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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,207 records · Page 67
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DOE OSTI2016

Search for the Higgs boson produced in association with a W boson and decaying to four b-quarks via two spin-zero particles in pp collisions at 13 TeV with the ATLAS detector

This paper presents a dedicated search for exotic decays of the Higgs boson to a pair of new spin-zero particles, H→ aa, where the particle a decays to b-quarks and has a mass in the range of 20–60 GeV. The search is performed in events where the Higgs boson is produced in association with a W boson, giving rise to a signature of a lepton (electron or muon), missing transverse momentum, and multiple jets from b-quark decays. The analysis is based on the full dataset of pp collisions at $\sqrt{s}$=13 TeV recorded in 2015 by the ATLAS detector at the CERN Large Hadron Collider, corresponding to an integrated luminosity of 3.2 fb -1 . No significant excess of events above the Standard Model prediction is observed, and a 95% confidence-level upper limit is derived for the product of the production cross section for pp→ WH times the branching ratio for the decay H→ aa→ 4 b. The upper limit ranges from 6.2 pb for an a-boson mass m a = 20 GeV to 1.5 pb for m a =60 GeV.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2017

Measurement of the production cross section of a W boson in association with two b jets in pp collisions at $\sqrt{s} = 8{\,\mathrm{{TeV}}} $

The production cross section of a W boson in association with two b jets is measured using a sample of proton–proton collisions at $\sqrt{s} = 8{\,\mathrm{{TeV}}} $ collected by the CMS experiment at the CERN LHC. The data sample corresponds to an integrated luminosity of 19.8 $\,\text {fb}^\text {-1}$ . The W bosons are reconstructed via their leptonic decays, $\mathrm {W}\rightarrow \ell \nu $ , where $\ell =\mu $ or $\mathrm {e}$ . The fiducial region studied contains exactly one lepton with transverse momentum $p_{\mathrm {T}} ^{\ell }>30\,\mathrm{{GeV}} $ and pseudorapidity $|\eta ^{\ell } |<2.1$ , with exactly two b jets with $p_{\mathrm {T}} >25\,\mathrm{{GeV}} $ and $|\eta |<2.4$ and no other jets with $p_{\mathrm {T}} >25\,\mathrm{{GeV}} $ and $|\eta |<4.7$ . The cross section is measured to be $\sigma ( {{\mathrm {p}\mathrm {p}}} \rightarrow {\mathrm {W}} (\ell \nu )$ + ${\mathrm{{b}}\mathrm{{\overline{b}}}})= 0.64 \pm 0.03{\,\mathrm{{(stat)}}} \pm 0.10{\,\mathrm{{(syst)}}} \pm 0.06{\,\mathrm{{(theo)}}} \pm 0.02{\,\mathrm{{(lumi)}}}\,{\text {pb}}$ , in agreement with standard model predictions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2017

Measurement of the WZ production cross section in pp collisions at $\sqrt{s} = 7$ and 8 $\,\text{TeV}$ and search for anomalous triple gauge couplings at $\sqrt{s} = 8\,\text{TeV} $

The WZ production cross section is measured by the CMS experiment at the CERN LHC in proton–proton collision data samples corresponding to integrated luminosities of 4.9 $\,\text{fb}^{-1}$ collected at $\sqrt{s} = 7\,\text{TeV} $ , and 19.6 $\,\text{fb}^{-1}$ at $\sqrt{s} = 8\,\text{TeV} $ . The measurements are performed using the fully-leptonic WZ decay modes with electrons and muons in the final state. The measured cross sections for $71< m_{\mathrm{Z}} < 111\,\text{GeV} $ are $\sigma ({\mathrm{p}\mathrm{p}}\rightarrow {\mathrm{W}\mathrm{Z}},~\sqrt{s} = 7\,\text{TeV}) = 20.14 \pm 1.32\,\text{(stat)} \pm 0.38\,\text{(theo)} \pm 1.06\,\text{(exp)} \pm 0.44\,\text{(lumi)} $ $\,\text{pb}$ and $\sigma ({\mathrm{p}\mathrm{p}}\rightarrow {\mathrm{W}\mathrm{Z}},~\sqrt{s} = 8\,\text{TeV}) = 24.09 \pm 0.87\,\text{(stat)} \pm 0.80\,\text{(theo)} \pm 1.40\,\text{(exp)} \pm 0.63\,\text{(lumi)} $ $\,\text{pb}$ . Differential cross sections with respect to the $\mathrm{Z}$ boson $p_{\mathrm{T}}$ , the leading jet $p_{\mathrm{T}}$ , and the number of jets are obtained using the $\sqrt{s} = 8\,\text{TeV} $ data. The results are consistent with standard model predictions and constraints on anomalous triple gauge couplings are obtained.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2017

A search for new phenomena in pp collisions at $\sqrt{s} = 13\,\text {TeV} $ in final states with missing transverse momentum and at least one jet using the $\alpha _{\mathrm {T}}$ variable

A search for new phenomena is performed in final states containing one or more jets and an imbalance in transverse momentum in pp collisions at a centre-of-mass energy of 13 $\,\text {TeV}$ . The analysed data sample, recorded with the CMS detector at the CERN LHC, corresponds to an integrated luminosity of 2.3 $\,\text {fb}^{-1}$ . Several kinematic variables are employed to suppress the dominant background, multijet production, as well as to discriminate between other standard model and new physics processes. The search provides sensitivity to a broad range of new-physics models that yield a stable weakly interacting massive particle. The number of observed candidate events is found to agree with the expected contributions from standard model processes, and the result is interpreted in the mass parameter space of fourteen simplified supersymmetric models that assume the pair production of gluinos or squarks and a range of decay modes. For models that assume gluino pair production, masses up to 1575 and 975 $\,\text {GeV}$ are excluded for gluinos and neutralinos, respectively. For models involving the pair production of top squarks and compressed mass spectra, top squark masses up to 400 $\,\text {GeV}$ are excluded.

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DOE OSTI2017

Precision studies of observables in $p p \rightarrow W \rightarrow l\nu _l$ and $ pp \rightarrow \gamma ,Z \rightarrow l^+ l^-$ processes at the LHC

This report was prepared in the context of the LPCC "Electroweak Precision Measurements at the LHC WG" and summarizes the activity of a subgroup dedicated to the systematic comparison of public Monte Carlo codes, which describe the Drell-Yan processes at hadron colliders, in particular at the CERN Large Hadron Collider (LHC). This work represents an important step towards the definition of an accurate simulation framework necessary for very high-precision measurements of electroweak (EW) observables such as the $W$ boson mass and the weak mixing angle. All the codes considered in this report share at least next-to-leading-order (NLO) accuracy in the prediction of the total cross sections in an expansion either in the strong or in the EW coupling constant. The NLO fixed-order predictions have been scrutinized at the technical level, using exactly the same inputs, setup and perturbative accuracy, in order to quantify the level of agreement of different implementations of the same calculation. A dedicated comparison, again at the technical level, of three codes that reach next-to-next-to-leading-order (NNLO) accuracy in quantum chromodynamics (QCD) for the total cross section has also been performed. These fixed-order results are a well-defined reference that allows a classification of the impact of higher-order sets of radiative corrections. Several examples of higher-order effects due to the strong or the EW interaction are discussed in this common framework. Also the combination of QCD and EW corrections is discussed, together with the ambiguities that affect the final result, due to the choice of a specific combination recipe.

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DOE OSTI2017

Searches for pair production of third-generation squarks in $\sqrt{s}=13$ $\,\text {TeV}$ pp collisions

Searches are presented for direct production of top or bottom squark pairs in proton–proton collisions at the CERN LHC. Two searches, based on complementary techniques, are performed in all-jet final states that are characterized by a significant imbalance in transverse momentum. An additional search requires the presence of a charged lepton isolated from other activity in the event. The data were collected in 2015 at a centre-of-mass energy of 13 $\,\text {TeV}$ with the CMS detector and correspond to an integrated luminosity of 2.3 $\,\text {fb}^{-1}$ . No statistically significant excess of events is found beyond the expected contribution from standard model processes. Exclusion limits are set in the context of simplified models of top or bottom squark pair production. Models with top and bottom squark masses up to 830 and 890 $\,\text {GeV}$ , respectively, are probed for light neutralinos. For models with top squark masses of 675 $\,\text {GeV}$ , neutralino masses up to 260 $\,\text {GeV}$ are excluded at 95% confidence level.

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DOE OSTI2017

Measurements of the production cross section of a $Z$ boson in association with jets in pp collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

Measurements of the production cross section of a Z boson in association with jets in proton–proton collisions at √s = 13 TeV are presented, using data corresponding to an integrated luminosity of 3.16 fb –1 collected by the ATLAS experiment at the CERN Large Hadron Collider in 2015. Inclusive and differential cross sections are measured for events containing a Z boson decaying to electrons or muons and produced in association with up to seven jets with p T > 30 GeV and |y| < 2.5. Predictions from different Monte Carlo generators based on leading-order and next-to-leading-order matrix elements for up to two additional partons interfaced with parton shower and fixed-order predictions at next-to-leading order and next-to-next-to-leading order are compared with the measured cross sections. Good agreement within the uncertainties is observed for most of the modelled quantities, in particular with the generators which use next-to-leading-order matrix elements and the more recent next-to-next-to-leading-order fixed-order predictions.

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DOE OSTI2017

Measurement of meson resonance production in $\pi ^- + C$ interactions at SPS energies: The NA61/SHINE Collaboration

Here, we present measurements of $\rho^0$, $\omega$ and K$^{*0}$ spectra in $\pi^{-} + $C production interactions at 158 GeV/c and $\rho^0$ spectra at 350 GeV/c using the NA61/SHINE spectrometer at the CERN SPS. Spectra are presented as a function of the Feynman's variable $x_\text{F}$ in the range $0 < x_\text{F} < 1$ and $0 < x_\text{F} < 0.5$ for 158 GeV/c and 350 GeV/c respectively. Furthermore, we show comparisons with previous measurements and predictions of several hadronic interaction models. Our measurements are essential for a better understanding of hadronic shower development and for improving the modeling of cosmic ray air showers.

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DOE OSTI2017

Search for dark matter produced in association with heavy-flavor quark pairs in proton-proton collisions at $\sqrt{s}=13$ TeV

A search is presented for an excess of events with heavy-flavor quark pairs ( ${t}\overline{{t}} $ and ${b} \overline{{b}} $ ) and a large imbalance in transverse momentum in data from proton–proton collisions at a center-of-mass energy of 13 $\,\text{TeV}$ . The data correspond to an integrated luminosity of 2.2 $\,\text{fb}^{-1}$ collected with the CMS detector at the CERN LHC. No deviations are observed with respect to standard model predictions. The results are used in the first interpretation of dark matter production in ${t}\overline{{t}} $ and ${b} \overline{{b}} $ final states in a simplified model. This analysis is also the first to perform a statistical combination of searches for dark matter produced with different heavy-flavor final states. The combination provides exclusions that are stronger than those achieved with individual heavy-flavor final states.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2018

Measurement of associated Z + charm production in proton-proton collisions at $\sqrt{s} = $ 8 TeV

A study of the associated production of a $\mathrm{Z} $ boson and a charm quark jet ( $\mathrm{Z} + \mathrm{c} $ ), and a comparison to production with a $\mathrm{b} $ quark jet ( $\mathrm{Z} + \mathrm{b} $ ), in $\mathrm {p}\mathrm {p}$ collisions at a centre-of-mass energy of 8 $\,\text {TeV}$ are presented. The analysis uses a data sample corresponding to an integrated luminosity of 19.7 $\,\text {fb}^{-1}$ , collected with the CMS detector at the CERN LHC. The $\mathrm{Z} $ boson candidates are identified through their decays into pairs of electrons or muons. Jets originating from heavy flavour quarks are identified using semileptonic decays of $\mathrm{c} $ or $\mathrm{b} $ flavoured hadrons and hadronic decays of charm hadrons. The measurements are performed in the kinematic region with two leptons with $p_{\mathrm {T}} ^{\ell } > 20\,\text {GeV} $ , ${|\eta ^{\ell }|} < 2.1$ , $71< m_{\ell \ell } < 111\,\text {GeV} $ , and heavy flavour jets with $p_{\mathrm {T}} ^{\text {jet}} > 25\,\text {GeV} $ and ${|\eta ^{ \text {jet}}|} < 2.5$ . The $\mathrm{Z} + \mathrm{c} $ production cross section is measured to be $\sigma (\mathrm {p}\mathrm {p}\rightarrow \mathrm{Z} + \mathrm{c} + X) \mathcal {B}(\mathrm{Z} \rightarrow \ell ^+\ell ^-) = 8.8 \pm 0.5\,\text {(stat)} \pm 0.6\,\text {(syst)} \,\text {pb} $ . The ratio of the $\mathrm{Z} + \mathrm{c} $ and $\mathrm{Z} + \mathrm{b} $ production cross sections is measured to be $\sigma (\mathrm {p}\mathrm {p}\rightarrow \mathrm{Z} + \mathrm{c} + X)/\sigma (\mathrm {p}\mathrm {p}\rightarrow \mathrm{Z} + \mathrm{b} + X) = 2.0 \pm 0.2\,\text {(stat)} \pm 0.2\,\text {(syst)} $ . The $\mathrm{Z} + \mathrm{c} $ production cross section and the cross section ratio are also measured as a function of the transverse momentum of the $\mathrm{Z} $ boson and of the heavy flavour jet. The measurements are compared with theoretical predictions.

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DOE OSTI2018

Neutral pion and $$\eta $$η meson production in p–Pb collisions at $$\sqrt{s_{\mathrm{NN}}}$$sNN = 5.02 TeV

Neutral pion and η meson invariant differential yields were measured in non-single diffractive p–Pb collisions at $ \sqrt{s}=5.02 $ TeV with the ALICE experiment at the CERN LHC. The analysis combines results from three complementary photon measurements, utilizing the PHOS and EMCal calorimeters and the Photon Conversion Method. The invariant differential yields of π0 and η meson inclusive production are measured near mid-rapidity in a broad transverse momentum range of 0.3 4 GeV / c at 0.483 ± 0. 015 stat± 0. 015 sys. A deviation from mT scaling is observed for pT< 2 GeV / c. The measured η/ π 0 ratio is consistent with previous measurements from proton-nucleus and pp collisions over the full pT range. The measured η/ π 0 ratio at high pT also agrees within uncertainties with measurements from nucleus–nucleus collisions. The π 0 and η yields in p–Pb relative to the scaled pp interpolated reference, RpPb, are presented for 0.3 < pT< 20 GeV / c and 0.7 < pT< 20 GeV / c, respectively. The results are compared with theoretical model calculations. The values of RpPb are consistent with unity for transverse momenta above 2 GeV / c. These results support the interpretation that the suppressed yield of neutral mesons measured in Pb–Pb collisions at LHC energies is due to parton energy loss in the hot QCD medium.

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DOE OSTI2018

Measurement of the top quark mass with lepton+jets final states using $\mathrm {p}$$ $$\mathrm {p}$ collisions at $\sqrt{s}=13\,\text {TeV} $

The mass of the top quark is measured using a sample of $\mathrm{t\overline{t}}$ events containing one isolated muon or electron and at least four jets in the final state, collected by the CMS detector using proton-proton collisions at $\sqrt{s}=$ 13 TeV at the CERN LHC. The events are selected from data corresponding to an integrated luminosity of 35.9 fb$^{-1}$. For each event the mass is reconstructed from a kinematic fit of the decay products to a \ttbar hypothesis. Using the ideogram method, the top quark mass is determined simultaneously with an overall jet energy scale factor (JSF), constrained by the mass of the W boson in $\mathrm{q\overline{q}'}$ decays. The measurement is calibrated on samples simulated at next-to-leading order matched to a leading-order parton shower. The top quark mass is found to be 172.25$\pm$0.08 (stat+JSF)$\pm$0.62 (syst) GeV. The dependence of this result on the kinematic properties of the event is studied and compared to predictions of different models of $\mathrm{t\overline{t}}$ production, and no indications of a bias in the measurements are observed.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

Measurements of W and Z boson production in pp collisions at $$\sqrt{s}=5.02$$ s = 5.02 TeV with the ATLAS detector

Measurements of fiducial integrated and differential cross sections for inclusive W + , W - and Z boson production are reported. They are based on 25.0±0.5pb -1 of pp collision data at √s=5.02 TeV collected with the ATLAS detector at the CERN Large Hadron Collider. Electron and muon decay channels are analysed, and the combined W + , W - and Z integrated cross sections are found to be σ W+ =2266±9 (stat)±29 (syst)±43 (lumi) pb, σ W- =1401±7 (stat)±18 (syst)±27 (lumi) pb, and σ Z =374.5±3.4 (stat)±3.6 (syst)±7.0 (lumi) pb, in good agreement with next-to-next-to-leading-order QCD cross-section calculations. These measurements serve as references for Pb+Pb interactions at the LHC at √sNN=5.02 TeV.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

Search for a heavy resonance decaying to a top quark and a vector-like top quark in the lepton + jets final state in pp collisions at $\sqrt{s} = 13\,\text {TeV} $

Here a search is presented for a heavy spin-1 resonance $\mathrm {Z}'$ decaying to a top quark and a vector-like top quark partner $\text {T} $ in the lepton + jets final state. The search is performed using a data set of $\mathrm {p}$ $\mathrm {p}$ collisions at a centre-of-mass energy of 13 $\,\text {TeV}$ corresponding to an integrated luminosity of $35.9{\,\text {fb}^{-1}} $ as recorded by the CMS experiment at the CERN LHC in the year 2016. The analysis is optimised for final states arising from the $\text {T} $ decay modes to a top quark and a Higgs or $\mathrm {Z}$ boson ( $\text {T} \rightarrow \mathrm {H} \mathrm {t}, \mathrm {Z} \mathrm {t}$ ). The event selection makes use of resolved and merged top quark decay products, as well as decays of boosted Higgs bosons and $\mathrm {Z}$ and $\mathrm {W}$ bosons using jet substructure techniques. No significant deviation from the standard model background expectation is observed. Exclusion limits on the product of the cross section and branching fraction for $\mathrm {Z}'\rightarrow \mathrm {t}\text {T}, \text {T} \rightarrow \mathrm {H} \mathrm {t}, \mathrm {Z} \mathrm {t}, \mathrm {W}\mathrm {b}$ are presented for various combinations of the $\mathrm {Z}'$ resonance mass and the vector-like $\text {T} $ quark mass. These results represent the most stringent limits to date for the decay mode $\mathrm {Z}'\rightarrow \mathrm {t}\text {T} \rightarrow \mathrm {t}\mathrm {H} \mathrm {t}$ . In a benchmark model with extra dimensions, invoking a heavy spin-1 resonance $\mathrm {G}^* $ , masses of the $\mathrm {G}^* $ between 1.5 and 2.3 $\,\text {TeV}$ and between 2.0 and 2.4 $\,\text {TeV}$ are excluded for $\text {T} $ masses of 1.2 and 1.5 $\,\text {TeV}$ , respectively.

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DOE OSTI2019

Relative particle yield fluctuations in Pb-Pb collisions at $\sqrt{s_\mathrm{{NN}}} =2.76\hbox { TeV}$

First results on K/$\pi$, p/$\pi$ and K/p fluctuations are obtained with the ALICE detector at the CERN LHC as a function of centrality in Pb-Pb collisions at $\sqrt{s_\mathrm{{NN}}} =2.76\hbox { TeV}$. The observable ν dyn , which is defined in terms of the moments of particle multiplicity distributions, is used to quantify the magnitude of dynamical fluctuations of relative particle yields and also provides insight into the correlation between particle pairs. This study is based on a novel experimental technique, called the Identity Method, which allows one to measure the moments of multiplicity distributions in case of incomplete particle identification. The results for p/$\pi$ show a change of sign in ν dyn from positive to negative towards more peripheral collisions. For central collisions, the results follow the smooth trend of the data at lower energies and ν dyn exhibits a change in sign for p/$\pi$ and K/p.

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DOE OSTI2019

Measurement of associated production of a $\mathrm {W}$ boson and a charm quark in proton–proton collisions at $\sqrt{s} = 13\,\text {Te}\text {V} $

Measurements are presented of associated production of a W boson and a charm quark (W+c) in proton-proton collisions at a center-of-mass energy of 13 TeV. The data correspond to an integrated luminosity of 35.7 fb$^{-1}$ collected by the CMS experiment at the CERN LHC. The W bosons are identified by their decay into a muon and a neutrino. The charm quarks are tagged via the full reconstruction of D$^*$(2010)$^\pm$ mesons that decay via D$^*$(2010)$^\pm \to$ D$^0 + \pi^\pm \to $K$^{\mp} + \pi^\pm + \pi^\pm$. A cross section is measured in the fiducial region defined by the muon transverse momentum $p_{T}^{\mu} >$ 26 GeV, muon pseudorapidity $|\eta^{\mu}| <$ 2.4, and charm quark transverse momentum $p_{T}^{c} >$ 5 GeV. The inclusive cross section for this kinematic range is $\sigma$(W+c)$=$1026$\pm $31 (stat)$\substack{+76\\-72}$ (syst) pb. The cross section is also measured differentially as a function of the pseudorapidity of the muon from the W boson decay. These measurements are compared with theoretical predictions and are used to probe the strange quark content of the proton.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

Search for vector-like quarks in events with two oppositely charged leptons and jets in proton–proton collisions at $\sqrt{s} = 13\,\text {Te}\text {V} $

A search for the pair production of heavy vector-like partners $\mathrm {T}$ and $\mathrm {B}$ of the top and bottom quarks has been performed by the CMS experiment at the CERN LHC using proton–proton collisions at $\sqrt{s} = 13\,\text {Te}\text {V} $ . The data sample was collected in 2016 and corresponds to an integrated luminosity of 35.9 $\,\text {fb}^{-1}$ . Final states studied for $\mathrm {T} \overline{\mathrm {T}} $ production include those where one of the $\mathrm {T}$ quarks decays via $\mathrm {T} \rightarrow \mathrm {t}\mathrm {Z}$ and the other via $\mathrm {T} \rightarrow \mathrm {b}\mathrm {W}$ , $\mathrm {t}\mathrm {Z}$ , or $\mathrm {t}\mathrm {H} $ , where $\mathrm {H}$ is a Higgs boson. For the $\mathrm {B} \overline{\mathrm {B}} $ case, final states include those where one of the $\mathrm {B}$ quarks decays via $\mathrm {B} \rightarrow \mathrm {b}\mathrm {Z}$ and the other $\mathrm {B} \rightarrow \mathrm {t}\mathrm {W}$ , $\mathrm {b}\mathrm {Z}$ , or $\mathrm {b}\mathrm {H} $ . Events with two oppositely charged electrons or muons, consistent with coming from the decay of a $\mathrm {Z}$ boson, and jets are investigated. The number of observed events is consistent with standard model background estimations. Lower limits at 95% confidence level are placed on the masses of the $\mathrm {T}$ and $\mathrm {B}$ quarks for a range of branching fractions. Assuming 100% branching fractions for $\mathrm {T} \rightarrow \mathrm {t}\mathrm {Z}$ , and $\mathrm {B} \rightarrow \mathrm {b}\mathrm {Z}$ , $\mathrm {T}$ and $\mathrm {B}$ quark mass values below 1280 and 1130 $\,\text {Ge}\text {V}$ , respectively, are excluded.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

Measurement of the ${\mathrm {t}\overline{\mathrm {t}}}$ production cross section, the top quark mass, and the strong coupling constant using dilepton events in pp collisions at $\sqrt{s}=13\,\text {Te}\text {V} $

A measurement of the top quark-antiquark pair production cross section $\sigma_{\mathrm{t\overline{t}}}$ in proton-proton collisions at a centre-of-mass energy of 13 TeV is presented. The data correspond to an integrated luminosity of 35.9 fb$^{-1}$, recorded by the CMS experiment at the CERN LHC in 2016. Dilepton events (e$^\pm\mu^\mp$, $\mu^+\mu^-$, e$^+$e$^-$) are selected and the cross section is measured from a likelihood fit. For a top quark mass parameter in the simulation of $m^{\mathrm{MC}}_{\mathrm{t}} =$ 172.5 GeV the fit yields a measured cross section $\sigma_{\mathrm{t\overline{t}}} =$ 803 $\pm$ 2 (stat) $\pm$ 25 (syst) $\pm$ 20 (lumi) pb, in agreement with the expectation from the standard model calculation at next-to-next-to-leading order. A simultaneous fit of the cross section and the top quark mass parameter in the POWHEG simulation is performed. The measured value of $m^{\mathrm{MC}}_{\mathrm{t}} =$ 172.33 $\pm$ 0.14 (stat) $^{+0.66}_{-0.72}$ (syst) GeV is in good agreement with previous measurements. The resulting cross section is used, together with the theoretical prediction, to determine the top quark mass and to extract a value of the strong coupling constant with different sets of parton distribution functions.

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