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Combination of Differential D^{*\pm} Cross-Section Measurements in Deep-Inelastic ep Scattering at HERA

The H1 & ZEUS collaborations Abramowicz, H. ; Abt, I. ; Adamczyk, L. ; et al.
JHEP 09 (2015) 149, 2015.
Inspire Record 1353667 DOI 10.17182/hepdata.73328

H1 and ZEUS have published single-differential cross sections for inclusive D^{*\pm}-meson production in deep-inelastic ep scattering at HERA from their respective final data sets. These cross sections are combined in the common visible phase-space region of photon virtuality Q2 > 5 GeV2, electron inelasticity 0.02 < y < 0.7 and the D^{*\pm} meson's transverse momentum pT (D^*) > 1.5 GeV and pseudorapidity |eta(D^*)| < 1.5. The combination procedure takes into account all correlations, yielding significantly reduced experimental uncertainties. Double-differential cross sections d2s /dQ2dy are combined with earlier D^{*\pm} data, extending the kinematic range down to Q2 > 1.5 GeV2. Perturbative next-to-leadingorder QCD predictions are compared to the results.

6 data tables

The combined differential $D^{*\pm}$-production cross section as a function of $p_T(D^{*})$, with its uncorrelated and correlated uncertainties.

The combined differential $D^{*\pm}$-production cross section as a function of $\eta(D^{*})$, with its uncorrelated and correlated uncertainties.

The combined differential $D^{*\pm}$-production cross section as a function of $z(D^{*})$, with its uncorrelated and correlated uncertainties.

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Measurement of high-Q2 neutral current deep inelastic e+p scattering cross sections with a longitudinally polarised positron beam at HERA

The ZEUS collaboration Abramowicz, H. ; Abt, I. ; Adamczyk, L. ; et al.
Phys.Rev.D 87 (2013) 052014, 2013.
Inspire Record 1183813 DOI 10.17182/hepdata.62614

Measurements of neutral current cross sections for deep inelastic scattering in e+p collisions at HERA with a longitudinally polarised positron beam are presented. The single-differential cross-sections d(sigma)/dQ2, d(sigma)/dx and d(sigma)/dy and the reduced cross-section were measured in the kinematic region Q2 > 185 GeV2 and y < 0.9, where Q2 is the four-momentum transfer squared, x the Bjorken scaling variable, and y the inelasticity of the interaction. The measurements were performed separately for positively and negatively polarised positron beams. The measurements are based on an integrated luminosity of 135.5 pb-1 collected with the ZEUS detector in 2006 and 2007 at a centre-of-mass energy of 318 GeV. The structure functions F3 and F3(gamma)Z were determined by combining the e+p results presented in this paper with previously published e-p neutral current results. The asymmetry parameter A+ is used to demonstrate the parity violation predicted in electroweak interactions. The measurements are well described by the predictions of the Standard Model.

26 data tables

The single-differential cross section DSIG/DQ**2 (Y<0.9,Y(1-x)**2>0.004), corrected to the electroweak Born level, for zero polarisation, Pe=0.

The single-differential cross section DSIG/DQ**2 (Y<0.9,Y(1-x)**2>0.004), corrected to the electroweak Born level, for positive (Pe=+0.32) and negative (Pe=-0.36) polarisations.

The single-differential cross section DSIG/DX (Y<0.9,Y(1-x)**2>0.004) at Q^2=185 GeV^2, corrected to the electroweak Born level, for zero (Pe=0), positive (Pe=+0.32) and negative (Pe=-0.36) polarisations.

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Measurement of charged current deep inelastic scattering cross sections with a longitudinally polarised electron beam at HERA

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Eur.Phys.J.C 61 (2009) 223-235, 2009.
Inspire Record 810120 DOI 10.17182/hepdata.51622

Measurements of the cross sections for charged current deep inelastic scattering in e-p collisions with longitudinally polarised electron beams are presented. The measurements are based on a data sample with an integrated luminosity of 175 pb-1 collected with the ZEUS detector at HERA at a centre-of-mass energy of 318 GeV. The total cross section is given for positively and negatively polarised electron beams. The differential cross-sections dsigma/dQ2, dsigma/dx and dsigma/dy are presented for Q2>200 GeV2. The double-differential cross-section d2sigma/dxdQ2 is presented in the kinematic range 280&lt;Q2&lt;30000 GeV2 and 0.015&lt;x&lt;0.65. The measured cross sections are compared with the predictions of the Standard Model.

38 data tables

Total cross section for CC DIS events for two values of the longitudinal polarization of the electron beam.

Total cross section for CC DIS events as a function of the longitudinal polarization of the electron beam.

Differential cross section DSIG/DQ**2 for the two values of longitudinal polarization of the electron beam.

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Diffractive photoproduction of dijetsin $ep$ collisions at HERA

The ZEUS collaboration Chekanov, Sergei ; Derrick, M. ; Magill, S. ; et al.
Eur.Phys.J.C 55 (2008) 177-191, 2008.
Inspire Record 763404 DOI 10.17182/hepdata.63789

Diffractive photoproduction of dijets was measured with the ZEUS detector at the ep collider HERA using an integrated luminosity of 77.2 pb-1. The measurements were made in the kinematic range Q^2 < 1 GeV^2, 0.20 < y < 0.85 and x_pom < 0.025, where Q^2 is the photon virtuality, y is the inelasticity and x_pom is the fraction of the proton momentum taken by the diffractive exchange. The two jets with the highest transverse energy, E_T^jet, were required to satisfy E_T^jet > 7.5 and 6.5 GeV, respectively, and to lie in the pseudorapidity range -1.5 < eta^jet < 1.5. Differential cross sections were compared to perturbative QCD calculations using available parameterisations of diffractive parton distributions of the proton.

15 data tables

Differential cross section DSIG/DY for diffractive photoproduction of dijets as a function of Y.

Differential cross section DSIG/DM(P=5_6_7) for diffractive photoproduction of dijets as a function of M(P=5_6_7).

Differential cross section DSIG/DX(NAME=POMERON) for diffractive photoproduction of dijets as a function of X(NAME=POMERON).

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Three- and four-jet final states in photoproduction at HERA

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Nucl.Phys.B 792 (2008) 1-47, 2008.
Inspire Record 756660 DOI 10.17182/hepdata.45526

Three- and four-jet final states have been measured in photoproduction at HERA using the ZEUS detector with an integrated luminosity of 121 pb^-1. The results are presented for jets with transverse energy E_T^jet>6 GeV and pseudorapidity |eta^jet|<2.4, in the kinematic region given by the virtuality of the photon Q^2<1 GeV^2 and the inelasticity 0.2<y<0.85 and in two mass regions defined as 25<M_nj<50 GeV and M_nj>50 GeV, where M_nj is the invariant mass of the n-jet system. The four-jet photoproduction cross section has been measured for the first time and represents the highest-order process studied at HERA. Both the three- and four-jet cross sections have been compared with leading-logarithmic parton-shower Monte Carlo models, with and without multi-parton interactions. The three-jet cross sections have been compared to an order(alpha alpha_s^2) perturbative QCD calculation.

21 data tables

Cross section D(SIG)/M(P=4_5_6) as a function of M(P=4_5_6) .

Cross section D(SIG)/M(P=4_5_6_7) as a function of M(P=4_5_6_7) .

Cross section D(SIG)/X(C=GAMMA,OBS) as a function of X(C=GAMMA,OBS) in two jet invariant mass regions, 25 to 50 and > 50 GeV .

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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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Measurement of high-Q**2 deep inelastic scattering cross sections with a longitudinally polarised positron beam at HERA.

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Phys.Lett.B 637 (2006) 210-222, 2006.
Inspire Record 710347 DOI 10.17182/hepdata.45995

The cross sections for charged and neutral current deep inelastic scattering in e^+p collisions with a longitudinally polarised positron beam have been measured using the ZEUS detector at HERA. The results, based on data corresponding to an integrated luminosity of 23.8 pb^-1 at sqrt(s) = 318 GeV, are given for both e^+p charged current and neutral current deep inelastic scattering for both positive and negative values of the longitudinal polarisation of the positron beam. Single differential cross sections are presented for the kinematic region Q^2 > 200 GeV^2 . The measured cross sections are compared to the predictions of the Standard Model. A fit to the data yields sigma^CC (P_e = -1) = 7.4 +/- 3.9 (stat.) +/- 1.2 (syst.) pb, which is consistent within two standard deviations with the absence of right-handed charged currents in the Standard Model.

5 data tables

Total cross sections for the E+ P CC DIS at Q**2 > 200 GeV for the two different longitudinal positron polarizations and extrapolated with a linear fit to a polarization of -1.0 (including earlier unpolarized data).

E+ P CC DIS cross section as a function of Q**2.

E+ P CC DIS cross section as a function of X.

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High-Q**2 neutral current cross sections in e+ p deep inelastic scattering at s**(1/2) = 318-GeV.

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Krakauer, D. ; et al.
Phys.Rev.D 70 (2004) 052001, 2004.
Inspire Record 636641 DOI 10.17182/hepdata.46282

Cross sections for e^+p neutral current deep inelastic scattering have been measured at a centre-of-mass energy of sqrt{s}=318 GeV with the ZEUS detector at HERA using an integrated luminosity of 63.2 pb^-1. The double-differential cross section, d^2sigma/dxdQ^2, is presented for 200 GeV^2 < Q^2 < 30000 GeV^2 and for 0.005 < x < 0.65. The single-differential cross-sections dsigma/dQ^2, dsigma/dx and dsigma/dy are presented for Q^2 > 200 GeV^2. The effect of Z-boson exchange is seen in dsigma/dx measured for Q^2 > 10000 GeV^2. The data presented here were combined with ZEUS e^+p neutral current data taken at sqrt{s}=300 GeV and the structure function F_2^{em} was extracted. All results agree well with the predictions of the Standard Model.

38 data tables

The single differential DSIG/DQ**2 cross section corrected to the electroweak Born level. See next table for a breakdown of the systematic errors.

Systematic errors with bin to bin correlations for the cross section DSIG/DQ**2.

Single differential cross section DSIG/DX for a Q**2 cut of 200 GeV**2 corrected to the electroweak Born level.

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Measurement of high-Q**2 charged current cross sections in e+ p deep inelastic scattering at HERA.

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Krakauer, D. ; et al.
Eur.Phys.J.C 32 (2003) 1-16, 2003.
Inspire Record 623557 DOI 10.17182/hepdata.46433

Cross sections for e^+p charged current deep inelastic scattering at a centre-of-mass energy of 318 GeV have been determined with an integrated luminosity of 60.9pb^-1 collected with the ZEUS detector at HERA. The differential cross sections dsigma/dQ^2, dsigma/dx and dsigma/dy for Q^2>200 GeV^2 are presented. In addition, d^2sigma/dxdQ^2 has been measured in the kinematic range 280 GeV^2 < Q^2 < 17000 GeV^2 and 0.008 < x < 0.42. The predictions of the Standard Model agree well with the measured cross sections. The mass of the W boson propagator is determined to be M_W=78.9 +/- 2.0 (stat.) +/- 1.8 (syst.) +2.0 -1.8 (PDF) GeV from a fit to dsigma/dQ^2. The chiral structure of the Standard Model is also investigated in terms of the (1-y)^2 dependence of the the double-differential cross section. The structure-function F_2^CC has been extracted by combining the measurements presented here with previous ZEUS results from e^-p scattering, extending the measurement obtained in a neutrino-nucleus scattering experiment to a significantly higher Q^2 region.

12 data tables

The total cross section for Q**2 > 200 GeV**2.

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

The differential cross section as a function of X.

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Measurement of high-Q**2 e- p neutral current cross sections at HERA and the extraction of xF3.

The ZEUS collaboration Chekanov, S. ; Krakauer, D. ; Magill, S. ; et al.
Eur.Phys.J.C 28 (2003) 175-201, 2003.
Inspire Record 593481 DOI 10.17182/hepdata.46560

Cross sections for e^-p neutral current deep inelastic scattering have been measured at a centre-of-mass energy of 318 GeV using an integrated luminosity of 15.9 pb^-1 collected with the ZEUS detector at HERA. Results on the double-differential cross-section d^2s/dxdQ^2 in the range 185 < Q^2 < 50000 GeV^2 and 0.0037 < x < 0.75, as well as the single-differential cross-sections ds/dQ^2, ds/dx and ds/dy for Q^2 > 200 GeV^2, are presented. To study the effect of Z-boson exchange, ds/dx has also been measured for Q^2 > 10000 GeV^2. The structure function xF_3 has been extracted by combining the e^-p results presented here with the recent ZEUS measurements of e^+p neutral current deep inelastic scattering. All results agree well with the predictions of the Standard Model.

32 data tables

Differential cross section DSIG/DQ**2.

Differential cross section DSIG/DX for two Q**2 regions.

Differential cross section DSIG/DY.

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