Measurement of $Z\gamma\gamma$ production in $pp$ collisions at $\sqrt{s}= 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, D.C. ; et al.
Eur.Phys.J.C 83 (2023) 539, 2023.
Inspire Record 2593322 DOI 10.17182/hepdata.132903

Cross-sections for the production of a $Z$ boson in association with two photons are measured in proton$-$proton collisions at a centre-of-mass energy of 13 TeV. The data used correspond to an integrated luminosity of 139 fb$^{-1}$ recorded by the ATLAS experiment during Run 2 of the LHC. The measurements use the electron and muon decay channels of the $Z$ boson, and a fiducial phase-space region where the photons are not radiated from the leptons. The integrated $Z(\rightarrow\ell\ell)\gamma\gamma$ cross-section is measured with a precision of 12% and differential cross-sections are measured as a function of six kinematic variables of the $Z\gamma\gamma$ system. The data are compared with predictions from MC event generators which are accurate to up to next-to-leading order in QCD. The cross-section measurements are used to set limits on the coupling strengths of dimension-8 operators in the framework of an effective field theory.

16 data tables

Measured fiducial-level integrated cross-section. NLO predictions from Sherpa 2.2.10 and MadGraph5_aMC@NLO 2.7.3 are also shown. The uncertainty in the predictions is divided into statistical and theoretical uncertainties (scale and PDF+$\alpha_{s}$).

Measured unfolded differential cross-section as a function of the leading photon transverse energy $E^{\gamma1}_{\mathrm{T}}$. NLO predictions from Sherpa 2.2.10 and MadGraph5_aMC@NLO 2.7.3 are also shown. The uncertainty in the predictions is divided into statistical and theoretical uncertainties (scale and PDF+$\alpha_{s}$).

Measured unfolded differential cross-section as a function of the subleading photon transverse energy $E^{\gamma2}_{\mathrm{T}}$. NLO predictions from Sherpa 2.2.10 and MadGraph5_aMC@NLO 2.7.3 are also shown. The uncertainty in the predictions is divided into statistical and theoretical uncertainties (scale and PDF+$\alpha_{s}$).

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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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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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Measurement of D+- and D0 production in deep inelastic scattering using a lifetime tag at HERA

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Eur.Phys.J.C 63 (2009) 171-188, 2009.
Inspire Record 810112 DOI 10.17182/hepdata.51856

The production of D+- and D0 mesons has been measured with the ZEUS detector at HERA using an integrated luminosity of 133.6 pb-1. The measurements cover the kinematic range 5 < Q^2 < 1000 GeV^2, 0.02 < y < 0.7, 1.5 < p_T^D < 15 GeV and eta^D < 1.6. Combinatorial background to the D meson signals is reduced by using the ZEUS microvertex detector to reconstruct displaced secondary vertices. Production cross sections are compared with the predictions of next-to-leading-order QCD which is found to describe the data well. Measurements are extrapolated to the full kinematic phase space in order to obtain the open-charm contribution, F2^ccbar, to the proton structure function, F2.

21 data tables

Production cross section for (D+ + D-) mesons.

Production cross section for (D0 + DBAR0) mesons not originating from D*+- decays.

Measured D+- cross section as a function of Q**2.

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Beauty photoproduction using decays into electrons at HERA

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Phys.Rev.D 78 (2008) 072001, 2008.
Inspire Record 786814 DOI 10.17182/hepdata.45317

Photoproduction of beauty quarks in events with two jets and an electron associated with one of the jets has been studied with the ZEUS detector at HERA using an integrated luminosity of 120pb^-1. The fractions of events containing b quarks, and also of events containing c quarks, were extracted from a likelihood fit using variables sensitive to electron identification as well as to semileptonic decays. Total and differential cross sections for beauty and charm production were measured and compared with next-to-leading-order QCD calculations and Monte Carlo models.

7 data tables

Total cross sections for electrons from beauty and charm quarks.

Differential electron cross sections as a function of PT and ETARAP from beauty and charm quarks.

Differential electron cross sections as a function of PT and ETARAP from beauty and charm quarks.

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Diffractive Photoproduction of D*+/-(2010) at HERA

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Eur.Phys.J.C 51 (2007) 301-315, 2007.
Inspire Record 747652 DOI 10.17182/hepdata.45627

Diffractive photoproduction of D*+/-(2010) mesons was measured with the ZEUS detector at the ep collider HERA, using an integrated luminosity of 78.6 pb^{-1}. The D* mesons were reconstructed in the kinematic range: transverse momentum p_T(D*) > 1.9 GeV and pseudorapidity |eta(D*)| < 1.6, using the decay D*+ -> D0 pi+_s followed by D0 -> K- pi+ (+c.c.). Diffractive events were identified by a large gap in pseudorapidity between the produced hadronic state and the outgoing proton. Cross sections are reported for photon-proton centre-of-mass energies in the range 130 < W < 300 GeV and for photon virtualities Q^2 < 1 GeV^2, in two ranges of the Pomeron fractional momentum x_pom < 0.035 and x_pom < 0.01. The relative contribution of diffractive events to the inclusive D*+/-(2010) photoproduction cross section is about 6%. The data are in agreement with perturbative QCD calculations based on various parameterisations of diffractive parton distribution functions. The results are consistent with diffractive QCD factorisation.

12 data tables

Total cross section integrated over the given kinematic range.

Ratio of diffractive to inclusive D* cross section.

Differential cross sections for diffractive photoproduction of D*+- mesons as a function of X(NAME=POMERON).

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Measurement of D*+- meson production in ep scattering at low Q^2

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Phys.Lett.B 649 (2007) 111-121, 2007.
Inspire Record 745058 DOI 10.17182/hepdata.45591

The production of D*+-(2010) mesons in ep scattering in the range of exchanged photon virtuality 0.05 &lt; Q^2 &lt; 0.7 GeV^2 has been measured with the ZEUS detector at HERA using an integrated luminosity of 82 pb-1. The decay channels D*+ -> D0 pi+ with D0 -> K- pi+ and corresponding antiparticle decay were used to identify D* mesons and the ZEUS beampipe calorimeter was used to identify the scattered electron. Differential D* cross sections as functions of Q^2, inelasticity, y, transverse momentum of the D* meson, p_T(D*), and pseudorapidity of the D* meson, eta(D*), have been measured in the kinematic region 0.02 &lt; y &lt; 0.85, 1.5 &lt; p_T(D*) &lt; 9.0 GeV and |eta(D*)| &lt; 1.5. The measured differential cross sections are in agreement with two different NLO QCD calculations. The cross sections are also compared to previous ZEUS measurements in the photoproduction and DIS regimes.

7 data tables

Total cross section measurement.. The second DSYS error is due to the uncertainty in the branching ratio.

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

Measured differential cross section as a function of Y.

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Inclusive jet cross sections and dijet correlations in D*+- photoproduction at HERA.

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Nucl.Phys.B 729 (2005) 492-525, 2005.
Inspire Record 687943 DOI 10.17182/hepdata.46048

Inclusive jet cross sections in photoproduction for events containing a $D^*$ meson have been measured with the ZEUS detector at HERA using an integrated luminosity of $78.6 {\rm pb}^{-1}$. The events were required to have a virtuality of the incoming photon, $Q^2$, of less than 1 GeV$^2$, and a photon-proton centre-of-mass energy in the range $130&lt;W_{\gamma p}&lt;280 {\rm GeV}$. The measurements are compared with next-to-leading-order (NLO) QCD calculations. Good agreement is found with the NLO calculations over most of the measured kinematic region. Requiring a second jet in the event allowed a more detailed comparison with QCD calculations. The measured dijet cross sections are also compared to Monte Carlo (MC) models which incorporate leading-order matrix elements followed by parton showers and hadronisation. The NLO QCD predictions are in general agreement with the data although differences have been isolated to regions where contributions from higher orders are expected to be significant. The MC models give a better description than the NLO predictions of the shape of the measured cross sections.

29 data tables

Cross section as a function of the jet transverse energy for INCLUSIVE events containing at least one D* meson in different jet pseudorapidity regions.

Cross section as a function of the jet transverse energy for INCLUSIVE events containing at least one D* meson in different jet pseudorapidity regions.

Cross section as a function of the jet transverse energy for INCLUSIVE events containing at least one D* meson in different jet pseudorapidity regions.

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Measurement of beauty production in deep inelastic scattering at HERA

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Loizides, J.H. ; et al.
Phys.Lett.B 599 (2004) 173-189, 2004.
Inspire Record 650875 DOI 10.17182/hepdata.53981

The beauty production cross section for deep inelastic scattering events with at least one hard jet in the Breit frame together with a muon has been measured, for photon virtualities Q^2 > 2 GeV^2, with the ZEUS detector at HERA using integrated luminosity of 72 pb^-1. The total visible cross section is sigma_b-bbar (ep -> e jet mu X) = 40.9 +- 5.7 (stat.) +6.0 -4.4 (syst.) pb. The next-to-leading order QCD prediction lies about 2.5 standard deviations below the data. The differential cross sections are in general consistent with the NLO QCD predictions: however at low values of Q^2, Bjorken x, and muon transverse momentum, and high values of jet transverse energy and muon pseudorapidity, the prediction is about two standard deviations below the data.

6 data tables

Total visible cross section in the specified kinematic region.

Differential cross section w.r.t. Q**2.

Differential cross section w.r.t. log10(x).

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Photoproduction of D*+- mesons associated with a leading neutron.

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Krakauer, D. ; et al.
Phys.Lett.B 590 (2004) 143-160, 2004.
Inspire Record 642709 DOI 10.17182/hepdata.46281

The photoproduction of $D^{*\pm} (2010)$ mesons associated with a leading neutron has been observed with the ZEUS detector in $ep$ collisions at HERA using an integrated luminosity of 80 pb$^{-1}$. The neutron carries a large fraction, {$x_L>0.2$}, of the incoming proton beam energy and is detected at very small production angles, {$\theta_n<0.8$ mrad}, an indication of peripheral scattering. The $D^*$ meson is centrally produced with pseudorapidity {$|\eta|<1.5$}, and has a transverse momentum {$p_{\it T} > 1.9$ GeV}, which is large compared to the average transverse momentum of the neutron of 0.22 GeV. The ratio of neutron-tagged to inclusive $D^*$ production is $8.85\pm 0.93({\rm stat.})^{+0.48}_{-0.61}({\rm syst.})\%$ in the photon-proton center-of-mass energy range {$130 <W<280$ GeV}. The data suggest that the presence of a hard scale enhances the fraction of events with a leading neutron in the final state.

8 data tables

Integrated cross section. The first DSYS error includes the uncertainty in the luminosity and the second DSYS error is due to the knowledge of the branching ratios.

No description provided.

No description provided.

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