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Measurements of the charge-dependent two-particle angular correlation function in proton-lead (pPb) collisions at a nucleon-nucleon center-of-mass energy of$$ \sqrt{s_{\textrm{NN}}} $$$\sqrt{s_{\mathrm{NN}}}$= 8.16 TeV and lead-lead (PbPb) collisions at$$ \sqrt{s_{\textrm{NN}}} $$$\sqrt{s_{\mathrm{NN}}}$= 5.02 TeV are reported. The pPb and PbPb data sets correspond to integrated luminosities of 186 nb⁻¹and 0.607 nb⁻¹, respectively, and were collected using the CMS detector at the CERN LHC. The charge-dependent correlations are characterized by balance functions of same- and opposite-sign particle pairs. The balance functions, which contain information about the creation time of charged particle pairs and the development of collectivity, are studied as functions of relative pseudorapidity (∆η) and relative azimuthal angle (∆ϕ), for various multiplicity and transverse momentum (p_T) intervals. A multiplicity dependence of the balance function is observed in ∆ηand ∆ϕfor both systems. The width of the balance functions decreases towards high-multiplicity collisions in the momentum region<2 GeV, for pPb and PbPb results. Integrals of the balance functions are presented in both systems, and a mild dependence of the charge-balancing fractions on multiplicity is observed. No multiplicity dependence is observed at higher transverse momentum. The data are compared withhydjet,hijing, andamptgenerator predictions, none of which capture completely the multiplicity dependence seen in the data. The comparison of results with different center-of-mass energies suggests that the balance functions become narrower at higher energies, which is consistent with the idea of delayed hadronization and the effect of radial flow.

The production of$\mathrm{\Upsilon }(2S)$and$\mathrm{\Upsilon }(3S)$mesons in lead-lead (Pb-Pb) and proton-proton ($pp$) collisions is studied in their dimuon decay channel using the CMS detector at the LHC. The$\mathrm{\Upsilon }(3S)$meson is observed for the first time in Pb-Pb collisions, with a significance above 5 standard deviations. The ratios of yields measured in Pb-Pb and$pp$collisions are reported for both the$\mathrm{\Upsilon }(2S)$and$\mathrm{\Upsilon }(3S)$mesons, as functions of transverse momentum and Pb-Pb collision centrality. These ratios, when appropriately scaled, are significantly less than unity, indicating a suppression of$\mathrm{\Upsilon }$yields in Pb-Pb collisions. This suppression increases from peripheral to central Pb-Pb collisions. Furthermore, the suppression is stronger for$\mathrm{\Upsilon }(3S)$mesons compared to$\mathrm{\Upsilon }(2S)$mesons, extending the pattern of sequential suppression of quarkonium states in nuclear collisions previously seen for the$J/\psi$,$\psi (2S)$,$\mathrm{\Upsilon }(1S)$, and$\mathrm{\Upsilon }(2S)$mesons.

Differential cross sections are measured for the standard model Higgs boson produced in association with vector bosons ($W$,$Z$) and decaying to a pair of$b$quarks. Measurements are performed within the framework of the simplified template cross sections. The analysis relies on the leptonic decays of the$W$and$Z$bosons, resulting in final states with 0, 1, or 2 electrons or muons. The Higgs boson candidates are either reconstructed from pairs of resolved$b$-tagged jets, or from single large-radius jets containing the particles arising from two$b$quarks. Proton-proton collision data at$\sqrt{s}=13\mathrm{TeV}$, collected by the CMS experiment in 2016–2018 and corresponding to a total integrated luminosity of$138{\mathrm{fb}}^{-1}$, are analyzed. The inclusive signal strength, defined as the product of the observed production cross section and branching fraction relative to the standard model expectation, combining all analysis categories, is found to be$\mu =1.15_{-0.20}^{+0.22}$. This corresponds to an observed (expected) significance of 6.3 (5.6) standard deviations.