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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Studies of QCD at e+ e- centre-of-mass energies between 91-GeV and 209-GeV.

The ALEPH collaboration Heister, A. ; Schael, S. ; Barate, R. ; et al.
Eur.Phys.J.C 35 (2004) 457-486, 2004.
Inspire Record 636645 DOI 10.17182/hepdata.12794

The hadronic final states observed with the ALEPH detector at LEP in ${\rm e}^ + {\rm e}^-$ annihilation

234 data tables

Mean charged particle multiplicities at different c.m. energies.

XP distribution at c.m. energy 133.0 GeV.

XP distribution at c.m. energy 161.0 GeV.

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QCD studies with e+ e- annihilation data at 130-GeV and 136-GeV.

The OPAL collaboration Alexander, G. ; Allison, John ; Altekamp, N. ; et al.
Z.Phys.C 72 (1996) 191-206, 1996.
Inspire Record 418007 DOI 10.17182/hepdata.47564

We have studied hadronic events produced at LEP at centre-of-mass energies of 130 and 136 GeV. Distributions of event shape observables, jet rates, momentum spectra and multiplicities are presented and compared to the predictions of several Monte Carlo models and analytic QCD calculations. From fits of event shape and jet rate distributions to\({\mathcal{O}}(\alpha _s^2 ) + NLLA\) QCD calculations, we determineαs(133 GeV)=0.110±0.005(stat.)±0.009(syst.). We measure the mean charged particle multiplicity 〈nch〉=23.40±0.45(stat.) ±0.47(syst.) and the position ζ0 of the peak in the ζp = ln(1/xp) distribution ζ0=3.94±0.05(stat.)±0.11(syst.). These results are compared to lower energy data and to analytic QCD or Monte Carlo predictions for their energy evolution.

23 data tables

Determination of alpha_s.

Multiplicity and high moments.

Tmajor distribution.

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Studies of QCD in e+ e- --> hadrons at E(cm) = 130-GeV and 136-GeV.

The ALEPH collaboration Buskulic, D. ; De Bonis, I. ; Decamp, D. ; et al.
Z.Phys.C 73 (1997) 409-420, 1997.
Inspire Record 421546 DOI 10.17182/hepdata.47802

None

8 data tables

Inclusive charged particle distribution as a function of XP.

Inclusive charged particle distribution as a function of rapidity (YRAP).

Inclusive charged particle distribution as a function of PT in the event plane.

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