Measurements are presented of the W and Z boson production cross sections in proton-proton collisions at a center-of-mass energy of 13.6 TeV. Data collected in 2022 and corresponding to an integrated luminosity of 5.01 fb$^{-1}$ with one or two identified muons in the final state are analyzed. The results for the products of total inclusive cross sections and branching fractions for muonic decays of W and Z bosons are 11.93 $\pm$ 0.08 (syst) $\pm$ 0.17 (lumi) $^{+0.07}_{-0.07}$ (acc) nb for W$^+$ boson production, 8.86 $\pm$ 0.06 (syst) $\pm$ 0.12 (lumi) $^{+0.05}_{-0.06}$ (acc) nb for W$^-$ boson production, and 2.021 $\pm$ 0.009 (syst) $\pm$ 0.028 (lumi) $^{+0.011}_{-0.013}$ (acc) nb for the Z boson production in the dimuon mass range of 60-120 GeV, all with negligible statistical uncertainties. Furthermore, the corresponding fiducial cross sections, as well as cross section ratios for both fiducial and total phase space, are provided. The ratios include charge-separated results for W boson production (W$^+$ and W$^-$) and the sum of the two contributions (W$^\pm$), each relative to the measured Z boson production cross section. Additionally, the ratio of the measured cross sections for W$^+$ and W$^-$ boson production is reported. All measurements are in agreement with theoretical predictions, calculated at next-to-next-to-leading order accuracy in quantum chromodynamics.
Corrected normalized distribution of the transverse momentum of the leading muon in the Z boson signal region. Simulated contributions from Z boson, electroweak, and ttbar production, as well as their sum, and the data are shown.
Corrected normalized distribution of the transverse momentum of the trailing muon in the Z boson signal region. Simulated contributions from Z boson, electroweak, and ttbar production, as well as their sum, and the data are shown.
Corrected normalized distribution of the missing transverse momentum in the Z boson signal region. Simulated contributions from Z boson, electroweak, and ttbar production, as well as their sum, and the data are shown.
The measurements of the Higgs boson (H) production cross sections performed by the CMS Collaboration in the four-lepton (4$\ell$, $\ell$=e,$\mu$) final state at a center-of-mass energy $\sqrt{s}$ = 13.6 TeV are presented. These measurements are based on data collected with the CMS detector at the CERN LHC in 2022, corresponding to an integrated luminosity of 34.7 fb$^{-1}$. Cross sections are measured in a fiducial region closely matching the experimental acceptance, both inclusively and differentially, as a function of the transverse momentum and the absolute value of the rapidity of the four-lepton system. The H $\to$ ZZ $\to$ 4$\ell$ inclusive fiducial cross section is measured to be 2.89$^{+0.53}_{-0.49}$ (stat) $^{+0.29}_{-0.21}$ (syst) fb, in agreement with the standard model expectation of 3.09$^{+0.27}_{-0.24}$ fb.
Postfit reconstructed distribution of the 4-lepton invariant mass in the 70 < m4l < 350 GeV mass range.
Postfit reconstructed distribution of the 4-lepton invariant mass in the 105< m4l < 160 GeV mass range.
Measured inclusive fiducial H->ZZ->4l cross section in the various final states at 13.6 TeV.
Measurements of fiducial and total inclusive cross sections for W and Z boson production are presented in proton-proton collisions at $\sqrt{s}$ = 5.02 and 13 TeV. Electron and muon decay modes ($ell$ = e or$\mu$) are studied in the data collected with the CMS detector in 2017, in dedicated runs with reduced instantaneous luminosity. The data sets correspond to integrated luminosities of 298 $\pm$ 6 pb$^{-1}$ at 5.02 TeV and 206 $\pm$ 5 pb$^{-1}$ at 13 TeV. Measured values of the products of the total inclusive cross sections and the branching fractions at 5.02 TeV are $\sigma$(pp $\to$ W+X)$\mathcal{B}$(W $\to$$\ell\nu$) = 7300 $\pm$ 10 (stat) $\pm$ 60 (syst) $\pm$ 140 (lumi) pb, and $\sigma$(pp $\to$ Z+X)$\mathcal{B}$(Z $\to$$\ell^+\ell^-$) = 669 $\pm$ 2 (stat) $\pm$ 6 (syst) $\pm$ 13 (lumi) pb for the dilepton invariant mass in the range of 60-120 GeV. The corresponding results at 13 TeV are 20480 $\pm$ 10 (stat) $\pm$ 170 (syst) $\pm$ 470 (lumi) pb and 1952 $\pm$ 4 (stat) $\pm$ 18 (syst) $\pm$ 45 (lumi) pb. The measured values agree with cross section calculations at next-to-next-to-leading-order in perturbative quantum chromodynamics. Fiducial and total inclusive cross sections, ratios of cross sections of W$^+$ and W$^-$ production as well as inclusive W and Z boson production, and ratios of these measurements at 5.02 and 13 TeV are reported.
Distributions of $m_T$ in the $W^{+}$ signal selection for e final states for the pp collisions at $\sqrt{s}=$ 5TeV after the maximum likelihood fit. The EW backgrounds include the contributions from DY, $W\to\tau\nu$, and diboson processes.
Distributions of $m_T$ in the $W^{+}$ signal selection for mu final states for the pp collisions at $\sqrt{s}=$ 5TeV after the maximum likelihood fit. The EW backgrounds include the contributions from DY, $W\to\tau\nu$, and diboson processes.
Distributions of $m_T$ in the $W^{+}$ signal selection for e final states for the pp collisions at $\sqrt{s}=$ 13TeV after the maximum likelihood fit. The EW backgrounds include the contributions from DY, $W\to\tau\nu$, and diboson processes.
The Large Hadron Collider at CERN, delivering proton-proton collisions at much higher energies and far higher luminosities than previous machines, has enabled a comprehensive programme of measurements of the standard model (SM) processes by the CMS experiment. These unprecedented capabilities facilitate precise measurements of the properties of a wide array of processes, the most fundamental being cross sections. The discovery of the Higgs boson and the measurement of its mass became the keystone of the SM. Knowledge of the mass of the Higgs boson allows precision comparisons of the predictions of the SM with the corresponding measurements. These measurements span the range from one of the most copious SM processes, the total inelastic cross section for proton-proton interactions, to the rarest ones, such as Higgs boson pair production. They cover the production of Higgs bosons, top quarks, single and multibosons, and hadronic jets. Associated parameters, such as coupling constants, are also measured. These cross section measurements can be pictured as a descending stairway, on which the lowest steps represent the rarest processes allowed by the SM, some never seen before.
Cross sections of selected high-energy processes measured by the CMS experiment. Measurements performed at different LHC pp collision energies are marked by unique symbols and the coloured bands indicate the combined statistical and systematic uncertainty of the measurement. Grey bands indicate the uncertainty of the corresponding SM theory predictions. Shaded hashed bars indicate the excluded cross section region for a production process with the measured 95% CL upper limit on the process indicated by the solid line of the same colour.
Summary of production cross section measurements involving top quarks. Measurements performed at different LHC pp collision energies are marked by unique symbols and the coloured bands indicate the combined statistical and systematic uncertainty of the measurement. Grey bands indicate the uncertainty of the corresponding SM theory predictions. Shaded hashed bars indicate the excluded cross section region for a production process with the measured 95% C.L. upper limit on the process indicated by the solid line of the same colour.
Summary of measurements of jet cross sections and electroweak processes in association with jets. Measurements performed at different LHC pp collision energies are marked by unique symbols and the coloured bands indicate the combined statistical and systematic uncertainty of the measurement. Grey bands indicate the uncertainty of the corresponding SM theory predictions. Shaded hashed bars indicate the excluded cross section region for a production process with the measured 95% C.L. upper limit on the process indicated by the solid line of the same colour. Versions of these plots in pdf format with links to the publications can be found at https://cms-results.web.cern.ch/cms-results/public-results/publications/SMP-23-004/.
A combination of fifteen top quark mass measurements performed by the ATLAS and CMS experiments at the LHC is presented. The data sets used correspond to an integrated luminosity of up to 5 and 20$^{-1}$ of proton-proton collisions at center-of-mass energies of 7 and 8 TeV, respectively. The combination includes measurements in top quark pair events that exploit both the semileptonic and hadronic decays of the top quark, and a measurement using events enriched in single top quark production via the electroweak $t$-channel. The combination accounts for the correlations between measurements and achieves an improvement in the total uncertainty of 31% relative to the most precise input measurement. The result is $m_\mathrm{t}$ = 172.52 $\pm$ 0.14 (stat) $\pm$ 0.30 (syst) GeV, with a total uncertainty of 0.33 GeV.
Uncertainties on the $m_{t}$ values extracted in the LHC, ATLAS, and CMS combinations arising from the categories described in the text, sorted in order of decreasing value of the combined LHC uncertainty.
Multiplicity ($N_{\rm ch}$) distributions and transverse momentum ($p_{\rm T}$) spectra of inclusive primary charged particles in the kinematic range of $|\eta| < 0.8$ and 0.15 GeV/$c$$< p_{T} <$ 10 GeV/$c$ are reported for pp, p-Pb, Xe-Xe and Pb-Pb collisions at centre-of-mass energies per nucleon pair ranging from $\sqrt{s_{\rm NN}} = 2.76$ TeV up to $13$ TeV. A sequential two-dimensional unfolding procedure is used to extract the correlation between the transverse momentum of primary charged particles and the charged-particle multiplicity of the corresponding collision. This correlation sharply characterises important features of the final state of a collision and, therefore, can be used as a stringent test of theoretical models. The multiplicity distributions as well as the mean and standard deviation derived from the $p_{\rm T}$ spectra are compared to state-of-the-art model predictions. Providing these fundamental observables of bulk particle production consistently across a wide range of collision energies and system sizes can serve as an important input for tuning Monte Carlo event generators.
Charged-particle multiplicity distribution for pp collisions at 2.76 TeV.
Koba-Nielsen-Olesen scaled charged-particle multiplicity distribution for pp collisions at 2.76 TeV.
Charged-particle transverse momentum spectra as a function of charged-particle multiplicity for pp collisions at 2.76 TeV.
Two-particle transverse momentum differential correlators, recently measured in Pb--Pb collisions at energies available at the CERN Large Hadron Collider (LHC), provide an additional tool to gain insights into particle production mechanisms and infer transport properties, such as the ratio of shear viscosity to entropy density, of the medium created in Pb-Pb collisions. The longitudinal long-range correlations and the large azimuthal anisotropy measured at low transverse momenta in small collision systems, namely pp and p-Pb, at LHC energies resemble manifestations of collective behaviour. This suggests that locally equilibrated matter may be produced in these small collision systems, similar to what is observed in Pb-Pb collisions. In this work, the same two-particle transverse momentum differential correlators are exploited in pp and p-Pb collisions at $\sqrt{s} = 7$ TeV and $\sqrt{s_{\rm NN}} = 5.02$ TeV, respectively, to seek evidence for viscous effects. Specifically, the strength and shape of the correlators are studied as a function of the produced particle multiplicity to identify evidence for longitudinal broadening that might reveal the presence of viscous effects in these smaller systems. The measured correlators and their evolution from pp and p--Pb to Pb--Pb collisions are additionally compared to predictions from Monte Carlo event generators, and the potential presence of viscous effects is discussed.
Two-particle transverse momentum correlation $G_{2}^{\rm CD}$ for 0$-$5% multiplicity class pp collisions at $\sqrt{s}=7\;\text{TeV}$.
Two-particle transverse momentum correlation $G_{2}^{\rm CD}$ for 30$-$40% multiplicity class pp collisions at $\sqrt{s}=7\;\text{TeV}$.
Two-particle transverse momentum correlation $G_{2}^{\rm CD}$ for 70$-$80% multiplicity class pp collisions at $\sqrt{s}=7\;\text{TeV}$.
A combination of measurements of the inclusive top-quark pair production cross-section performed by ATLAS and CMS in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV at the LHC is presented. The cross-sections are obtained using top-quark pair decays with an opposite-charge electron-muon pair in the final state and with data corresponding to an integrated luminosity of about 5 fb$^{-1}$ at $\sqrt{s}=7$ TeV and about 20 fb$^{-1}$ at $\sqrt{s}=8$ TeV for each experiment. The combined cross-sections are determined to be $178.5 \pm 4.7$ pb at $\sqrt{s}=7$ TeV and $243.3^{+6.0}_{-5.9}$ pb at $\sqrt{s}=8$ TeV with a correlation of 0.41, using a reference top-quark mass value of 172.5 GeV. The ratio of the combined cross-sections is determined to be $R_{8/7}= 1.363\pm 0.032$. The combined measured cross-sections and their ratio agree well with theory calculations using several parton distribution function (PDF) sets. The values of the top-quark pole mass (with the strong coupling fixed at 0.118) and the strong coupling (with the top-quark pole mass fixed at 172.5 GeV) are extracted from the combined results by fitting a next-to-next-to-leading-order plus next-to-next-to-leading-log QCD prediction to the measurements. Using a version of the NNPDF3.1 PDF set containing no top-quark measurements, the results obtained are $m_t^\text{pole} = 173.4^{+1.8}_{-2.0}$ GeV and $\alpha_\text{s}(m_Z)= 0.1170^{+ 0.0021}_{-0.0018}$.
Full covariance matrix including all systematic uncertainties expressed as nuisance parameters. With the exception of the cross section parameters, all parameters were normalised to 1 before the fit. Therefore, the diagonal elements represent the constraint in quadrature.
Full covariance matrix including all systematic uncertainties expressed as nuisance parameters. With the exception of the cross section parameters, all parameters were normalised to 1 before the fit. Therefore, the diagonal elements represent the constraint in quadrature.
Angular correlations of heavy-flavour and charged particles in high-energy proton-proton collisions are sensitive to the production mechanisms of heavy quarks and to their fragmentation as well as hadronisation processes. The measurement of the azimuthal-correlation function of prompt D mesons with charged particles in proton-proton collisions at a centre-of-mass energy of $\sqrt{s} = 13$ TeV with the ALICE detector is reported, considering D$^{0}$, D$^{+}$, and D$^{*+}$ mesons in the transverse-momentum interval $3 < p_{\rm T} < 36$ GeV/$c$ at midrapidity ($|y| < 0.5$), and charged particles with $p_{\rm T} > 0.3$ GeV/$c$ and pseudorapidity $|\eta| < 0.8$. This measurement has an improved precision and provides an extended transverse-momentum coverage compared to previous ALICE measurements at lower energies. The study is also performed as a function of the charged-particle multiplicity, showing no modifications of the correlation function with multiplicity within uncertainties. The properties and the transverse-momentum evolution of the near- and away-side correlation peaks are studied and compared with predictions from various Monte Carlo event generators. Among those considered, PYTHIA8 and POWHEG+PYTHIA8 provide the best description of the measured observables. The obtained results can provide guidance on tuning the generators.
Comparison of the azimuthal-correlation distributions of D mesons (average of D$^{0}$, D$^{+}$, and D$^{*+}$) with $3 < p_{\rm T} < 5$ GeV/$c$ and charged particles with $0.3 < p_{\rm T} < 1$ GeV/$c$, in pp collisions at $\sqrt{s} = $5, 7, and 13 TeV, after baseline subtraction. Rapidity range for the D mesons is $|y^{\rm D}_{\rm cms}| < 0.5$. Correlations are integrated for $|\Delta\eta|=|\eta_{\rm ch}-\eta_{\rm D}| < 1$. The azimuthal-correlation distributions are reported in the range $0 < \Delta\varphi < \pi$.
Comparison of the azimuthal-correlation distributions of D mesons (average of D$^{0}$, D$^{+}$, and D$^{*+}$) with $8 < p_{\rm T} < 16$ GeV/$c$ and charged particles with $0.3 < p_{\rm T} < 1$ GeV/$c$, in pp collisions at $\sqrt{s} = $5, 7, and 13 TeV, after baseline subtraction. Rapidity range for the D mesons is $|y^{\rm D}_{\rm cms}| < 0.5$. Correlations are integrated for $|\Delta\eta|=|\eta_{\rm ch}-\eta_{\rm D}| < 1$. The azimuthal-correlation distributions are reported in the range $0 < \Delta\varphi < \pi$.
Comparison of the azimuthal-correlation distributions of D mesons (average of D$^{0}$, D$^{+}$, and D$^{*+}$) with $16 < p_{\rm T} < 24$ GeV/$c$ and charged particles with $0.3 < p_{\rm T} < 1$ GeV/$c$, in pp collisions at $\sqrt{s} = $5, 7, and 13 TeV, after baseline subtraction. Rapidity range for the D mesons is $|y^{\rm D}_{\rm cms}| < 0.5$. Correlations are integrated for $|\Delta\eta|=|\eta_{\rm ch}-\eta_{\rm D}| < 1$. The azimuthal-correlation distributions are reported in the range $0 < \Delta\varphi < \pi$.
This article reports on the inclusive production cross section of several quarkonium states, $\mathrm{J}/\psi$, $\psi {\rm (2S)}$, $\Upsilon\rm(1S)$, $\Upsilon\rm(2S)$, and $\Upsilon\rm(3S)$, measured with the ALICE detector at the LHC, in pp collisions at $\sqrt{s} = 5.02$ TeV. The analysis is performed in the dimuon decay channel at forward rapidity ($2.5 < y < 4$). The integrated cross sections and transverse-momentum ($p_{\rm T}$) and rapidity ($y$) differential cross sections for $\mathrm{J}/\psi$, $\psi {\rm (2S)}$, $\Upsilon\rm(1S)$, and the $\psi {\rm (2S)}$-to-$\mathrm{J}/\psi$ cross section ratios are presented. The integrated cross sections, assuming unpolarized quarkonia, are: $\sigma_{\mathrm{J}/\psi}$($p_{\rm T}<20$ GeV/c) = 5.88 $\pm$ 0.03 $\pm$ 0.34 $\mu$b, $\sigma_{\psi {\rm (2S)}}$($p_{\rm T}<12$ GeV/c) = 0.87 $\pm$ 0.06 $\pm$ 0.10 $\mu$b, $\sigma_{\Upsilon\rm(1S)}$($p_{\rm T}<15$ GeV/c) = 45.5 $\pm$ 3.9 $\pm$ 3.5 nb, $\sigma_{\Upsilon\rm(2S)}$($p_{\rm T}<15$ GeV/c) = 22.4 $\pm$ 3.2 $\pm$ 2.7 nb, and $\sigma_{\Upsilon\rm(3S)}$($p_{\rm T}<15$ GeV/c) = 4.9 $\pm$ 2.2 $\pm$ 1.0 nb, where the first (second) uncertainty is the statistical (systematic) one. For the first time, the cross sections of the three $\Upsilon$ states, as well as the $\psi {\rm (2S)}$ one as a function of $p_{\rm T}$ and $y$, are measured at $\sqrt{s} = 5.02$ TeV at forward rapidity. These measurements also significantly extend the $\mathrm{J}/\psi$$p_{\rm T}$ reach and supersede previously published results. A comparison with ALICE measurements in pp collisions at $\sqrt{s} = 2.76$, 7, 8, and 13 TeV is presented and the energy dependence of quarkonium production cross sections is discussed. Finally, the results are compared with the predictions from several production models.
Differential production cross sections of J/$\psi$ as a function of $p_{\rm T}$.
Differential production cross sections of J/$\psi$ as a function of rapidity.
Rapidity Differential production cross sections of J/$\psi$ in the range 0.3 $\leq$ p$_{\rm T}$ < 2 GeV/c
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