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The original article can be found online at https://doi.org/10.1140/epjc/s10052-018-6242-x. J. C (2018) 78:789 https://doi.org/10.1140/epjc/s10052-018-6242-x In this article the author name Luigi Calligaris was incorrectly written as A. Calligaris. [Extracted from the article]

The original article can be found online at https://doi.org/10.1140/epjc/s10052-018-6332-9. J. C (2018) 78:891 https://doi.org/10.1140/epjc/s10052-018-6332-9 In this article the author name Luigi Calligaris was incorrectly written as A. Calligaris. [Extracted from the article]

The original article can be found online at https://doi.org/10.1140/epjc/s10052-019-6774-8. Erratum to: Measurement of exclusive photoproduction from protons in pPb collisions at sNN=5.02TeV J. C (2019) 79:277 https://doi.org/10.1140/epjc/s10052-019-6774-8 In this article the author name Luigi Calligaris was incorrectly written as A. Calligaris. [Extracted from the article]

A Correction to this paper has been published: https://doi.org/10.1140/epjc/s10052-020-08562-y [ABSTRACT FROM AUTHOR]

Measurements are presented of the single-diffractive dijet cross section and the diffractive cross section as a function of the proton fractional momentum loss ξ and the four-momentum transfer squared t. Both processes p p → p X and p p → X p , i.e. with the proton scattering to either side of the interaction point, are measured, where X includes at least two jets; the results of the two processes are averaged. The analyses are based on data collected simultaneously with the CMS and TOTEM detectors at the LHC in proton–proton collisions at s = 8 Te during a dedicated run with β ∗ = 90 m at low instantaneous luminosity and correspond to an integrated luminosity of 37.5 nb - 1 . The single-diffractive dijet cross section σ jj p X , in the kinematic region ξ < 0.1 , 0.03 < | t | < 1 Ge 2 , with at least two jets with transverse momentum p T > 40 Ge , and pseudorapidity | η | < 4.4 , is 21.7 ± 0.9 (stat) - 3.3 + 3.0 (syst) ± 0.9 (lumi) nb . The ratio of the single-diffractive to inclusive dijet yields, normalised per unit of ξ , is presented as a function of x, the longitudinal momentum fraction of the proton carried by the struck parton. The ratio in the kinematic region defined above, for x values in the range - 2.9 ≤ log 10 x ≤ - 1.6 , is R = (σ jj p X / Δ ξ) / σ jj = 0.025 ± 0.001 (stat) ± 0.003 (syst) , where σ jj p X and σ jj are the single-diffractive and inclusive dijet cross sections, respectively. The results are compared with predictions from models of diffractive and nondiffractive interactions. Monte Carlo predictions based on the HERA diffractive parton distribution functions agree well with the data when corrected for the effect of soft rescattering between the spectator partons. [ABSTRACT FROM AUTHOR]

Normalised multi-differential cross sections for top quark pair ( t t ¯ ) production are measured in proton-proton collisions at a centre-of-mass energy of 13 TeV using events containing two oppositely charged leptons. The analysed data were recorded with the CMS detector in 2016 and correspond to an integrated luminosity of 35.9 fb - 1 . The double-differential t t ¯ cross section is measured as a function of the kinematic properties of the top quark and of the t t ¯ system at parton level in the full phase space. A triple-differential measurement is performed as a function of the invariant mass and rapidity of the t t ¯ system and the multiplicity of additional jets at particle level. The data are compared to predictions of Monte Carlo event generators that complement next-to-leading-order (NLO) quantum chromodynamics (QCD) calculations with parton showers. Together with a fixed-order NLO QCD calculation, the triple-differential measurement is used to extract values of the strong coupling strength α S and the top quark pole mass ( m t pole ) using several sets of parton distribution functions (PDFs). The measurement of m t pole exploits the sensitivity of the t t ¯ invariant mass distribution to m t pole near the production threshold. Furthermore, a simultaneous fit of the PDFs, α S , and m t pole is performed at NLO, demonstrating that the new data have significant impact on the gluon PDF, and at the same time allow an accurate determination of α S and m t pole . The values α S (m Z) = 0.1135 - 0.0017 + 0.0021 and m t pole = 170.5 ± 0.8 GeV are extracted, which account for experimental and theoretical uncertainties, the latter being estimated from NLO scale variations. Possible effects from Coulomb and soft-gluon resummation near the t t ¯ production threshold are neglected in these parameter extractions. A rough estimate of these effects indicates an expected correction of m t pole of the order of + 1 GeV , which can be regarded as additional theoretical uncertainty in the current m t pole extraction. [ABSTRACT FROM AUTHOR]

Events with no charged particles produced between the two leading jets are studied in proton-proton collisions at [ABSTRACT FROM AUTHOR]

Bose-Einstein correlations of charged hadrons are measured over a broad multiplicity range, from a few particles up to about 250 reconstructed charged hadrons in proton-proton collisions at s = 13 TeV. The results are based on data collected using the CMS detector at the LHC during runs with a special low-pileup configuration. Three analysis techniques with different degrees of dependence on simulations are used to remove the non-Bose-Einstein background from the correlation functions. All three methods give consistent results. The measured lengths of homogeneity are studied as functions of particle multiplicity as well as average pair transverse momentum and mass. The results are compared with data from both CMS and ATLAS at s = 7 TeV, as well as with theoretical predictions. [ABSTRACT FROM AUTHOR]

A measurement is presented of electroweak (EW) production of a W boson in association with two jets in proton–proton collisions at s = 13 Te . The data sample was recorded by the CMS Collaboration at the LHC and corresponds to an integrated luminosity of 35.9 fb - 1 . The measurement is performed for the ℓ ν jj final state (with ℓ ν indicating a lepton–neutrino pair, and j representing the quarks produced in the hard interaction) in a kinematic region defined by invariant mass m jj > 120 Ge and transverse momenta p T j > 25 Ge . The cross section of the process is measured in the electron and muon channels yielding σ EW (W jj) = 6.23 ± 0.12 (stat) ± 0.61 (syst) pb per channel, in agreement with leading-order standard model predictions. The additional hadronic activity of events in a signal-enriched region is studied, and the measurements are compared with predictions. The final state is also used to perform a search for anomalous trilinear gauge couplings. Limits on anomalous trilinear gauge couplings associated with dimension-six operators are given in the framework of an effective field theory. The corresponding 95% confidence level intervals are - 2.3 < c W W W / Λ 2 < 2.5 Te - 2 , - 8.8 < c W / Λ 2 < 16 Te - 2 , and - 45 < c B / Λ 2 < 46 Te - 2 . These results are combined with the CMS EW Zjj analysis, yielding the constraint on the c W W W coupling: - 1.8 < c W W W / Λ 2 < 2.0 Te - 2 . [ABSTRACT FROM AUTHOR]

New sets of CMS underlying-event parameters ("tunes") are presented for the pythia8 event generator. These tunes use the NNPDF3.1 parton distribution functions (PDFs) at leading (LO), next-to-leading (NLO), or next-to-next-to-leading (NNLO) orders in perturbative quantum chromodynamics, and the strong coupling evolution at LO or NLO. Measurements of charged-particle multiplicity and transverse momentum densities at various hadron collision energies are fit simultaneously to determine the parameters of the tunes. Comparisons of the predictions of the new tunes are provided for observables sensitive to the event shapes at LEP, global underlying event, soft multiparton interactions, and double-parton scattering contributions. In addition, comparisons are made for observables measured in various specific processes, such as multijet, Drell–Yan, and top quark-antiquark pair production including jet substructure observables. The simulation of the underlying event provided by the new tunes is interfaced to a higher-order matrix-element calculation. For the first time, predictions from pythia8 obtained with tunes based on NLO or NNLO PDFs are shown to reliably describe minimum-bias and underlying-event data with a similar level of agreement to predictions from tunes using LO PDF sets. [ABSTRACT FROM AUTHOR]

Measurements of the differential cross section for the Drell-Yan process, based on proton-proton collision data at a centre-of-mass energy of 13 TeV, collected by the CMS experiment, are presented. The data correspond to an integrated luminosity of 2.8 (2.3) fb−1 in the dimuon (dielectron) channel. The total and fiducial cross section measurements are presented as a function of dilepton invariant mass in the range 15 to 3000 GeV, and compared with the perturbative predictions of the standard model. The measured differential cross sections are in good agreement with the theoretical calculations. [ABSTRACT FROM AUTHOR]

Measurements are presented of the triple-differential cross section for inclusive isolated-photon+jet events in p p collisions at s = 8 TeV as a function of photon transverse momentum ( p T γ ), photon pseudorapidity ( η γ ), and jet pseudorapidity ( η jet ). The data correspond to an integrated luminosity of 19.7 fb - 1 that probe a broad range of the available phase space, for | η γ | < 1.44 and 1.57 < | η γ | < 2.50 , | η jet | < 2.5 , 40 < p T γ < 1000 GeV , and jet transverse momentum, p T jet , > 25 GeV . The measurements are compared to next-to-leading order perturbative quantum chromodynamics calculations, which reproduce the data within uncertainties. [ABSTRACT FROM AUTHOR]

A search for new physics in top quark production is performed in proton-proton collisions at 13 TeV . The data set corresponds to an integrated luminosity of 35.9 fb - 1 collected in 2016 with the CMS detector. Events with two opposite-sign isolated leptons (electrons or muons), and b quark jets in the final state are selected. The search is sensitive to new physics in top quark pair production and in single top quark production in association with a W boson. No significant deviation from the standard model expectation is observed. Results are interpreted in the framework of effective field theory and constraints on the relevant effective couplings are set, one at a time, using a dedicated multivariate analysis. This analysis differs from previous searches for new physics in the top quark sector by explicitly separating t W from t t ¯ events and exploiting the specific sensitivity of the t W process to new physics. [ABSTRACT FROM AUTHOR]

A measurement is performed of the cross section of top quark pair production in association with a W or Z boson using proton-proton collisions at a center-of-mass energy of 13 TeV at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb-1 , collected by the CMS experiment in 2016. The measurement is performed in the same-sign dilepton, three- and four-lepton final states. The production cross sections are measured to be σ(tt¯W) = 0.77+0.12-0.11(stat)+0.13-0.12(syst) pb and σ(tt ¯Z) = 0.99+0.09-0.08(stat)+0.12-0.10(syst) pb. The expected (observed) signal significance for the tt ¯W production in same-sign dilepton channel is found to be 4.5 (5.3) standard deviations, while for the tt ¯Z production in threeand four-lepton channels both the expected and the observed significances are found to be in excess of 5 standard deviations. The results are in agreement with the standard model predictions and are used to constrain the Wilson coefficients for eight dimension-six operators describing new interactions that would modify tt ¯W and tt ¯Z production. [ABSTRACT FROM AUTHOR]

A search is presented for long-lived charged particles that decay within the CMS detector and produce the signature of a disappearing track. A disappearing track is an isolated track with missing hits in the outer layers of the silicon tracker, little or no energy in associated calorimeter deposits, and no associated hits in the muon detectors. This search uses data collected with the CMS detector in 2015 and 2016 from protonproton collisions at a center-of-mass energy of 13 TeV at the LHC, corresponding to an integrated luminosity of 38.4 fb-1 . The results of the search are interpreted in the context of the anomaly-mediated supersymmetry breaking model. The data are consistent with the background-only hypothesis. Limits are set on the product of the cross section for direct production of charginos and their branching fraction to a neutralino and a pion, as a function of the chargino mass and lifetime. At 95% confidence level, charginos with masses below 715 (695) GeV are excluded for a lifetime of 3 (7) ns, as are charginos with lifetimes from 0.5 to 60 ns for a mass of 505 GeV. These are the most stringent limits using a disappearing track signature on this signal model for chargino lifetimes above ≈0.7 ns. [ABSTRACT FROM AUTHOR]

A search is presented for a heavy resonance decaying into either a pair of Z bosons or a Z boson and a W boson (ZZ or WZ), with a Z boson decaying into a pair of neutrinos and the other boson decaying hadronically into two collimated quarks that are reconstructed as a highly energetic large-cone jet. The search is performed using the data collected with the CMS detector at the CERN LHC during 2016 in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to a total integrated luminosity of 35.9 fb-1. No excess is observed in data with regard to background expectations. Results are interpreted in scenarios of physics beyond the standard model. Limits at 95% confidence level on production cross sections are set at 0.9 fb (63 fb) for spin-1 W' bosons, included in the heavy vector triplet model, with mass 4.0 TeV (1.0 TeV), and at 0.5 fb (40 fb) for spin-2 bulk gravitons with mass 4.0 TeV (1.0 TeV). Lower limits are set on the masses of W' bosons in the context of two versions of the heavy vector triplet model of 3.1TeV and 3.4 TeV, respectively [ABSTRACT FROM AUTHOR]

This paper presents a measurement of the underlying event activity in proton-proton collisions at a center-of-mass energy of 13 TeV, performed using inclusive Z boson production events collected with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 2.1 fb-1. The underlying event activity is quantified in terms of the charged particle multiplicity, as well as of the scalar sum of the charged particles' transverse momenta in different topological regions defined with respect to the Z boson direction. The distributions are unfolded to the stable particle level and compared with predictions from various Monte Carlo event generators, as well as with similar CDF and CMS measurements at center-of-mass energies of 1.96 and 7 TeV respectively. [ABSTRACT FROM AUTHOR]