Measurement of the production cross section for a W boson in association with a charm quark in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Eur.Phys.J.C 84 (2024) 27, 2024.
Inspire Record 2685711 DOI 10.17182/hepdata.141611

The strange quark content of the proton is probed through the measurement of the production cross section for a W boson and a charm (c) quark in proton-proton collisions at a center-of-mass energy of 13 TeV. The analysis uses a data sample corresponding to a total integrated luminosity of 138 fb$^{-1}$ collected with the CMS detector at the LHC. The W bosons are identified through their leptonic decays to an electron or a muon, and a neutrino. Charm jets are tagged using the presence of a muon or a secondary vertex inside the jet. The W+c production cross section and the cross section ratio $R^\pm_\text{c}$ = $\sigma$(W$^+$+$\bar{\text{c}}$) / $\sigma$(W$^-$+$\text{c}$) are measured inclusively and differentially as functions of the transverse momentum and the pseudorapidity of the lepton originating from the W boson decay. The precision of the measurements is improved with respect to previous studies, reaching 1% in $R^\pm_\text{c}$. The precision of the measurements is improved with respect to previous studies, reaching 1% in $R^\pm_\text{c}$ = 0.950 $\pm$ 0.005 (stat) $\pm$ 0.010 (syst). The measurements are compared with theoretical predictions up to next-to-next-to-leading order in perturbative quantum chromodynamics.

13 data tables

Particle level efficiency*acceptance correction factors and cross section measurements for the four channels (W decay to muon or electron and charm identification via muon or secondary vertex inside a jet). The combined measurement is shown in the last row.

Parton level efficiency*acceptance correction factors and cross section measurements for the four channels (W decay to muon or electron and charm identification via muon or secondary vertex inside a jet). The combined measurement is shown in the last row.

Inclusive cross section predictions at QCD NLO accuracy from MCFM using different PDF sets

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Measurements of the associated production of a W boson and a charm quark in proton-proton collisions at $\sqrt{s}$ = 8 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Bergauer, Thomas ; et al.
Eur.Phys.J.C 82 (2022) 1094, 2022.
Inspire Record 1982672 DOI 10.17182/hepdata.114364

Measurements of the associated production of a W boson and a charm (c) quark in proton-proton collisions at a centre-of-mass energy of 8 TeV are reported. The analysis uses a data sample corresponding to a total integrated luminosity of 19.7 fb$^{-1}$ collected by the CMS detector at the LHC. The W bosons are identified through their leptonic decays to an electron or a muon, and a neutrino. Charm quark jets are selected using distinctive signatures of charm hadron decays. The product of the cross section and branching fraction $\sigma$(pp $\to$ W + c + X) $\mathcal{B}$(W $\to$$\ell\nu$), where $\ell$ = e or $\mu$, and the cross section ratio $\sigma$(pp $\to$ W$^+$ + c + X) / $\sigma$(pp $\to$ W$^-$ + $\mathrm{\bar{c}}$ + X) are measured inclusively and differentially as functions of the pseudorapidity and of the transverse momentum of the lepton from the W boson decay. The results are compared with theoretical predictions. The impact of these measurements on the determination of the strange quark distribution is assessed.

6 data tables

Signal yields after background subtraction, efficiency*acceptance correction factors, and cross section measurements for the four channels (W decay to muon or electron and charm identification via muon or secondary vertex inside a jet).

Measured production cross sections $\sigma(W^+ + \overline{c})$, $\sigma(W^- + c)$ and their ratio.

Measured diferential cross sections $\sigma(W^- + c) + \sigma(W^+ + \overline{c})$ as a function of the absolute value of the pseudorapidity of the lepton from the W decay.

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Measurement of $D^{*\pm}$, $D^\pm$ and $D_s^\pm$ meson production cross sections in $pp$ collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Nucl.Phys.B 907 (2016) 717-763, 2016.
Inspire Record 1408878 DOI 10.17182/hepdata.77020

The production of $D^{*\pm}$, $D^\pm$ and $D_s^\pm$ charmed mesons has been measured with the ATLAS detector in $pp$ collisions at $\sqrt{s}=7$ TeV at the LHC, using data corresponding to an integrated luminosity of $280\,$nb$^{-1}$. The charmed mesons have been reconstructed in the range of transverse momentum $3.5<p_{\rm T}(D)<100$ GeV and pseudorapidity $|\eta(D)|<2.1$. The differential cross sections as a function of transverse momentum and pseudorapidity were measured for $D^{*\pm}$ and $D^\pm$ production. The next-to-leading-order QCD predictions are consistent with the data in the visible kinematic region within the large theoretical uncertainties. Using the visible $D$ cross sections and an extrapolation to the full kinematic phase space, the strangeness-suppression factor in charm fragmentation, the fraction of charged non-strange $D$ mesons produced in a vector state, and the total cross section of charm production at $\sqrt{s}=7$ TeV were derived.

4 data tables

The visible low-$p_T$, $3.5<p_T(D)<20\rm{\ GeV}$, and high-$p_T$, $20<p_T(D)<100\rm{\ GeV}$, cross sections of $D^{*\pm}$, $D^\pm$ and $D^\pm_s$ production with $|\eta|<2.1$. The data uncertainties are the total uncertainties obtained as sums in quadrature of the statistical, systematic, luminosity and branching-fraction uncertainties.

The measured differential cross sections $\rm{d}\sigma/\rm{d}p_T$ of $D^{*\pm}$ and $D^\pm$ production with $|\eta|<2.1$. The first and second errors are the statistical and systematic uncertainties, respectively. The systematic uncertainties corresponding to the tracking ($\delta_2$) uncertainties (Table 2 of the paper) are strongly correlated. The fully correlated uncertainties linked with the luminosity measurement ($3.5\%$) and branching fractions ($1.5\%$ and $2.1\%$ for $D^{*\pm}$ and $D^\pm$, respectively) are not shown.

The measured differential cross sections $\rm{d}\sigma/\rm{d}|\eta|$ of $D^{*\pm}$ and $D^\pm$ production with $3.5<p_T<20\,$GeV. The first and second errors are the statistical and systematic uncertainties, respectively. The systematic uncertainty fractions corresponding to the tracking ($\delta_2$) uncertainties (Table 2 of the paper) are strongly correlated. The fully correlated uncertainties linked with the luminosity measurement ($3.5\%$) and branching fractions ($1.5\%$ and $2.1\%$ for $D^{*\pm}$ and $D^\pm$, respectively) are not shown.

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Measurement of the production of a W boson in association with a charm quark in pp collisions at sqrt(s)=7 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
JHEP 05 (2014) 068, 2014.
Inspire Record 1282447 DOI 10.17182/hepdata.63197

The production of a W boson in association with a single charm quark is studied using 4.6 fb^-1 of pp collision data at sqrt(s)=7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96 +0.26 -0.30 at Q^2=1.9 GeV^2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio sigma(W^+ + bar{c})/sigma(W^- + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s-bar{s} quark asymmetry.

17 data tables

Measured integrated cross sections of the production of a W boson with a single c-jet, a D meson or a D* meson times the branching ratio W -> l nu in the fiducial regions together with the statistical and systematic uncertainties. For the W+c-jet cross sections events with more than one c-jet are discarded. The particle-level c-jet is defined as the one containing a weakly decaying c-hadron with pt>5 GeV, within DeltaR<0.3. Jets containing c-hadrons originating from b-hadron decays are not counted as c-jets. Jets are not required for the W+D/D* cross sections. The cross sections are defined for OS-SS events.

Measured integrated cross section ratios of the production of W+ and W- bosons associated with a single c-jet, a D meson or a D* meson in the fiducial regions together with the statistical and systematic uncertainties. For the W+c-jet cross sections events with more than one c-jet are discarded. The particle-level c-jet is defined as the one containing a weakly decaying c-hadron with pt>5 GeV, within DeltaR<0.3. Jets containing c-hadrons originating from b-hadron decays are not counted as c-jets. Jets are not required for the W+D/D* cross sections. The cross sections are defined for OS-SS events.

Measured differential cross sections as function of the lepton pseudo-rapidity of the production of a W boson with a single c-jet times the branching ratio W -> l nu in the fiducial regions together with the statistical and systematic uncertainties. For the W+c-jet cross sections events with more than one c-jet are discarded. The particle-level c-jet is defined as the one containing a weakly decaying c-hadron with pt>5 GeV, within DeltaR<0.3. Jets containing c-hadrons originating from b-hadron decays are not counted as c-jets. The cross sections are defined for OS-SS events.

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Measurement of the inclusive isolated prompt photon cross section in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector using 4.6 fb-1

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Rev.D 89 (2014) 052004, 2014.
Inspire Record 1263495 DOI 10.17182/hepdata.66783

A measurement of the cross section for the production of isolated prompt photons in pp collisions at a center-of-mass energy sqrt(s) = 7 TeV is presented. The results are based on an integrated luminosity of 4.6 fb-1 collected with the ATLAS detector at the LHC. The cross section is measured as a function of photon pseudorapidity and transverse energy in the kinematic range between 100 GeV and 1000 GeV and in the regions of pseudorapidity less than 1.37 and between 1.52 and 2.37. The results are compared to leading-order parton-shower Monte Carlo models and next-to-leading-order perturbative QCD calculations. Next-to-leading-order perturbative QCD calculations agree well with the measured cross sections as a function of transverse energy and pseudorapidity.

3 data tables

Measured inclusive prompt photon production cross section in the pseudorapidity range |eta^gamma| < 1.37 as a function of E_T^gamma with statistical and systematic uncertainties.

Measured inclusive prompt photon production cross section in the pseudorapidity range |eta^gamma| 1.52-2.37 as a function of E_T^gamma with statistical and systematic uncertainties.

Measured inclusive prompt photon production cross section in the ET_gamma region > 100 GeV as a function of |eta(gamma)| with statistical and systematic uncertainties.


Measurement of isolated photons accompanied by jets in deep inelastic ep scattering

The ZEUS collaboration Abramowicz, H. ; Abt, I. ; Adamczyk, L. ; et al.
Phys.Lett.B 715 (2012) 88-97, 2012.
Inspire Record 1117891 DOI 10.17182/hepdata.60574

The production of isolated high-energy photons accompanied by jets has been measured in deep inelastic ep scattering with the ZEUS detector at HERA, using an integrated luminosity of 326 pb^{-1}. Measurements were made for exchanged photon virtualities, Q^2, in the range 10 to 350 GeV^2. The photons were measured in the transverse-energy and pseudorapidity ranges 4 < ET^gamma < 15 GeV and -0.7 < eta^gamma < 0.9, and the jets were measured in the transverse-energy and pseudorapidity ranges 2.5 < ET^jet <35 GeV and -1.5 < eta^jet < 1.8. Differential cross sections are presented as functions of these quantities. Perturbative QCD predictions give a reasonable description of the shape of the measured cross sections over most of the kinematic range, but the absolute normalisation is typically in disagreement by 20-30%.

6 data tables

The measured differential cross section as a function of Q**2.

The measured differential cross section as a function of X.

The measured differential cross section as a function of the transverse energy of the photon.

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Inclusive-jet photoproduction at HERA and determination of alphas

The ZEUS collaboration Abramowicz, H. ; Abt, I. ; Adamczyk, L. ; et al.
Nucl.Phys.B 864 (2012) 1-37, 2012.
Inspire Record 1116258 DOI 10.17182/hepdata.62400

Inclusive-jet cross sections have been measured in the reaction ep->e+jet+X for photon virtuality Q2 < 1 GeV2 and gamma-p centre-of-mass energies in the region 142 < W(gamma-p) < 293 GeV with the ZEUS detector at HERA using an integrated luminosity of 300 pb-1. Jets were identified using the kT, anti-kT or SIScone jet algorithms in the laboratory frame. Single-differential cross sections are presented as functions of the jet transverse energy, ETjet, and pseudorapidity, etajet, for jets with ETjet > 17 GeV and -1 < etajet < 2.5. In addition, measurements of double-differential inclusive-jet cross sections are presented as functions of ETjet in different regions of etajet. Next-to-leading-order QCD calculations give a good description of the measurements, except for jets with low ETjet and high etajet. The influence of non-perturbative effects not related to hadronisation was studied. Measurements of the ratios of cross sections using different jet algorithms are also presented; the measured ratios are well described by calculations including up to O(alphas2) terms. Values of alphas(Mz) were extracted from the measurements and the energy-scale dependence of the coupling was determined. The value of alphas(Mz) extracted from the measurements based on the kT jet algorithm is alphas(Mz) = 0.1206 +0.0023 -0.0022 (exp.) +0.0042 -0.0035 (th.); the results from the anti-kT and SIScone algorithms are compatible with this value and have a similar precision.

12 data tables

The measured differential cross section based on the kT jet algorithm in the kinematic region Q^2<1 GeV^2 and 142 < W < 293 GeV as a function of the jet ET for jet ETARAP -1 TO 2.5 . The first (sys) error is the uncorrelated systematic error and the second is the jet-energy scale uncertainty.

The measured differential cross section based on the kT jet algorithm in the kinematic region Q^2<1 GeV^2 and 142 < W < 293 GeV as a function of the jet ETARAP for jet ET > 17 GeV. The first (sys) error is the uncorrelated systematic error and the second is the jet-energy scale uncertainty.

The measured differential cross section based on the kT jet algorithm in the kinematic region Q^2<1 GeV^2 and 142 < W < 293 GeV as a function of the jet ETARAP for jet ET > 21 GeV. The first (sys) error is the uncorrelated systematic error and the second is the jet-energy scale uncertainty.

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Measurement of D^{+} and Lambda_{c}^{+} production in deep inelastic scattering at HERA

The ZEUS collaboration Abramowicz, H. ; Abt, I. ; Adamczyk, L. ; et al.
JHEP 11 (2010) 009, 2010.
Inspire Record 860842 DOI 10.17182/hepdata.57020

Charm production in deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 120 pb^{-1}. The hadronic decay channels D^{+} -> K^{0}_{S} pi^{+}, Lambda_{c}^{+} -> p K^{0}_{S} and Lambda_{c}^{+} -> Lambda pi^{+}, and their charge conjugates, were reconstructed. The presence of a neutral strange hadron in the final state reduces the combinatorial background and extends the measured sensitivity into the low transverse momentum region. The kinematic range is 0 < p_{T}(D^{+}, Lambda_{c}^{+}) < 10 GeV, |eta(D^{+}, Lambda_{c}^{+})| < 1.6, 1.5 < Q^{2} < 1000 GeV^{2} and 0.02 < y < 0.7. Inclusive and differential cross sections for the production of D^{+} mesons are compared to next-to-leading-order QCD predictions. The fraction of c quarks hadronising into Lambda_{c}^{+} baryons is extracted.

8 data tables

Total visible cross section for D+ production. The second systematic error is due to the uncertainty in the branching ratios for D+ to (KOS PI+).

Total visible cross section for LAMBDA/C+ production via the decay channel into (P K0S). The second systematic error reflects the uncertainty in the branching ratio to (P K0S).

Total visible cross section for LAMBDA/C+ production via the decay channel into (LAMBDA PI+). The second systematic error reflects the uncertainty in the branching ratio to (LAMBDA PI+).

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Inclusive dijet cross sections in neutral current deep inelastic scattering at HERA

The ZEUS collaboration Abramowicz, H. ; Abt, I. ; Adamczyk, L. ; et al.
Eur.Phys.J.C 70 (2010) 965-982, 2010.
Inspire Record 875006 DOI 10.17182/hepdata.71338

Single- and double-differential inclusive dijet cross sections in neutral current deep inelastic ep scattering have been measured with the ZEUS detector using an integrated luminosity of 374 pb^-1. The measurement was performed at large values of the photon virtuality, Q^2, between 125 and 20000 GeV^2. The jets were reconstructed with the k_T cluster algorithm in the Breit reference frame and selected by requiring their transverse energies in the Breit frame, E_T,B^jet, to be larger than 8 GeV. In addition, the invariant mass of the dijet system, M_jj, was required to be greater than 20 GeV. The cross sections are described by the predictions of next-to-leading-order QCD.

18 data tables

The measured differential cross-sections $d\sigma/dQ^2$ for inclusive dijet production. The statistical, uncorrelated systematic and jet-energy-scale (ES) uncertainties are shown separately. The multiplicative corrections, ${C_{\rm{QED}}}$, which have been applied to the data and the corrections for hadronisation and ${Z^{0}}$ effects to be applied to the parton-level NLO QCD calculations, ${C_{\rm{hadr}}\cdot C_{\rm{Z^{0}}}}$, are shown in the last two columns.

Inclusive dijet cross-sections ${d\sigma/dx_{\rm{Bj}}}$. Other details as in the caption to Table 1.

Inclusive dijet cross-sections ${d\sigma/d\overline{E^{jet}_{T,B}}}$. Other details as in the caption to Table 1.

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Measurement of beauty production in DIS and F_2^bbbar extraction at ZEUS

The ZEUS collaboration Abramowicz, H. ; Abt, I. ; Adamczyk, L. ; et al.
Eur.Phys.J.C 69 (2010) 347-360, 2010.
Inspire Record 855232 DOI 10.17182/hepdata.56879

Beauty production in deep inelastic scattering with events in which a muon and a jet are observed in the final state has been measured with the ZEUS detector at HERA using an integrated luminosity of 114 pb^-1. The fraction of events with beauty quarks in the data was determined using the distribution of the transverse momentum of the muon relative to the jet. The cross section for beauty production was measured in the kinematic range of photon virtuality, Q^2 > 2 Gev^2, and inelasticity, 0.05 < y < 0.7, with the requirement of a muon and a jet. Total and differential cross sections are presented and compared to QCD predictions. The beauty contribution to the structure function F_2 was extracted and is compared to theoretical predictions.

18 data tables

Total visible cross section for BBAR production and decay into MUON+JET.

Measured differential cross section as a function of Q**2.

Measured differential cross section as a function of the muon transverse momentum.

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