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A<sc>bstract</sc> Inclusive and differential cross sections for Higgs boson production in proton-proton collisions at a centre-of-mass energy of 13.6 TeV are measured using data collected with the CMS detector at the LHC in 2022, corresponding to an integrated luminosity of 34.7 fb⁻¹. Events with the diphoton final state are selected, and the measured inclusive fiducial cross section is$${\sigma }_{\text{fid}}={74}\pm {11}{\left({\text{stat}}\right)}_{-4}^{+5}\left({\text{syst}}\right)$$fb, in agreement with the standard model prediction of 67.8 ± 3.8 fb. Differential cross sections are measured as functions of several observables: the Higgs boson transverse momentum and rapidity, the number of associated jets, and the transverse momentum of the leading jet in the event. Within the uncertainties, the differential cross sections agree with the standard model predictions. 

A measurement is presented of the cross section in proton-proton collisions for the production of two $W$bosons and one $Z$boson. It is based on data recorded by the CMS experiment at the CERN LHC at center-of-mass energies $\sqrt{s}=13$and 13.6 TeV, corresponding to an integrated luminosity of $200{\mathrm{fb}}^{-1}$. Events with four charged leptons (electrons or muons) in the final state are selected. Both nonresonant $WWZ$production and $ZH$production, with the Higgs boson decaying into two $W$bosons, are reported. For the first time, the two processes are measured separately in a simultaneous fit. Combining the two modes, signal strengths relative to the standard model (SM) predictions of ${0.75}_{-0.29}^{+0.34}$and ${1.74}_{-0.60}^{+0.71}$are measured for $\sqrt{s}=13$and 13.6 TeV, respectively. The observed (expected) significance for the triboson signal is 3.8 (2.5) standard deviations for $\sqrt{s}=13.6\mathrm{TeV}$, thus providing the first evidence for triboson production at this center-of-mass energy. Combining the two modes and the two center-of-mass energies, the inclusive signal strength relative to the SM prediction is measured to be ${1.03}_{-0.28}^{+0.31}$, with an observed (expected) significance of 4.5 (5.0) standard deviations. 

A<sc>bstract</sc> The first measurement of the dijet transverse momentum balancex_jin proton-lead (pPb) collisions at a nucleon-nucleon center-of-mass energy of$$\sqrt{{s}_{\text{NN}}}$$= 8.16 TeV is presented. Thex_jobservable, defined as the ratio of the subleading over leading jet transverse momentum in a dijet pair, is used to search for jet quenching effects. The data, corresponding to an integrated luminosity of 174.6 nb⁻¹, were collected with the CMS detector in 2016. Thex_jdistributions and their average values are studied as functions of the charged-particle multiplicity of the events and for various dijet rapidity selections. The latter enables probing hard scattering of partons carrying distinct nucleon momentum fractionsxin the proton- and lead-going directions. The former, aided by the high-multiplicity triggers, allows probing for potential jet quenching effects in high-multiplicity events (with up to 400 charged particles), for which collective phenomena consistent with quark-gluon plasma (QGP) droplet formation were previously observed. The ratios ofx_jdistributions for high- to low-multiplicity events are used to quantify the possible medium effects. These ratios are consistent with simulations of the hard-scattering process that do not include QGP production. These measurements set an upper limit on medium-induced energy loss of the subleading jet of 1.26% of its transverse momentum at the 90% confidence level in high multiplicity pPb events. 

A<sc>bstract</sc> A measurement of the top quark pair ($$ \textrm{t}\overline{\textrm{t}} $$ $t\overline{t}$) production cross section in proton-proton collisions at a centre-of-mass energy of 5.02 TeV is presented. The data were collected at the LHC in autumn 2017, in dedicated runs with low-energy and low-intensity conditions with respect to the default configuration, and correspond to an integrated luminosity of 302 pb⁻¹. The measurement is performed using events with one electron or muon, and multiple jets, at least one of them being identified as originating from a b quark (b tagged). Events are classified based on the number of all reconstructed jets and of b-tagged jets. Multivariate analysis techniques are used to enhance the separation between the signal and backgrounds. The measured cross section is$$ 62.5\pm 1.6{\left(\textrm{stat}\right)}_{-2.5}^{+2.6}\left(\textrm{syst}\right)\pm 1.2\left(\textrm{lumi}\right) $$ $62.5\pm 1.6{\left(\text{stat}\right)}_{-2.5}^{+2.6}\left(\text{syst}\right)\pm 1.2\left(\text{lumi}\right)$pb. A combination with the result in the dilepton channel based on the same data set yields a value of 62.3 ± 1.5 (stat) ± 2.4 (syst) ± 1.2 (lumi) pb, to be compared with the standard model prediction of$$ {69.5}_{-3.7}^{+3.5} $$ ${69.5}_{-3.7}^{+3.5}$pb at next-to-next-to-leading order in perturbative quantum chromodynamics.