HEPData Search

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A Prompt photon cross-section measurement in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M. ; Amidei, D. ; et al.

Phys.Rev.D 48 (1993) 2998-3025, 1993.

Inspire Record 353026 DOI 10.17182/hepdata.22677

The first prompt photon measurement from the CDF experiment at the Fermilab pp¯ Collider is presented. Two independent methods are used to measure the cross section: one for high transverse momentum (PT) and one for lower PT. Comparisons to various theoretical calculations are shown. The cross section agrees qualitatively with QCD calculations but has a steeper slope at low PT.

4 data tables

Table 1

Cross section using profile method and an isolation cut of 2 GeV in a cone around the photon. There is an additional 27 pct systematic uncertainty in addition to the PT dependent systematic errors shown in the table.

Table 2

Cross section using conversion method and an isolation cut of 2 GeV in a cone around the photon. There is an additional +32,-46 pct systematic uncertainty in addition to the PT dependent systematic errors shown in the table.

Table 3

Cross section using profile method and an isolation cut of 15 pct of the photon PT in a cone around the photon. There is an additional 29 pct systematic uncertainty in addition to the PT dependent systematic errors shown in the table.

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Inclusive electron nucleus scattering at high momentum transfer

Day, D.B. ; McCarthy, J.S. ; Meziani, Z.E. ; et al.

Phys.Rev.C 48 (1993) 1849-1863, 1993.

Inspire Record 365224 DOI 10.17182/hepdata.6186

The response function of nuclei in the quasielastic region at large momentum transfer (q≤10 fm−1) is measured for a series of nuclei, He4, C12, Al27, Fe56, and Au197, up to large values of the Bjorken scaling variables x<2.5.

23 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Production of direct photons and neutral mesons at large transverse momenta by pi- and p beams at 500-GeV/c

The FERMILAB-E706 collaboration Alverson, G. ; Baker, W.F. ; Ballocchi, G. ; et al.

Phys.Rev.D 48 (1993) 5-28, 1993.

Inspire Record 353153 DOI 10.17182/hepdata.22583

We present results from the initial run of Fermilab experiment E706. The data include incident π− and p beams at 500 GeV/c on Be and Cu targets, and span the kinematic ranges of transverse momentum and rapidity of 3.5≤pT≤10 GeV/c and −0.7≤yc.m.≤0.7, respectively. We have measured cross sections for π0 and direct-photon production, as well as the ηπ0 production ratio. From the data on Be and Cu, we have extracted the nuclear dependence of π0 production, parametrized as Aα. The cross sections are compared with next-to-leading-log QCD predictions for different choices of the QCD momentum scales and several sets of parton distribution functions.

10 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Measurement of inclusive eta production in hadronic decays of the Z0

The L3 collaboration Adriani, O. ; Aguilar-Benitez, M. ; Ahlen, S. ; et al.

Phys.Lett.B 286 (1992) 403-412, 1992.

Inspire Record 336180 DOI 10.17182/hepdata.29161

We present a study of the inclusive η production based on 300 000 hadronic Z 0 decays. The measured inclusive momentum distribution can be reproduced by parton shower Monte Carlo programs and also by an analytical QCD calculation. Comparing our results with low energy e + e − data, we find that QCD describes both the shape and the energy evolution of the η spectrum. The comparison of η production rates in quark- and gluon-enriched jet samples does not show statistically significant evidence for more abundant production of η mesons in gluon fragmentation.

2 data tables

Table 1

Differential cross section for inclusive eta production, normalized to the total hadronic cross section.

Table 2

Differential cross section for inclusive eta production, normalized to the total hadronic cross section.

Measurement of the isolated prompt photon cross-sections in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Apollinari, G. ; et al.

Phys.Rev.Lett. 68 (1992) 2734-2738, 1992.

Inspire Record 333081 DOI 10.17182/hepdata.19869

We present a measurement of the cross section for production of isolated prompt photons in p¯p collisions at √s =1.8 TeV. The cross section, measured as a function of transverse momentum (PT), agrees qualitatively with QCD calculations but has a steeper slope at low PT.

1 data table

Table 1

Additional normalization systematic uncertainty of 27 pct for first eleven entries, and +32 pct(-46 pct) for last four entries.

Investigation of inclusive production of K0 and K*0 (892) mesons in K+ A interaction at 11.2-GeV

The Hyperon collaboration Akimenko, S.A. ; Belousov, V.I. ; Kolosov, V.N. ; et al.

Z.Phys.C 56 (1992) 537-546, 1992.

Inspire Record 348109 DOI 10.17182/hepdata.14531

Inclusive production ofK0 andK* (892)0 mesons inK+A-interactions (A=Be, Cu, Pb) at the energy 11.2 GeV has been investigated to study hadronisation of the leading$\bar s$-quark; the results are presented. Double differential cross sections d2σ/dxfdpt2 were measured in the region of incident particle fragmentation (0.4≦xf≦1,pt≦0.5 GeV/c). The experimental data obtained were analysed on the basis of the Lund model FRITIOF and a quark-gluon model that takes into account colour screening and hadron formation length effects. The experimental data confirm the picture of hadronisation of the leading$\bar s$-quark developed in the latter model.

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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A Study of K0(s) production in Z0 decays

The OPAL collaboration Alexander, G. ; Allison, J. ; Allport, P.P. ; et al.

Phys.Lett.B 264 (1991) 467-475, 1991.

Inspire Record 316151 DOI 10.17182/hepdata.29375

The production of K 0 mesons in e + e − interactions at center of mass energies in the region of the Z 0 mass has been investigated with the OPAL detector at LEP. The rate is found to be 2.10±0.02±0.14 K 0 , Z 0 per hadronic event. The predictions from the JETSET and HERWIG generators agree very well with both the rate and the scale invariant cross section (1/σ had β) (dσ/d x E ) for K 0 production. Comparisons of the inclusive momentum spectrum with predictions of an analytical QCD formula and with data from lower center of mass energies are presented.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

K0 multiplicity per hadronic event.

A Study of coherence of soft gluons in hadron jets

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, J. ; et al.

Phys.Lett.B 247 (1990) 617-628, 1990.

Inspire Record 297564 DOI 10.17182/hepdata.49561

We study the inclusive momentum distribution of charged particles in multihadronic events produced in e + e − annihilations at E CM ∼ M (Z 0 ). We find agreement with the analytical formulae for gluon production that include the phenomena of soft gluon interference. Using data from CM energies between 14 and 91 GeV, we study the dependence of the inclusive momentum distribution on the centre of momentum energy. We find that the analytical formulae describe the data over the entire energy range. Both the momentum distribution at a fixed energy and the change with energy are described by QCD shower Monte Carlo's which include either coherent gluon branchings or string fragmentation. Simple incoherent models with independent fragmentation fail to reproduce the energy dependence and momentum spectra.

1 data table

Table 1

Statistical errors only. Overall systematic error of 5%.