Date

Inclusive upsilon and pi0 production in pbar p interactions at 32 GeV/c

Poiret, C. ; Scory, M. ; Windmolders, R. ; et al.
Z.Phys.C 7 (1981) 283-287, 1981.
Inspire Record 1385259 DOI 10.17182/hepdata.1

The inclusive π0 and γ production is studied in a\(\bar PP\) experiment at 32.1 GeV/c performed in the Mirabelle bubble chamber with a sensitivity of ∼2.7 events/μb. Total and topological π0 cross sections are presented. The π0 and γ longitudinal and transverse momentum distributions are obtained and compared with\(\bar PP\) data at 22.4 GeV/c andK ± P data at 32.1 GeV/c. The inclusive π0 distributions are also compared to those obtained for charged pions in the same experiment.

5 data tables

No description provided.

No description provided.

No description provided.

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Charged Particle Production in High Q2 Deep-Inelastic Scattering at HERA

The H1 collaboration Aaron, F.D. ; Aktas, A. ; Alexa, C. ; et al.
Phys.Lett.B 654 (2007) 148-159, 2007.
Inspire Record 753349 DOI 10.17182/hepdata.45525

The average charged track multiplicity and the normalised distribution of the scaled momentum, $\xp$, of charged final state hadrons are measured in deep-inelastic $\ep$ scattering at high $Q^2$ in the Breit frame of reference. The analysis covers the range of photon virtuality $100 < Q^2 < 20 000 \GeV^{2}$. Compared with previous results presented by HERA experiments this analysis has a significantly higher statistical precision and extends the phase space to higher $Q^{2}$ and to the full range of $\xp$. The results are compared with $e^+e^-$ annihilation data and with various calculations based on perturbative QCD using different models of the hadronisation process.

11 data tables

Average values of Q and X (plus errors) for the different Q**2 ranges.

Average charged hadron multiplicity as a function of Q**2.

Normalised distribution of the scaled momentum as a function of Q**2 in the X range 0 to 0.02.

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Multiplicity structure of the hadronic final state in diffractive deep-inelastic scattering at HERA.

The H1 collaboration Adloff, C. ; Anderson, M. ; Andreev, V. ; et al.
Eur.Phys.J.C 5 (1998) 439-452, 1998.
Inspire Record 469495 DOI 10.17182/hepdata.44363

The multiplicity structure of the hadronic system X produced in deep-inelastic processes at HERA of the type ep -> eXY, where Y is a hadronic system with mass M_Y< 1.6 GeV and where the squared momentum transfer at the pY vertex, t, is limited to |t|<1 GeV^2, is studied as a function of the invariant mass M_X of the system X. Results are presented on multiplicity distributions and multiplicity moments, rapidity spectra and forward-backward correlations in the centre-of-mass system of X. The data are compared to results in e+e- annihilation, fixed-target lepton-nucleon collisions, hadro-produced diffractive final states and to non-diffractive hadron-hadron collisions. The comparison suggests a production mechanism of virtual photon dissociation which involves a mixture of partonic states and a significant gluon content. The data are well described by a model, based on a QCD-Regge analysis of the diffractive structure function, which assumes a large hard gluonic component of the colourless exchange at low Q^2. A model with soft colour interactions is also successful.

10 data tables

The multiplicity moment MULT as a function of the mass of the charged hadron system in the full phase space and separately in the forward and backward hemispheres.

The multiplicity moment DISPERSION as a function of the mass of the charged hadron system in the full phase space and separately in the forward and backward hemispheres.

The multiplicity moment R2 as a function of the mass of the charged hadron system in the full phase space and separately in the forward and backward hemispheres.

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Evolution of e p fragmentation and multiplicity distributions in the Breit frame.

The H1 collaboration Adloff, C. ; Aid, S. ; Anderson, M. ; et al.
Nucl.Phys.B 504 (1997) 3-23, 1997.
Inspire Record 445116 DOI 10.17182/hepdata.44587

Low x deep-inelastic ep scattering data, taken in 1994 at the H1 detector at HERA, are analysed in the Breit frame of reference. The evolution of the peak and width of the current hemisphere fragmentation function is presented as a function of Q and compared with e+e- results at equivalent centre of mass energies. Differences between the average charged multiplicity and the multiplicity of e+e- annihilations at low energies are analysed. Invariant energy spectra are compared with MLLA predictions. Distributions of multiplicity are presented as functions of Bjorken-x and Q^2, and KNO scaling is discussed.

25 data tables

The current hemisphere fragmentation as a function of XP in the Breit frame.

The current hemisphere fragmentation as a function of LN(1/XP) in the Breitframe.

Current hemisphere fragmentation as a function of Q for the XP range 0.02 to 0.05, to show scaling violations.

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Charged particle multiplicities in deep inelastic scattering at HERA.

The H1 collaboration Aid, S. ; Anderson, M. ; Andreev, V. ; et al.
Z.Phys.C 72 (1996) 573-592, 1996.
Inspire Record 422230 DOI 10.17182/hepdata.44709

Using the H1 detector at HERA, charged particle multiplicity distributions in deep inelastic ep scattering have been measured over a large kinematical region. The evolution with $W$ and $Q~2$ of the multiplicity distribution and of the multiplicity moments in pseudorapidity domains of varying size is studied in the current fragmentation region of the hadronic centre-of-mass frame. The results are compared with data from fixed target lepton-nucleon interactions, $e~+e~-$ annihilations and hadron-hadron collisions as well as with expectations from QCD based parton models. Fits to the Negative Binomial and Lognormal distributions are presented.

12 data tables

Fully corrected multiplicity distributions. Note that the value of P0 in the 1 to 5 pseudorapidity region is not measured but taken from the reweighted DJANGO 6.0 Monte Carlo generator.

Fully corrected multiplicity distributions. Note that the value of P0 in the 1 to 5 pseudorapidity region is not measured but taken from the reweighted DJANGO 6.0 Monte Carlo generator.

Fully corrected multiplicity distributions. Note that the value of P0 in the 1 to 5 pseudorapidity region is not measured but taken from the reweighted DJANGO 6.0 Monte Carlo generator.

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Strangeness production in deep-inelastic positron proton scattering at HERA.

The H1 collaboration Aid, S. ; Anderson, M. ; Andreev, V. ; et al.
Nucl.Phys.B 480 (1996) 3-34, 1996.
Inspire Record 421030 DOI 10.17182/hepdata.44711

Measurements are presented of $K~0$ meson and $\Lambda$ baryon production in deep-inelastic positron-proton scattering (DIS) in the kinematic range $10 < Q~2 < 70\,$GeV$~2$ and $10~{-4} < x < 10~{-2}$. The measurements, obtained using the H1 detector at the HERA collider, are discussed in the light of possible mechanisms for increased strangeness production at low Bjorken-$x$. Comparisons of the $x_F$ spectra, where $x_F$ is the fractional longitudinal momentum in the hadronic centre-of-mass frame, with results from electron-positron annihilation are made. The $x_F$ spectra and the $K~0$ ``seagull'' plot are compared with previous DIS results. The mean $K~0$ and $\Lambda$ multiplicities are studied as a function of the centre-of-mass energy $W$ and are observed to be consistent with a logarithmic increase with $W$ when compared with previous measurements. A comparison of the levels of strangeness production in diffractive and non-diffractive DIS is made. An upper limit of $0.9\,$nb, at the $95\%$ confidence level, is placed on the cross-section for QCD instanton induced events.

5 data tables

The XL distribution for K0 particles.

The XL distribution for LAMBDA particles.

Corrected Mean PT**2 for K0 production RE = E+ P --> E+ K0 X.

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Nuclear-target diffraction dissociation in pi+ and K+ collisions with Au and Al at 250-GeV/c.

The EHS/NA22 collaboration Agababyan, N.M. ; Ataian, M.R. ; Charlet, M. ; et al.
Z.Phys.C 72 (1996) 65-70, 1996.
Inspire Record 419049 DOI 10.17182/hepdata.14252

An analysis of theA-dependence of the target-diffractive cross-section is presented. Data on thet-dependence of the cross section are fitted in the usual exponential form. The mean multiplicity of negative particles produced diffractively is found not to be sensitive to the nuclear mass. TheA-dependence of the emitted proton multiplicity and the angular distributions of the produced charged particles suggest re-scattering of the emitted particles on other nucleons of the nucleus. All these facts are compared with results obtained by Monte-Carlo simulation according to a two-component Dual Parton Model.

6 data tables

For target-diffractive cross-section.

For target-diffractive cross-section.

Multiplicities for the diffractive system.

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A Study of the fragmentation of quarks in e- p collisions at HERA

The H1 collaboration Aid, S. ; Andreev, V. ; Andrieu, B. ; et al.
Nucl.Phys.B 445 (1995) 3-21, 1995.
Inspire Record 394793 DOI 10.17182/hepdata.44978

Deep inelastic scattering (DIS) events, selected from 1993 data taken by the H1 experiment at HERA, are studied in the Breit frame of reference. The fragmentation function of the quark is compared with those of \ee data. It is shown that certain aspects of the quarks emerging from within the proton in \ep interactions are essentially the same as those of quarks pair-created from the vacuum in \ee annihilation. The measured area, peak position and widthof the fragmentation function show that the kinematic evolution variable, equivalent to the \ee squared centre of mass energy, is in the Breit frame the invariant square of the four-momentum transfer. We comment on the extent to which we have evidence for coherence effects in parton showers.

6 data tables

Distribution of the cosine of the Breit frame polar angle for data with the Breit frame energy flow selection. Statistical errors only.

Distribution of the cosine of the Breit frame polar angle for data before the Breit frame energy flow selection. Statistical errors only.

The fragmentation function for the current hemisphere of the Breit frame. Data are Breit frame energy flow selected only. Statistical errors only.

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Rescattering probed by the emission of slow target associated particles in high-energy heavy ion interactions

The EMU01 collaboration Adamovich, M.I ; Aggarwal, M.M ; Alexandrov, Y.A ; et al.
Phys.Lett.B 363 (1995) 230-236, 1995.
Inspire Record 406952 DOI 10.17182/hepdata.28438

In this letter the distribution of slow target associated particles emitted in Au + Emulsion interactions at 11.6 A GeV/ c is studied. The three models RQMD, FRITIOF and VENUS are used for comparisons and especially their treatment of rescattering is investigated.

6 data tables

No description provided.

PROJECTILE ASSOCIATED HE-FRAGMENTS.

No description provided.

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Si-28 (S-32) fragmentation at 3.7-A/GeV, 14.6-A/GeV and 200-A/GeV

The EMU1 collaboration Adamovich, M.I. ; Aggarwal, M.M. ; Alexandrov, Y.A. ; et al.
Z.Phys.A 351 (1995) 311-316, 1995.
Inspire Record 407109 DOI 10.17182/hepdata.16506

The fragmentation topology of28Si at 3.7A GeV and 14.6A GeV and32S at 200A GeV in reactions with emulsion nuclei is presented. The fragmentation cross sections are very similar at all three energies. A statistical percolation model can qualitatively describe the data forZ≥ 6. The He production is underestimated and the 3 ≤Z ≤ 5 fragments overestimated by this model.

6 data tables

JINR.

BNL-815.

CERN-EMU-001.

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