)}=0.269\pm 0.011\pm 0.015\pm 0.008,\\ \frac{B\left(B_s^0\to K_S^0{K}^{+}{K}^{-}\right)}{B\left(B^0\to K_S^0{\pi }^{+}{\pi }^{-}\right)}=0.0303\pm 0.0041\pm 0.0025\pm 0.0009,\\ \frac{B\left(B_s^0\to K_S^0{K}^{\pm }{\pi }^{\mp }\right)}{B\left(B^0\to K_S^0{\pi }^{+}{\pi }^{-}\right)}=1.818\pm 0.021\pm 0.031\pm 0.056,\end{array}\end{array}$ where the uncertainties are statistical, systematic, and due to knowledge of the ratio of hadronisation fractions of the$$ {B}_s^0 $$ $B_s^0$ andB⁰mesons, respectively. 

The time-dependent $CP$ asymmetry in $B^0\to J/\psi \rho (770{)}^0$ decays is measured using proton-proton collision data corresponding to an integrated luminosity of $6{\mathrm{fb}}^{-1}$ , collected with the LHCb detector at a center-of-mass energy of 13 TeV during the years 2015–2018. The $CP$ -violation parameters for this process are determined to be $2{\beta }_{c\overline{c}d}^{\mathrm{eff}}=0.710\pm 0.084\pm 0.051\mathrm{rad}$ and $\left|\lambda \right|=1.019\pm 0.034\pm 0.024$ , where the first uncertainty is statistical and the second systematic. This constitutes the first observation of time-dependent $CP$ violation in $B^0\to J/\psi \rho (770{)}^0$ decays. Assuming approximate SU(3) flavor symmetry, these results are combined with the previous consistent LHCb measurement to set the most stringent constraint on the penguin contribution, $\mathrm{\Delta }{\varphi }_s$ , to the $CP$ -violating phase ${\varphi }_s$ in $B_s^0\to J/\psi \varphi \left(1020\right)$ decays, yielding $\mathrm{\Delta }{\varphi }_s=5.0\pm 4.6\mathrm{mrad}$ . 

Muon-electron universality is tested in $B^0\to K^{*0}{\ell }^{+}{\ell }^{-}$ decays, in the dilepton-invariant-mass region above the $\psi \left(2S\right)$ resonance. The analysis uses beauty mesons produced in proton-proton collisions recorded by the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$ . The ratio of branching fractions between the muon and electron channels $R_{K^{*0}}$ is measured to be ${1.08}_{-0.12}^{+0.14}\left(\mathrm{stat}\right)\pm 0.07\left(\mathrm{syst}\right)$ for a dilepton-invariant-mass squared above $14.0{\mathrm{GeV}}^2/c^4$ , consistent with the standard model prediction. This result represents the most precise measurement of $R_{K^{*0}}$ in this region and the first such measurement performed at a hadron collider. 

The first observation of the doubly charmed baryon ${\mathrm{\Xi }}_{cc}^{+}$ is reported through its decay to the ${\mathrm{\Lambda }}_c^{+}{K}^{-}{\pi }^{+}$ final state, with a statistical significance exceeding seven standard deviations. The observation is made using proton-proton collision data collected in 2024 with the LHCb Run 3 detector at a center-of-mass energy of 13.6 TeV, corresponding to a total integrated luminosity of $6.9{\mathrm{fb}}^{-1}$ . The ${\mathrm{\Xi }}_{cc}^{+}$ mass is measured to be $3619.97\pm 0.83\pm {0.26}_{-1.30}^{+1.90}\mathrm{MeV}/c^2$ , where the first uncertainty is statistical, the second is systematic, and the third is due to the unknown ${\mathrm{\Xi }}_{cc}^{+}$ lifetime, which is assumed to lie in the range 15–160 fs with a baseline value of 45 fs. The difference between the masses of the ${\mathrm{\Xi }}_{cc}^{+}$ and ${\mathrm{\Xi }}_{cc}^{++}$ baryons is determined to be $-1.77\pm 0.84\pm {0.15}_{-1.30}^{+1.90}\mathrm{MeV}/c^2$ . This is the first observation of a new particle made with the LHCb Run 3 detector. 

A search for the rare decay $B^{+}\to \overline{\mathrm{\Lambda }}p{\mu }^{+}{\mu }^{-}$ is performed using proton-proton collision data recorded by the LHCb experiment at a center-of-mass energy of $\sqrt{s}=13\mathrm{TeV}$ , corresponding to an integrated luminosity of $5.4{\mathrm{fb}}^{-1}$ . An excess of events is found with respect to the background-only expectation, with a signal significance of 3.5 standard deviations, in the low invariant-mass region of $m\left(\overline{\mathrm{\Lambda }}p\right)<2.8\mathrm{GeV}/c^2$ . The branching fraction is measured to be ${\mathcal{B}}_{\mathrm{low}}(B^{+}\to \overline{\mathrm{\Lambda }}p{\mu }^{+}{\mu }^{-})=\left(1.70_{-0.56}^{+0.65}\right(\mathrm{stat})\pm 0.17(\mathrm{syst})\pm 0.14(\mathrm{ext}\left)\right)\times {10}^{-8}$ , where the last uncertainty is due to external inputs on $\mathcal{B}(B^{+}\to J/\psi \overline{\mathrm{\Lambda }}p)\times \mathcal{B}(J/\psi \to {\mu }^{+}{\mu }^{-})$ . With no significant signal observed in the high $m\left(\overline{\mathrm{\Lambda }}p\right)$ region above $2.8\mathrm{GeV}/c^2$ , an upper limit is set to be ${\mathcal{B}}_{\mathrm{high}}(B^{+}\to \overline{\mathrm{\Lambda }}p{\mu }^{+}{\mu }^{-})<2.8\left(3.7\right)\times {10}^{-9}$ at the 90% (95%) confidence level. 

An analysis of the $B^0\to K^{*0}(\to K^{+}{\pi }^{-}){\mu }^{+}{\mu }^{-}$ decay is presented using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of $8.4{\mathrm{fb}}^{-1}$ . The full set of $CP$ -averaged and $CP$ -asymmetric angular observables is determined in bins of the invariant mass squared of the dimuon system, as well as the branching fraction relative to the $B^0\to J/\psi (\to {\mu }^{+}{\mu }^{-})K^{+}{\pi }^{-}$ decay. For the first time, the full set of observables pertaining to the $K^{+}{\pi }^{-}$ S-wave contribution to the final state are presented and consideration is given to effects arising from the mass of the muons. The extracted $CP$ -asymmetry observables show no significant deviations from zero. The measurements of the $CP$ -averaged observables and the branching fractions continue to exhibit the pattern of tensions with the standard model predictions that have been seen in previous analyses that use part of the dataset considered in this Letter. 

The decay $B^0\to {\mathrm{\Lambda }}_c^{+}{\overline{\mathrm{\Lambda }}}_c^{-}{K}_{\mathrm{S}}^0$ is studied at LHCb for the first time using proton-proton collision data recorded by the LHCb experiment at a center-of-mass energy of $\sqrt{s}=13\mathrm{TeV}$ , corresponding to an integrated luminosity of $5.4{\mathrm{fb}}^{-1}$ . The branching ratio relative to the decay $B^{+}\to {\mathrm{\Lambda }}_c^{+}{\overline{\mathrm{\Lambda }}}_c^{-}{K}^{+}$ is measured to be [ $\mathcal{B}(B^0\to {\mathrm{\Lambda }}_c^{+}{\overline{\mathrm{\Lambda }}}_c^{-}{K}_{\mathrm{S}}^0)]/[\mathcal{B}(B^{+}\to {\mathrm{\Lambda }}_c^{+}{\overline{\mathrm{\Lambda }}}_c^{-}{K}^{+})]=0.53\pm 0.05\pm 0.05$ where the first uncertainty is statistical and the second is systematic. Evidence is found for contributions from two resonant states, ${\mathrm{\Xi }}_c(2923{)}^{+}$ and ${\mathrm{\Xi }}_c(2939{)}^{+}$ , in the ${\mathrm{\Lambda }}_c^{+}{K}_{\mathrm{S}}^0$ system. The two states show a significance of $3.9\sigma$ relative to the nonresonant hypothesis. These two ${\mathrm{\Xi }}_c^{+}$ states are consistent with being the isospin partners of the states observed in the ${\mathrm{\Lambda }}_c^{+}{K}^{-}$ system. 

Context. The Southern Photometric Local Universe Survey (S-PLUS) is a project to map ~9300 sq deg of the sky using twelve bands (seven narrow and five broadbands). Observations are performed with the T80-South telescope, a robotic telescope located at the Cerro Tololo Observatory in Chile. The survey footprint consists of several large contiguous areas, including fields at high and low galactic latitudes, and towards the Magellanic Clouds. S-PLUS uses fixed exposure times to reach point source depths of about 21 mag in the 𝑔riɀ and 20 mag in theuand the narrow filters. Aims. This paper describes the S-PLUS Data Release 4 (DR4), which includes calibrated images and derived catalogues for over 3000 sq deg, covering the aforementioned area. The catalogues provide multi-band photometry performed with the toolsDoPHOTandSExtractor– point spread function (PSF) and aperture photometry, respectively. In addition to the characterization, we also present the scientific potential of the data. Methods. We use statistical tools to present and compare the photometry obtained through different methods. Overall we find good agreement between the different methods, with a slight systematic offset of 0.05 mag between ourPSFand aperture photometry. We show that the astrometry accuracy is equivalent to that obtained in previous S-PLUS data releases, even in very crowded fields where photometric extraction is challenging. The depths of main survey (MS) photometry for a minimum signal-to-noise ratioS/N= 3 reach from ~19.5 for the bluer bands to ~21.5 mag on the red. The range of magnitudes over which accuratePSFphotometry is obtained is shallower, reaching ~19 to ~20.5 mag depending on the filter. Based on these photometric data, we provide star-galaxy-quasar classification and photometric redshift for millions of objects. Results. We demonstrate the versatility of the data by presenting the results of a project to identify members of four Abell galaxy clusters in the Local Universe. The S-PLUS DR4 data allow for a reliable assessment of cluster membership out to a large radius corresponding to 5 ×r₂₀₀. The S-PLUS DR4 can be accessed through the survey data portal. All the software used to generate the catalogues for this release and the scientific investigation presented is available in the collaboration GitHub repository. Conclusions. The S-PLUS DR4 consists of a large, calibrated public dataset, providing powerful ways for studying Galactic and extra-galactic objects through an extensive set of (broad and narrow) filters. 

A flavor-tagged time-dependent analysis of $B^0\to K_{\mathrm{S}}^0{\mu }^{+}{\mu }^{-}$ decays is performed across the full dimuon mass range excluding the $J/\psi$ and $\psi \left(2S\right)$ resonance regions. The analysis uses proton-proton collision data collected by the LHCb experiment in 2011–2018 at center-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$ . The $CP$ violation parameters are determined to be $C=-0.13\pm 0.32\pm 0.04$ , $S=+0.82\pm 0.29\pm 0.05$ , where the first uncertainties are statistical and the second are systematic. The results are consistent with the standard model prediction. This is the first experimental study of time-dependent $CP$ violation in $b\to s{\ell }^{+}{\ell }^{-}$ processes. 

The first measurements of the top- and antitop-quark differential production cross sections and the top-quark charge asymmetry in the forward region are presented, using proton-proton collision data collected by the LHCb experiment at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of $5.4{\mathrm{fb}}^{-1}$ . The total production cross sections of top and antitop quarks are also determined. Measurements are performed using the $\mu +b\text{-jet}$ final state within a fiducial region defined by $b$ -jet $p_{\mathrm{T},\text{jet}}>50\mathrm{GeV}$ and pseudorapidity $2.2<{\eta }_{\text{jet}}<4.0$ , with the muon from the $W$ -boson decay required to have $p_{\mathrm{T},\mu }>25\mathrm{GeV}$ and $2.0<{\eta }_{\mu }<4.5$ . The muon and $b$ -jet system must satisfy $p_{\mathrm{T}}(\mu +\text{jet})>20\mathrm{GeV}$ . The measured integrated production cross sections for the top and antitop quarks are ${\sigma }_t=0.95\pm 0.04\pm 0.08\pm 0.02\mathrm{pb}$ , ${\sigma }_{\overline{t}}=0.81\pm 0.03\pm 0.07\pm 0.02\mathrm{pb}$ , where the first uncertainty is statistical, the second systematic, and the third accounts for the luminosity uncertainty. The top-quark charge asymmetry is measured to be $A_C^t=0.08\pm 0.03\pm 0.01$ , where the first uncertainty is statistical and the second is systematic. These results are consistent with next-to-leading order Standard Model predictions.