Version 2
Production of D*+- mesons with dijets in deep-inelastic scattering at HERA.

The H1 collaboration Aktas, A. ; Andreev, V. ; Anthonis, T. ; et al.
Eur.Phys.J.C 51 (2007) 271-287, 2007.
Inspire Record 736052 DOI 10.17182/hepdata.45686

Inclusive D* production is measured in deep-inelastic ep scattering at HERA with the H1 detector. In addition, the production of dijets in events with a D* meson is investigated. The analysis covers values of photon virtuality 2< Q^2 <=100 GeV^2 and of inelasticity 0.05<= y <= 0.7. Differential cross sections are measured as a function of Q^2 and x and of various D* meson and jet observables. Within the experimental and theoretical uncertainties all measured cross sections are found to be adequately described by next-to-leading order (NLO) QCD calculations, based on the photon-gluon fusion process and DGLAP evolution, without the need for an additional resolved component of the photon beyond what is included at NLO. A reasonable description of the data is also achieved by a prediction based on the CCFM evolution of partons involving the k_T-unintegrated gluon distribution of the proton.

62 data tables

Visible cross section for inclusive D*+- production.

Visible cross section for inclusive D*+- production.

Visible cross section for inclusive D*+- production with two jets.

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Version 2
Forward jet and particle production at HERA

The H1 collaboration Adloff, C. ; Anderson, M. ; Andreev, V. ; et al.
Nucl.Phys.B 538 (1999) 3-22, 1999.
Inspire Record 476801 DOI 10.17182/hepdata.44172

Single particles and jets in deeply inelastic scattering at low x are measured with the H1 detector in the region away from the current jet and towards the proton remnant, known as the forward region. Hadronic final state measurements in this region are expected to be particularly sensitive to QCD evolution effects. Jet cross-sections are presented as a function of Bjorken-x for forward jets produced with a polar angle to the proton direction, theta, in the range 7 < theta < 20 degrees. Azimuthal correlations are studied between the forward jet and the scattered lepton. Charged and neutral single particle production in the forward region are measured as a function of Bjorken-x, in the range 5 < theta < 25 degrees, for particle transverse momenta larger than 1 GeV. QCD based Monte Carlo predictions and analytical calculations based on BFKL, CCFM and DGLAP evolution are compared to the data. Predictions based on the DGLAP approach fail to describe the data, except for those which allow for a resolved photon contribution.

11 data tables

Forward Jet cross section. Axis error includes +- 7/7 contribution (Dependence of the model used to correct the data).

Forward Di-jet cross section. Axis error includes +- 7/7 contribution (Dependence of the model used to correct the data).

Data from Figure 3a on charged particle production

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Measurement of beauty production at HERA using events with muons and jets

The H1 collaboration Aktas, A. ; Andreev, V. ; Anthonis, T. ; et al.
Eur.Phys.J.C 41 (2005) 453-467, 2005.
Inspire Record 676166 DOI 10.17182/hepdata.110966

A measurement of the beauty production cross section in ep collisions at a centre-of-mass energy of 319 GeV is presented. The data were collected with the H1 detector at the HERA collider in the years 1999-2000. Events are selected by requiring the presence of jets and muons in the final state. Both the long lifetime and the large mass of b-flavoured hadrons are exploited to identify events containing beauty quarks. Differential cross sections are measured in photoproduction, with photon virtualities Q^2 < 1 GeV^2, and in deep inelastic scattering, where 2 < Q^2 < 100 GeV^2. The results are compared with perturbative QCD calculations to leading and next-to-leading order. The predictions are found to be somewhat lower than the data.

10 data tables

Muons and jets from beauty photoproduction, pseudorapidity.

Muons and jets from beauty photoproduction, muon transverse momentum.

Muons and jets from beauty photoproduction, leading jet transverse momentum

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Measurement of Jet Production Cross Sections in Deep-inelastic $ep$ Scattering at HERA

The H1 collaboration Collaboration, H1 ; Andreev, Vladimir ; Baghdasaryan, Artem ; et al.
Eur.Phys.J.C 77 (2017) 215, 2017.
Inspire Record 1496981 DOI 10.17182/hepdata.86390

A precision measurement of jet cross sections in neutral current deep-inelastic scattering for photon virtualities $5.5<Q^2<80\,{\rm GeV}^2$ and inelasticities $0.2<y<0.6$ is presented, using data taken with the H1 detector at HERA, corresponding to an integrated luminosity of $290\,{\rm pb}^{-1}$. Double-differential inclusive jet, dijet and trijet cross sections are measured simultaneously and are presented as a function of jet transverse momentum observables and as a function of $Q^2$. Jet cross sections normalised to the inclusive neutral current DIS cross section in the respective $Q^2$-interval are also determined. Previous results of inclusive jet cross sections in the range $150<Q^2<15\,000\,{\rm GeV}^2$ are extended to low transverse jet momenta $5<P_{T}^{\rm jet}<7\,{\rm GeV}$. The data are compared to predictions from perturbative QCD in next-to-leading order in the strong coupling, in approximate next-to-next-to-leading order and in full next-to-next-to-leading order. Using also the recently published H1 jet data at high values of $Q^2$, the strong coupling constant $\alpha_s(M_Z)$ is determined in next-to-leading order.

55 data tables

Inclusive jet cross sections measured as a function of $P_T^{\rm jet}$ for $Q^2$ = 5.5-8.0 GeV$^2$. The correction factors on the theoretical cross sections $c^{\rm had}$ are listed together with their uncertainties. The radiative correction factors $c^{\rm rad}$ are already included in the quoted cross sections. Note that the uncertainties labelled $\delta^{E_{e^\prime}}$ and $\delta^{\theta_{e^\prime}}$ in Table 6 of the paper (arXiv:1611.03421v3) should be swapped. See Table 5 of arXiv:1406.4709v2 for details of the correlation model.

Inclusive jet cross sections measured as a function of $P_T^{\rm jet}$ for $Q^2$ = 8.0-11.0 GeV$^2$. The correction factors on the theoretical cross sections $c^{\rm had}$ are listed together with their uncertainties. The radiative correction factors $c^{\rm rad}$ are already included in the quoted cross sections. Note that the uncertainties labelled $\delta^{E_{e^\prime}}$ and $\delta^{\theta_{e^\prime}}$ in Table 6 of the paper (arXiv:1611.03421v3) should be swapped. See Table 5 of arXiv:1406.4709v2 for details of the correlation model.

Inclusive jet cross sections measured as a function of $P_T^{\rm jet}$ for $Q^2$ = 11.0-16.0 GeV$^2$. The correction factors on the theoretical cross sections $c^{\rm had}$ are listed together with their uncertainties. The radiative correction factors $c^{\rm rad}$ are already included in the quoted cross sections. Note that the uncertainties labelled $\delta^{E_{e^\prime}}$ and $\delta^{\theta_{e^\prime}}$ in Table 6 of the paper (arXiv:1611.03421v3) should be swapped. See Table 5 of arXiv:1406.4709v2 for details of the correlation model.

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Jet Production in ep Collisions at Low Q^2 and Determination of alpha_s

The H1 collaboration Aaron, F.D. ; Aldaya Martin, M. ; Alexa, C. ; et al.
Eur.Phys.J.C 67 (2010) 1-24, 2010.
Inspire Record 838435 DOI 10.17182/hepdata.31170

The production of jets is studied in deep-inelastic e+p scattering at low negative four momentum transfer squared 5<Q^2<100 GeV^2 and at inelasticity 0.2<y<0.7 using data recorded by the H1 detector at HERA in the years 1999 and 2000, corresponding to an integrated luminosity of 43.5 pb^-1. Inclusive jet, 2-jet and 3-jet cross sections as well as the ratio of 3-jet to 2-jet cross sections are measured as a function of Q^2 and jet transverse momentum. The 2-jet cross section is also measured as a function of the proton momentum fraction xi. The measurements are well described by perturbative quantum chromodynamics at next-to-leading order corrected for hadronisation effects and are subsequently used to extract the strong coupling alpha_s.

13 data tables

Inclusive Jet Cross Section ${\rm\frac{d\sigma_{jet}}{dQ^2}}$.

2-Jet Cross Section ${\rm\frac{d\sigma_{2-jet}}{dQ^2}}$.

3-Jet Cross Section ${\rm\frac{d\sigma_{3-jet}}{dQ^2}}$.

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Jet Production in ep Collisions at High Q^2 and Determination of alpha_s

The H1 collaboration Aaron, F.D. ; Alexa, C. ; Alimujiang, K. ; et al.
Eur.Phys.J.C 65 (2010) 363-383, 2010.
Inspire Record 818707 DOI 10.17182/hepdata.70833

The production of jets is studied in deep-inelastic ep scattering at large negative four momentum transfer squared 150&lt;Q^2&lt;15000 GeV^2 using HERA data taken in 1999-2007, corresponding to an integrated luminosity of 395 pb^-1. Inclusive jet, 2-jet and 3-jet cross sections, normalised to the neutral current deep-inelastic scattering cross sections, are measured as functions of Q^2, jet transverse momentum and proton momentum fraction. The measurements are well described by perturbative QCD calculations at next-to-leading order corrected for hadronisation effects. The strong coupling as determined from these measurements is alpha_s(M_Z) = 0.1168 +/-0.0007 (exp.) +0.0046/-0.0030 (th.) +/-0.0016(pdf).

7 data tables

Normalised inclusive jet cross section in bins of $Q^{2}$.

Normalised 2-jet cross section in bins of $Q^{2}$.

Normalised 3-jet cross section in bins of $Q^{2}$.

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Measurement of Multijet Production in ep Collisions at High Q^2 and Determination of the Strong Coupling alpha_s

The H1 collaboration Andreev, V. ; Baghdasaryan, A. ; Begzsuren, K. ; et al.
Eur.Phys.J.C 75 (2015) 65, 2015.
Inspire Record 1301218 DOI 10.17182/hepdata.64353

Inclusive jet, dijet and trijet differential cross sections are measured in neutral current deep-inelastic scattering for exchanged boson virtualities 150 < Q^2 < 15000 GeV^2 using the H1 detector at HERA. The data were taken in the years 2003 to 2007 and correspond to an integrated luminosity of 351 pb^{-1}. Double differential Jet cross sections are obtained using a regularised unfolding procedure. They are presented as a function of Q^2 and the transverse momentum of the jet, P_T^jet, and as a function of Q^2 and the proton's longitudinal momentum fraction, Xi, carried by the parton participating in the hard interaction. In addition normalised double differential jet cross sections are measured as the ratio of the jet cross sections to the inclusive neutral current cross sections in the respective Q^2 bins of the jet measurements. Compared to earlier work, the measurements benefit from an improved reconstruction and calibration of the hadronic final state. The cross sections are compared to perturbative QCD calculations in next-to-leading order and are used to determine the running coupling and the value of the strong coupling constant as alpha_s(M_Z) = 0.1165 (8)_exp (38)_{pdf,theo}.

20 data tables

Double-differential inclusive jet cross sections measured as a function of Q**2 and PT(JET) using the kT jet algorithm. The total systematic uncertainty sums all systematic uncertainties in quadrature, including the uncertainty due to the LAr noise of 0.5% and the total normalisation uncertainty of 2.9%. The correction factors on the theoretical cross sections C(HAD) and C(EW) are listed in the rightmost columns.

Double-differential dijet cross sections measured as a function of Q**2 and MEAN(PT(2JET)) using the kT jet algorithm. The total systematic uncertainty sums all systematic uncertainties in quadrature, including the uncertainty due to the LAr noise of 0.6% and the total normalisation uncertainty of 2.9%. The correction factors on the theoretical cross sections C(HAD) and C(EW) are listed in the rightmost columns.

Double-differential dijet cross sections measured as a function of Q**2 and XI(2) using the kT jet algorithm. The total systematic uncertainty sums all systematic uncertainties in quadrature, including the uncertainty due to the LAr noise of 0.6% and the total normalisation uncertainty of 2.9%. The correction factors on the theoretical cross sections C(HAD) and C(EW) are listed in the rightmost columns.

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Diffractive Dijet Photoproduction in ep Collisions at HERA

The H1 collaboration Aaron, F.D. ; Alexa, C. ; Andreev, V. ; et al.
Eur.Phys.J.C 70 (2010) 15-37, 2010.
Inspire Record 857109 DOI 10.17182/hepdata.61487

Measurements are presented of single and double-differential dijet cross sections in diffractive photoproduction based on a data sample with an integrated luminosity of 47 pb^-1. The events are of the type ep -> eXY, where the hadronic system X contains at least two jets and is separated by a large rapidity gap from the system Y, which consists of a leading proton or low-mass proton excitation. The dijet cross sections are compared with QCD calculations at next-to-leading order and with a Monte Carlo model based on leading order matrix elements with parton showers. The measured cross sections are smaller than those obtained from the next-to-leading order calculations by a factor of about 0.6. This suppression factor has no significant dependence on the fraction x_gamma of the photon four-momentum entering the hard subprocess. Ratios of the diffractive to the inclusive dijet cross sections are measured for the first time and are compared with Monte Carlo models.

18 data tables

Total diffractive dijet positron-proton cross section integrated over the full measured kinematic range.

Bin averaged hadron level differential cross section for diffractive dijet production as a function of X(C=GAMMA). The first systematic error is the uncorrelated and the second the correlated uncertainty.

Bin averaged hadron level differential cross section for diffractive dijet production as a function of the ET of jet 1. The first systematic error is the uncorrelated and the second the correlated uncertainty.

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Prompt Photons in Photoproduction at HERA

The H1 collaboration Aaron, F.D. ; Aldaya Martin, M. ; Alexa, C. ; et al.
Eur.Phys.J.C 66 (2010) 17-33, 2010.
Inspire Record 835534 DOI 10.17182/hepdata.56856

The production of prompt photons is measured in the photoproduction regime of electron-proton scattering at HERA. The analysis is based on a data sample corresponding to a total integrated luminosity of 340 pb^-1 collected by the H1 experiment. Cross sections are measured for photons with transverse momentum and pseudorapidity in the range 6 < Et < 15 GeV and -1.0 < eta < 2.4, respectively. Cross sections for events with an additional jet are measured as a function of the transverse energy and pseudorapidity of the jet, and as a function of the fractional momenta x_gamma and x_p carried by the partons entering the hard scattering process. The correlation between the photon and the jet is also studied. The results are compared with QCD predictions based on the collinear and on the k_T factorisation approaches.

17 data tables

Measured inclusive prompt photon cross section in the defined phase space.

Measured prompt photon plus jet cross section in the defined phase space.

Bin averaged differential cross section as a function of ET in the defined phase space.

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Study of Charm Fragmentation into $D^{*\pm}$ Mesons in Deep-Inelastic Scattering at HERA

The H1 collaboration Aaron, F.D. ; Alexa, C. ; Andreev, V. ; et al.
Eur.Phys.J.C 59 (2009) 589-606, 2009.
Inspire Record 792603 DOI 10.17182/hepdata.45316

The process of charm quark fragmentation is studied using $D^{*\pm}$ meson production in deep-inelastic scattering as measured by the H1 detector at HERA. Two different regions of phase space are investigated defined by the presence or absence of a jet containing the $D^{*\pm}$ meson in the event. The parameters of fragmentation functions are extracted for QCD models based on leading order matrix elements and DGLAP or CCFM evolution of partons together with string fragmentation and particle decays. Additionally, they are determined for a next-to-leading order QCD calculation in the fixed flavour number scheme using the independent fragmentation of charm quarks to $D^{*\pm}$ mesons.

20 data tables

Normalised D*+- cross section as a function of zJet for the D*+- jet sample.

Normalised D*+- cross section as a function of zHem for the D*+- jet sample.

Normalised D*+- cross section, corrected to the parton level, as a function of zJet for the D*+- jet sample.

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