Combination of inclusive top-quark pair production cross-section measurements using ATLAS and CMS data at $\sqrt{s}= 7$ and 8 TeV

The ATLAS & CMS collaborations Aad, G. ; Abbott, B. ; Abbott, D.C. ; et al.
JHEP 07 (2023) 213, 2023.
Inspire Record 2088291 DOI 10.17182/hepdata.110250

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 $\alpha_\text{s}(m_Z)= 0.1170^{+ 0.0021}_{-0.0018}$.

2 data tables

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.


Charged-particle multiplicity distributions over a wide pseudorapidity range in proton-proton collisions at $\mathbf{\sqrt{s}=}$ 0.9, 7 and 8 TeV

The ALICE collaboration Acharya, S. ; Adamová, D. ; Adolfsson, J. ; et al.
Eur.Phys.J.C 77 (2017) 852, 2017.
Inspire Record 1614477 DOI 10.17182/hepdata.78802

We present the charged-particle multiplicity distributions over a wide pseudorapidity range ($-3.4<\eta<5.0$) for pp collisions at $\sqrt{s}=$ 0.9, 7, and 8 TeV at the LHC. Results are based on information from the Silicon Pixel Detector and the Forward Multiplicity Detector of ALICE, extending the pseudorapidity coverage of the earlier publications and the high-multiplicity reach. The measurements are compared to results from the CMS experiment and to PYTHIA, PHOJET and EPOS LHC event generators, as well as IP-Glasma calculations.

90 data tables

Multiplicity distribution in the pseudorapidity region -2.0 to 2.0 for NSD collisions at a centre-of-mass energy of 900 GeV.

Multiplicity distribution in the pseudorapidity region -2.4 to 2.4 for NSD collisions at a centre-of-mass energy of 900 GeV.

Multiplicity distribution in the pseudorapidity region -3.0 to 3.0 for NSD collisions at a centre-of-mass energy of 900 GeV.

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Test of lepton universality with $B^{0} \rightarrow K^{*0}\ell^{+}\ell^{-}$ decays

The LHCb collaboration Aaij, R. ; Adeva, B. ; Adinolfi, M. ; et al.
JHEP 08 (2017) 055, 2017.
Inspire Record 1599846 DOI 10.17182/hepdata.77815

A test of lepton universality, performed by measuring the ratio of the branching fractions of the $B^{0} \rightarrow K^{*0}\mu^{+}\mu^{-}$ and $B^{0} \rightarrow K^{*0}e^{+}e^{-}$ decays, $R_{K^{*0}}$, is presented. The $K^{*0}$ meson is reconstructed in the final state $K^{+}\pi^{-}$, which is required to have an invariant mass within 100$\mathrm{\,MeV}c^2$ of the known $K^{*}(892)^{0}$ mass. The analysis is performed using proton-proton collision data, corresponding to an integrated luminosity of about 3$\mathrm{\,fb}^{-1}$, collected by the LHCb experiment at centre-of-mass energies of 7 and 8$\mathrm{\,TeV}$. The ratio is measured in two regions of the dilepton invariant mass squared, $q^{2}$, to be \begin{eqnarray*} R_{K^{*0}} = \begin{cases} 0.66~^{+~0.11}_{-~0.07}\mathrm{\,(stat)} \pm 0.03\mathrm{\,(syst)} & \textrm{for } 0.045 < q^{2} < 1.1~\mathrm{\,GeV^2}c^4 \, , \\ 0.69~^{+~0.11}_{-~0.07}\mathrm{\,(stat)} \pm 0.05\mathrm{\,(syst)} & \textrm{for } 1.1\phantom{00} < q^{2} < 6.0~\mathrm{\,GeV^2}c^4 \, . \end{cases} \end{eqnarray*} The corresponding 95.4\% confidence level intervals are $[0.52, 0.89]$ and $[0.53, 0.94]$. The results, which represent the most precise measurements of $R_{K^{*0}}$ to date, are compatible with the Standard Model expectations at the level of 2.1--2.3 and 2.4--2.5 standard deviations in the two $q^{2}$ regions, respectively.

2 data tables

Distributions of the $R(K^{*0})$ delta log-likelihood, $-(\ln L - \ln L_{best})$, for the three trigger categories combined in the low-q2 bin ($0.045 < q^2 < 1.1$ GeV$^{2}/c^4$).

Distributions of the $R(K^{*0})$ delta log-likelihood, $-(\ln L - \ln L_{best})$, for the three trigger categories combined in the central-q2 bin ($1.1 < q^2 < 6.0$ GeV$^{2}/c^4$).


Mid-rapidity anti-baryon to baryon ratios in pp collisions at sqrt(s) = 0.9, 2.76 and 7 TeV measured by ALICE

The ALICE collaboration Abbas, E. ; Abelev, B. ; Adam, J. ; et al.
Eur.Phys.J.C 73 (2013) 2496, 2013.
Inspire Record 1232209 DOI 10.17182/hepdata.61965

The ratios of yields of anti-baryons to baryons probes the mechanisms of baryon-number transport. Results for $\bar{\rm p}/{\rm p}$, $\bar{\rm \Lambda}/{\rm \Lambda}$, $\rm\bar{\Xi}$$^{+}/{\rm \Xi}^{-}$ and $\rm\bar{\Omega}$$^{+}/{\rm \Omega}^{-}$ in pp collisions at $\sqrt{s} = 0.9$, 2.76 and 7 TeV, measured with the ALICE detector at the LHC, are reported. Within the experimental uncertainties and ranges covered by our measurement, these ratios are independent of rapidity, transverse momentum and multiplicity for all measured energies. The results are compared to expectations from event generators, such as PYTHIA and HIJING-B, that are used to model the particle production in pp collisions. The energy dependence of $\bar{\rm p}/{\rm p}$, $\bar{\rm \Lambda}/{\rm \Lambda}$, $\rm\bar{\Xi}$$^{+}/{\rm \Xi^{-}}$ and $\rm\bar{\Omega}$$^{+}/{\rm \Omega^{-}}$, reaching values compatible with unity for $\sqrt{s} = 7$ TeV, complement the earlier $\bar{\rm p}/{\rm p}$ measurement of ALICE. These dependencies can be described by exchanges with the Regge-trajectory intercept of $\alpha_{\rm {J}} \approx 0.5$, which are suppressed with increasing rapidity interval ${\rm \Delta} y$. Any significant contribution of an exchange not suppressed at large ${\rm \Delta} y$ (reached at LHC energies) is disfavoured.

20 data tables

The pbar/p ratio at sqrt(s) = 2.76 TeV as a function of pT.

The pbar/p ratio at sqrt(s) = 2.76 TeV as a function of rapidity.

The LambdaBar/Lambda ratio at sqrt(s) = 0.9 TeV as a function of pT.

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Measurement of the cross section for prompt isolated diphoton production using the full CDF Run II data sample

The CDF collaboration Aaltonen, T. ; Amerio, S. ; Amidei, D. ; et al.
Phys.Rev.Lett. 110 (2013) 101801, 2013.
Inspire Record 1207879 DOI 10.17182/hepdata.66020

This Letter reports a measurement of the cross section for producing pairs of central prompt isolated photons in proton-antiproton collisions at a total energy of 1.96 TeV using data corresponding to 9.5/fb integrated luminosity collected with the CDF II detector at the Fermilab Tevatron. The measured differential cross section is compared to three calculations derived from the theory of strong interactions. These include a prediction based on a leading order matrix element calculation merged with parton shower, a next-to-leading order, and a next-to-next-to-leading order calculation. The first and last calculations reproduce most aspects of the data, thus showing the importance of higher-order contributions for understanding the theory of strong interaction and improving measurements of the Higgs boson and searches for new phenomena in diphoton final states.

23 data tables

The measured differential cross sections for $M_{\gamma\gamma}$ , together with the predictions from the Sherpa and NNLO Monte Carlos.

The measured differential cross sections for $M_{\gamma\gamma}$ when $P_T > M_{\gamma\gamma}$ , together with the predictions from the Sherpa and NNLO Monte Carlos.

The measured differential cross sections for $M_{\gamma\gamma}$ when $P_T < M_{\gamma\gamma}$ , together with the predictions from the Sherpa and NNLO Monte Carlos.

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Neutral pion and $\eta$ meson production in proton-proton collisions at $\sqrt{s}=0.9$ TeV and $\sqrt{s}=7$ TeV

The ALICE collaboration Abelev, B. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
Phys.Lett.B 717 (2012) 162-172, 2012.
Inspire Record 1116147 DOI 10.17182/hepdata.58871

The first measurements of the invariant differential cross sections of inclusive $\pi^0$ and $\eta$ meson production at mid-rapidity in proton-proton collisions at $\sqrt{s}=0.9$ TeV and $\sqrt{s}=7$ TeV are reported. The $\pi^0$ measurement covers the ranges $0.4<p_T<7$ GeV/$c$ and $0.3<p_T<25$ GeV/$c$ for these two energies, respectively. The production of $\eta$ mesons was measured at $\sqrt{s}=7$ TeV in the range $0.4<p_T<15$ GeV/$c$. Next-to-Leading Order perturbative QCD calculations, which are consistent with the $\pi^0$ spectrum at $\sqrt{s}=0.9$ TeV, overestimate those of $\pi^0$ and $\eta$ mesons at $\sqrt{s}=7$ TeV, but agree with the measured $\eta/\pi^0$ ratio at $\sqrt{s}=7$ TeV.

4 data tables

The measured invariant differential section for inclusive PI0 production at a centre-of-mass energy of 7 TeV.

The measured invariant differential section for inclusive PI0 production at a centre-of-mass energy of 0.9 TeV.

The measured invariant differential section for inclusive ETA production at a centre-of-mass energy of 7 TeV.

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J/psi Production as a Function of Charged Particle Multiplicity in pp Collisions at sqrt{s} = 7 TeV

The ALICE collaboration Abelev, B. ; Adam, J. ; Adamova, D. ; et al.
Phys.Lett.B 712 (2012) 165-175, 2012.
Inspire Record 1088833 DOI 10.17182/hepdata.38163

The ALICE collaboration reports the measurement of the inclusive J/psi yield as a function of charged particle pseudorapidity density dN_{ch}/deta in pp collisions at sqrt{s} = 7 TeV at the LHC. J/psi particles are detected for p_t > 0, in the rapidity interval |y| < 0.9 via decay into e+e-, and in the interval 2.5 < y < 4.0 via decay into mu+mu- pairs. An approximately linear increase of the J/psi yields normalized to their event average (dN_{J/psi}/dy)/<dN_{J/psi}/dy> with (dN_{ch}/deta)/<dN_{ch}/deta> is observed in both rapidity ranges, where dN_{ch}/deta is measured within |eta| < 1 and p_t > 0. In the highest multiplicity interval with <dN_{ch}/deta(bin)> = 24.1, corresponding to four times the minimum bias multiplicity density, an enhancement relative to the minimum bias J/psi yield by a factor of about 5 at 2.5 < y < 4 (8 at |y| < 0.9) is observed.

2 data tables

The relative J/psi yield (dN_(j/psi)/dy)/<dN_(j/psi)/dy> in the di-electron channel as a function of the relative charged particle multiplicity density (dN_(ch)/deta)/<dN_(ch)/deta>.

The relative J/psi yield (dN_(j/psi)/dy)/<dN_(j/psi)/dy> in the di-muon channel as a function of the relative charged particle multiplicity density (dN_(ch)/deta)/<dN_(ch)/deta>.


Version 2
Measurement of charm production at central rapidity in proton-proton collisions at sqrt(s) = 7 TeV

The ALICE collaboration Abelev, B. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
JHEP 01 (2012) 128, 2012.
Inspire Record 944757 DOI 10.17182/hepdata.58524

The $p_{\rm T}$-differential inclusive production cross sections of the prompt charmed mesons $D^0$, $D^+$, and $D^{*+}$ in the rapidity range |y|<0.5 were measured in proton-proton collisions at $\sqrt{s} = 7$ TeV at the LHC using the ALICE detector. Reconstructing the decays $D^0\rightarrow K^-\pi^+$, $D^+\rightarrow K^-\pi^+\pi^+$, $D^{*+}\rightarrow D^0\pi^+$, and their charge conjugates, about 8,400 $D^0$, 2,900 $D^+$, and 2,600 $D^{*+}$ mesons with 1<$p_{\rm T}$<24 GeV/$c$ were counted, after selection cuts, in a data sample of 3.14x10$^8$ events collected with a minimum-bias trigger (integrated luminosity $L_{\rm int}$ = 5/nb). The results are described within uncertainties by predictions based on perturbative QCD.

8 data tables

Differential cross section for prompt D0 production.

Differential cross section for prompt D0 production.

Differential cross section for prompt D+ production.

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Light vector meson production in pp collisions at sqrt(s) = 7 TeV

The ALICE collaboration Abelev, B. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
Phys.Lett.B 710 (2012) 557-568, 2012.
Inspire Record 1080945 DOI 10.17182/hepdata.58629

The ALICE experiment has measured low-mass dimuon production in pp collisions at $\sqrt{s} = 7$ TeV in the dimuon rapidity region 2.5<y<4. The observed dimuon mass spectrum is described as a superposition of resonance decays ($\eta$, $\rho$, $\omega$, $\eta^{'}$, $\phi$) into muons and semi-leptonic decays of charmed mesons. The measured production cross sections for $\omega$ and $\phi$ are $\sigma_\omega$ (1<$p_{\rm T}$<5 GeV/$c$,2.5<y<4) = 5.28 $\pm$ 0.54 (stat) $\pm$ 0.50 (syst) mb and $\sigma_\phi$(1<$p_{\rm T}$<5 GeV/$c$,2.5<y<4)=0.940 $\pm$ 0.084 (stat) $\pm$ 0.078 (syst) mb. The differential cross sections $d^2\sigma/dy dp_{\rm T}$ are extracted as a function of $p_{\rm T}$ for $\omega$ and $\phi$. The ratio between the $\rho$ and $\omega$ cross section is obtained. Results for the $\phi$ are compared with other measurements at the same energy and with predictions by models.

5 data tables

Differential phi cross section from the di-muon channel as a function of transverse momentum, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one.

Differential omega cross section from the di-muon channel as a function of transverse momentum, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one.

Total phi cross section from the di-muon data. The first error is statistical, the second is a systematic error.

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Rapidity and transverse momentum dependence of inclusive J/psi production in pp collisions at sqrt(s) = 7 TeV

The ALICE collaboration Aamodt, K. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
Phys.Lett.B 704 (2011) 442-455, 2011.
Inspire Record 897764 DOI 10.17182/hepdata.57452

The ALICE experiment at the LHC has studied inclusive J/$\psi$ production at central and forward rapidities in pp collisions at $\sqrt{s} = 7$ TeV. In this Letter, we report on the first results obtained detecting the J/$\psi$ through its dilepton decay into $e^+e^-$ and $\mu^+\mu^-$ pairs in the rapidity range |y|<0.9 and 2.5<y<4, respectively, and with acceptance down to zero $p_{\rm T}$. In the dielectron channel the analysis was carried out on a data sample corresponding to an integrated luminosity $L_{\rm int}$ = 5.6 nb$^{-1}$ and the number of signal events is $N_{J/\psi}=352 \pm 32$ (stat.) $\pm$ 28 (syst.); the corresponding figures in the dimuon channel are $L_{\rm int}$ = 15.6 nb$^{-1}$ and $N_{J/\psi} = 1924 \pm 77$ (stat.) $\pm$ 144(syst.). The measured production cross sections are $\sigma_{J/\psi}$ (|y|<0.9) = 12.4 $\pm$ 1.1 (stat.) $\pm$ 1.8 (syst.) + 1.8 -2.7 (syst.pol.) $\mu$b and $\sigma_{J/\psi}$ (2.5<y<4) = 6.31 $\pm$ 0.25 (stat.) $\pm$ 0.76 (syst.) +0.95 -1.96 (syst.pol.) $\mu$b. The differential cross sections, in transverse momentum and rapidity, of the J/$\psi$ were also measured.

5 data tables

Double differential J/PSI cross section from the di-electron channel as a function of transverse momentum, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one. The last four columns are the errors considering. a +1 polarization in the Collins-Soper frame, a -1 polarization in the Collins-Soper frame, a +1 polarization in the Helicity frame and a -1 polarization in the Helicity frame, respectively.

Differential J/PSI cross section from the di-muon channel as a function of transverse momentum, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one. The last four columns are the errors (in MUB/GEV) considering a +1 polarization in the Collins-Soper frame, a -1 polarization in the Collins-Soper frame, a +1 polarization in the Helicity frame and a -1 polarization in the Helicity frame, respectively.

Differential J/PSI cross section from the di-electron and di-muon channel as a function of rapidity, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one. The last four columns are the errors (in MUB/GEV) considering. Data in the first point of this table updated from the erratum.

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