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Measurement of the open-charm contribution to the diffractive proton structure function.

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Krakauer, D. ; et al.
Nucl.Phys.B 672 (2003) 3-35, 2003.
Inspire Record 624128 DOI 10.17182/hepdata.43831

Production of D*+/-(2010) mesons in diffractive deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 82 pb^{-1}. Diffractive events were identified by the presence of a large rapidity gap in the final state. Differential cross sections have been measured in the kinematic region 1.5 < Q^2 < 200 GeV^2, 0.02 < y < 0.7, x_{IP} < 0.035, beta < 0.8, p_T(D*+/-) > 1.5 GeV and |\eta(D*+/-)| < 1.5. The measured cross sections are compared to theoretical predictions. The results are presented in terms of the open-charm contribution to the diffractive proton structure function. The data demonstrate a strong sensitivity to the diffractive parton densities.

18 data tables

Total cross section for diffractive D*+- production in the stated kinematicregion.. The second DSYS uncertainty arises from the subtraction of the proton-dissociative background.

The differential cross section as a function of X(NAME=POMERON).

The differential cross section as a function of transverse momentum.

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Measurement of diffractive production of D*(2010)+- mesons in deep inelastic scattering at HERA.

The ZEUS collaboration Chekanov, S. ; Krakauer, D. ; Magill, S. ; et al.
Phys.Lett.B 545 (2002) 244-260, 2002.
Inspire Record 588104 DOI 10.17182/hepdata.46583

Diffractive production of D*+-(2010) mesons in deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 44.3 pb-1. Diffractive charm production is identified by the presence of a large rapidity gap in the final state of events in which a D*+-(2010) meson is reconstructed in the decay channel D*+ -> (D0 -> K-pi+) pi+ (+ charge conjugate). Differential cross sections when compared with theoretical predictions indicate the importance of gluons in such diffractive interactions.

9 data tables

Measurment of total diffractive cross section and ratio to inclusive DIS cross section.

Ratio of diffractive to inclusive D*+- production w.r.t. Q**2.

Ratio of diffractive to inclusive D*+- production w.r.t. W.

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Inelastic leptoproduction of J / psi mesons at HERA

The H1 collaboration Adloff, C. ; Andreev, V. ; Andrieu, B. ; et al.
Eur.Phys.J.C 25 (2002) 41-53, 2002.
Inspire Record 586978 DOI 10.17182/hepdata.46581

The leptoproduction of J/psi mesons is studied in inelastic reactions for four momentum transfers 2

23 data tables

J/PSI leptoproduction differential cross section as a function of Q**2.

J/PSI leptoproduction differential cross section as a function of Z.

J/PSI leptoproduction differential cross section as a function of W.

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Measurement of D*+- meson production and F2(c) in deep inelastic scattering at HERA.

The H1 collaboration Adloff, C. ; Andreev, V. ; Andrieu, B. ; et al.
Phys.Lett.B 528 (2002) 199-214, 2002.
Inspire Record 561885 DOI 10.17182/hepdata.46834

The inclusive production of D^{*+-}(2010) mesons in deep-inelastic scattering is studied with the H1 detector at HERA. In the kinematic region 11.5 GeV and |\eta_(D^*)|<1.5. Single and double differential inclusive D^(*+-) meson cross sections are compared to perturbative QCD calculations in two different evolution schemes. The charm contribution to the proton structure, F_2^c(x,Q^2), is determined by extrapolating the visible charm cross section to the full phase space. This contribution is found to rise from about 10% at Q^2 = 1.5 GeV^2 to more than 25% at Q^2 = 60 GeV^2 corresponding to x values ranging from 5*10^(-5) to 3*10^(-3)$.

14 data tables

The inclusive cross section for D*+- production. The second DSYS error is related to the changes in efficiency obtained by using different Monte Carlo generators and varying the model parameters.

Single differential visible cross section as a function of W.

Single differential visible cross section as a function of PT.

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Diffractive jet production in deep inelastic e+ p collisions at HERA

The H1 collaboration Adloff, C. ; Andreev, V. ; Andrieu, B. ; et al.
Eur.Phys.J.C 20 (2001) 29-49, 2001.
Inspire Record 539087 DOI 10.17182/hepdata.46939

A measurement is presented of dijet and 3-jet cross sections in low-|t| diffractive deep-inelastic scattering interactions of the type ep -> eXY, where the system X is separated by a large rapidity gap from a low-mass baryonic system Y. Data taken with the H1 detector at HERA, corresponding to an integrated luminosity of 18.0 pb^(-1), are used to measure hadron level single and double differential cross sections for 44 GeV. The energy flow not attributed to jets is also investigated. The measurements are consistent with a factorising diffractive exchange with trajectory intercept close to 1.2 and tightly constrain the dominating diffractive gluon distribution. Viewed in terms of the diffractive scattering of partonic fluctuations of the photon, the data require the dominance of qqbarg over qqbar states. Soft colour neutralisation models in their present form cannot simultaneously reproduce the shapes and the normalisations of the differential cross sections. Models based on 2-gluon exchange are able to reproduce the shapes of the cross sections at low x_pom values.

24 data tables

Average values, over the specified interval, of the differential hadron level dijet cross section as a function of Q**2.

Average values, over the specified interval, of the differential hadron level dijet cross section as a function of the average transverse momentum of the two jets in the c.m.frame.

Average values, over the specified interval, of the differential hadron level dijet cross section as a function of the average pseudorapidity of the two jets in the lab frame.

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Measurement of D*+- production and the charm contribution to F2 in deep inelastic scattering at HERA.

The ZEUS collaboration Breitweg, J. ; Chekanov, S. ; Derrick, M. ; et al.
Eur.Phys.J.C 12 (2000) 35-52, 2000.
Inspire Record 505056 DOI 10.17182/hepdata.43895

The production of D*+-(2010) mesons in deep inelastic scattering has been measured in the ZEUS detector at HERA using an integrated luminosity of 37 pb^-1. The decay channels D*+ -> D0 pi+(+c.c.), with D0 -> K- pi+ or D0 ->K- pi- pi+ pi+, have been used to identify the D mesons. The e+p cross section for inclusive D*+- production with 1

22 data tables

The measured cross section for D* production. The first is derived from theK2PI final state and the second from the K4PI final state.

The differential cross section w.r.t. Q**2 from the K2PI final state. The asymmetric errors are the quadratic sum of the statistical and systematic errors. The statistical errors are also shown separately.

The differential cross section w.r.t. X from the K2PI final state. The asymmetric errors are the quadratic sum of the statistical and systematic errors. The statistical errors are also shown separately.

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Charmonium production in deep inelastic scattering at HERA

The H1 collaboration Adloff, C. ; Andreev, V. ; Andrieu, B. ; et al.
Eur.Phys.J.C 10 (1999) 373-393, 1999.
Inspire Record 496430 DOI 10.17182/hepdata.44039

The electroproduction of J/psi and psi(2S) mesons is studied in elastic, quasi-elastic and inclusive reactions for four momentum transfers 2 < Q^2 < 80 GeV^2 and photon-proton centre of mass energies 25 < W < 180 GeV. The data were taken with the H1 detector at the electron proton collider HERA in the years 1995 to 1997. The total virtual photon-proton cross section for elastic J/psi production is measured as a function of Q^2 and W. The dependence of the production rates on the square of the momentum transfer from the proton (t) is extracted. Decay angular distributions are analysed and the ratio of the longitudinal and transverse cross sections is derived. The ratio of the cross sections for quasi-elastic psi(2S) and J/psi meson production is measured as a function of Q^2. The results are discussed in terms of theoretical models based upon perturbative QCD. Differential cross sections for inclusive and inelastic production of J/psi mesons are determined and predictions within two theoretical frameworks are compared with the data, the non-relativistic QCD factorization approach including colour octet and colour singlet contributions, and the model of Soft Colour Interactions.

17 data tables

Cross section for elastic J/PSI photoproduction in W bins.

Cross section for elastic J/PSI photoproduction in W bins.

Cross section for elastic J/PSI photoproduction in W bins.

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