Nelson, C.A., Jr.
Double Differential Cross Section
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PHOTOPRODUCTION OF eta MESONS AT 9.7-GeV

Nelson, C.A., Jr. ; Abramson, J. ; Andrews, D.E. ; et al.
Phys.Rev.D 19 (1979) 1931, 1979.
Inspire Record 132567 DOI 10.17182/hepdata.24307

Inclusive η photoproduction has been studied at 9.7 GeV, on hydrogen and deuterium targets. A simple, parameter-free ρ0-dominance model adequately fits the forward cross sections, but overestimates the cross section at large momentum transfer.

1 data table
Table 1

No description provided.


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.


rivet Analysis
Production characteristics of K0 and light meson resonances in hadronic decays of the Z0

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Z.Phys.C 65 (1995) 587-602, 1995.
Inspire Record 377487 DOI 10.17182/hepdata.48348

An analysis of inclusive production of K0 and the meson resonances K*±(892), ρ0(770),f0(975) andf2(1270) in hadronic decays of the Z0 is presented, based on about 973,000 multihadronic events collected by the DELPHI detector at LEP during 1991 and 1992. Overall multiplicities have been determined as 1.962±0.060 K0 mesons, 0.712±0.067 K*±(892) and 1.21±0.15ρ0(770) per hadronic Z0 decay. The average multiplicities off0(975) for scaled momentum,xp, in the range 0.05≤xp≤0.6 and off2(1270) for 0.05≤xp≤1.0 are 0.098±0.016 and 0.170±0.043 respectively. Thef0(975) and ρ0(770)xp-spectra have similar shapes. Thef2(1270)/ρ0(770) ratio increases withxp. The average multiplicities and the differential cross sections are compared with the JETSET Parton Shower model. The model with default parameters fails to reproduce the experimental K0 momentum spectrum at low momentum, describes the K*±(892) and ρ0(770)xp-spectrum shapes, but significantly overestimates their production rates.

13 data tables
Table 1

Average multiplicity per hadronic event. Extrapolation to the full X range using the X-shape predicted by JETSET 7.4 PS model.

Table 2

Average multiplicity per hadronic event. Extrapolation to the full X range using the X-shape predicted by JETSET 7.4 PS model.

Table 3

Average multiplicity per hadronic event. Extrapolation to the full X range using the X-shape predicted by JETSET 7.4 PS model.

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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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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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Measurement of Drell-Yan electron and muon pair differential cross-sections in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
Phys.Rev.D 49 (1994) R1-R6, 1994.
Inspire Record 355927 DOI 10.17182/hepdata.42543

We measure the Drell-Yan differential cross section d2σdMdy||y|<1 over the mass range 11<M<150 GeV/c2 using dielectron and dimuon data from p¯p collisions at a center-of-mass energy of s=1.8 TeV. Our results show the 1M3 dependence that is expected from the naive Drell-Yan model. In comparison to the predictions of recent QCD calculations we find our data favor those parton distribution functions with the largest quark contributions in the x interval 0.006 to 0.03.

3 data tables
Table 1

Dielectron differential cross section.

Table 2

Dimuon differential cross section.

Table 3

Drell-Yan differential cross section for combined dielectron and dimuon data. Error includes both statistics and systematics.


Inclusive charged particle cross-sections in photoproduction at HERA

The H1 collaboration Abt, I. ; Ahmed, T. ; Andreev, V. ; et al.
Phys.Lett.B 328 (1994) 176-186, 1994.
Inspire Record 372256 DOI 10.17182/hepdata.45105

Cross sections are presented for the inclusive production of charged particles measured in electron-proton collisions at low Q 2 with the H1 detector at HERA. The transverse momentum distribution extends up to 8 GeV/ c . Its shape is found to be harder than that observed in p p collisions at comparable centre-of-mass energies √S γp ≈ √S p p ≈ 200 GeV , and also harder than in γp collisions at lower energies √ S γp ≈ 18 GeV. Results from quantum chromodynamics (QCD) calculations agree with the measured transverse momentum and pseudorapidity cross sections.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


A Precision measurement of the prompt photon cross-section in p anti-p collisions at S**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amidei, D. ; et al.
Phys.Rev.Lett. 73 (1994) 2662-2666, 1994.
Inspire Record 375582 DOI 10.17182/hepdata.19680

A prompt photon cross section measurement from the Collider Detector at Fermilab experiment is presented. Detector and trigger upgrades, as well as 6 times the integrated luminosity compared with our previous publication, have contributed to a much more precise measurement and extended PT range. As before, QCD calculations agree qualitatively with the measured cross section, but the data has a steeper slope than the calculations.

1 data table
Table 1

Note that the sytematic uncertainties are approximately 100 pct correlated bin to bin.


Upsilon production in p anti-p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amendolia, S.R. ; et al.
Phys.Rev.Lett. 75 (1995) 4358, 1995.
Inspire Record 398187 DOI 10.17182/hepdata.42349

We report on measurements of the ϒ(1S), ϒ(2S), and ϒ(3S) differential, (d2σdPtdy)y=0, and integrated cross sections in pp¯ collisions at s=1.8 TeV using a sample of 16.6 ± 0.6 pb−1 collected by the Collider Detector at Fermilab. The three resonances were reconstructed through the decay ϒ→μ+μ−. Comparison is made to a leading order QCD prediction.

7 data tables
Table 1

SIG*Br(UPSI --> MU+ MU-).

Table 2

SIG*Br(UPSI --> MU+ MU-).

Table 3

SIG*Br(UPSI --> MU+ MU-).

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Comparison of the isolated direct photon cross-sections in p anti-p collisions at s**(1/2) = 1.8-TeV and s**(1/2) = 0.63-TeV

The CDF collaboration Acosta, D. ; Affolder, T. ; Akimoto, H. ; et al.
Phys.Rev.D 65 (2002) 112003, 2002.
Inspire Record 581379 DOI 10.17182/hepdata.42882

We have measured the cross sections $d^2\sigma/dP_T d\eta$ for production of isolated direct photons in \pbarp collisions at two different center-of-mass energies, 1.8 TeV and 0.63 TeV, using the Collider Detector at Fermilab (CDF). The normalization of both data sets agree with the predictions of Quantum Chromodynamics (QCD) for photon transverse momentum ($P_T$) of 25 GeV/c, but the shapes versus photon $P_T$ do not. These shape differences lead to a significant disagreement in the ratio of cross sections in the scaling variable $x_T (\equiv 2P_T/\sqrt{s}$). This disagreement in the $x_T$ ratio is difficult to explain with conventional theoretical uncertainties such as scale dependence and parton distribution parameterizations.

2 data tables
Table 1

The 1800 GeV isolated photon cross section. The systematic (DSYS) uncertainties include the normalisation uncertainties which are 100 PCT correlated bin tobin.

Table 2

The 630 GeV isolated photon cross section. The systematic (DSYS) uncertainties include the normalisation uncertainties which are 100 PCT correlated bin to bin.