Barker, A.R.
Single Differential Cross Section
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$K^- p$ and $\bar{p} p$ Elastic Scattering at 10.1-{GeV}/$c$

Berglund, A. ; Buran, T. ; Carlson, P.J. ; et al.
Nucl.Phys.B 176 (1980) 346-354, 1980.
Inspire Record 133174 DOI 10.17182/hepdata.34457

The differential cross sections for K − p and p p elastic scattering have been measured over the range of four-momentum transfer squared 0.18<− t <3.3 (GeV/ c ) 2 . The K − p data decrease smoothly as a function of − t , whereas, the p p data shows a break at − t = 0.6 (GeV/ c ) 2 followed by a fast drop to − t ≅ 1.6 (GeV/ c ) 2 where the differential cross section levels off and stays constant out to − t = 3 (GeV/ c ) 2 .

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
$\Lambda$ Production in $e^+ e^-$ Annihilation at 29-{GeV}

de la Vaissiere, C. ; Luth, V. ; Abrams, G.S. ; et al.
Phys.Rev.Lett. 54 (1985) 2071-2074, 1985.
Inspire Record 209198 DOI 10.17182/hepdata.20378

The production of Λ hyperons in e+e− annihilation has been measured as a function of their total momenta, transverse momenta, and the event thrust. The total production rate is 0.213±0.012±0.018 Λ or Λ¯ per hadronic event. The observation of correlations in rapidity and angles for events with two detected Λ decays supports fragmentation models with local baryon-number compensation.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


rivet Analysis
$\eta$ and $\eta^\prime$ Production in $e^+ e^-$ Annihilation at 29-{GeV}: Indications for the $D(s$)+- Decays Into $\eta \pi^\pm$ and $\eta^\prime \pi^\pm$

Wormser, G. ; Abrams, G.S. ; Amidei, D. ; et al.
Phys.Rev.Lett. 61 (1988) 1057, 1988.
Inspire Record 261194 DOI 10.17182/hepdata.20080

η production has been investigated by the Mark II collaboration at the SLAC e+e− storage ring PEP. η particles are reconstructed by their γγ decay mode. The η fragmentation function has been measured and found to be in good agreement with the Lund-model prediction. η′ production has been measured for the first time in high-energy e+e− annihilation. There is evidence at the 3σ level for Ds± decay into ηπ± and η′π±.

4 data tables
Table 1

Numerical values supplied by G.Wormser.

Table 2

Z = 0.0 point extrapolated using LUND fragmentation model.

Table 3

Z = 0.0 point extrapolated using LUND fragmentation model.

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A Global determination of alpha-s (M(z0)) at LEP

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 55 (1992) 1-24, 1992.
Inspire Record 333079 DOI 10.17182/hepdata.14606

The value of the strong coupling constant,$$\alpha _s (M_{Z^0 } )$$, is determined from a study of 15 d

16 data tables
Table 1

Differential jet mass distribution for the heavier jet using method T. The data are corrected for the finite acceptance and resolution of the detector and for initial state photon radiation.

Table 2

Differential jet mass distribution for the jet mass difference using methodT. The data are corrected for the finite acceptance and resolution of the detec tor and for initial state photon radiation.

Table 3

Differential jet mass distribution for the heavier jet using method M. The data are corrected for the finite acceptance and resolution of the detector and for initial state photon radiation.

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A Measurement of energy correlations and a determination of alpha-s (M2 (Z0)) in e+ e- annihilations at s**(1/2) = 91-GeV

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, J. ; et al.
Phys.Lett.B 252 (1990) 159-169, 1990.
Inspire Record 298707 DOI 10.17182/hepdata.29525

From an analysis of multi-hadron events from Z 0 decays, values of the strong coupling constant α s ( M 2 Z 0 )=0.131±0.006 (exp)±0.002(theor.) and α s ( M z 0 2 ) = −0.009 +0.007 (exp.) −0.002 +0.006 (theor.) are derived from the energy-energy correlation distribution and its asymmetry, respectively, assuming the QCD renormalization scale μ = M Z 0 . The theoretical error accounts for differences between O ( α 2 s ) calculations. A two parameter fit Λ MS and the renormalization scale μ leads to Λ MS =216±85 MeV and μ 2 s =0.027±0.013 or to α s ( M 2 Z 0 )=0.117 +0.006 −0.008 (exp.) for the energy-energy correlation distribution. The energy-energy correlation asymmetry distribution is insensitive to a scale change: thus the α s value quoted above for this variable includes the theoretical uncertainty associated with the renormalization scale.

3 data tables
Table 1

Data are at the hadron level, unfolded for initial-state radiation and for detector acceptance and resolution. Note that the systematic errors between bins are correlated.

Table 2

Alpha-s determined from the EEC measurements. The systematic error is an error in the theory.

Table 3

Alpha-s determined from the AEEC measurements. The systematic error is an error in the theory.


A Measurement of single and double prompt photon production at the CERN anti-p p collider

The UA2 collaboration Alitti, J. ; Ambrosini, G. ; Ansari, R. ; et al.
Phys.Lett.B 288 (1992) 386-394, 1992.
Inspire Record 336186 DOI 10.17182/hepdata.29113

A measurement of the cross-sections for single and double prompt photon production in p p interactions at s = 630 GeV is presented. The data sample corresponds to an integrated luminosity of 13.2 pb −1 . The results are in good agreement with the predictions of perturbative QCD. The signal from double prompt photon production has a statistical significance of 4.3 standard deviations.

2 data tables
Table 1

There is an overall systematic error of 9 pct not included in the table.

Table 2

Errors quoted include statistical and all PT dependent systematic uncertainties. There is in addition a 6.8 pct overall normalization uncertainty.


A Search for the Top and $b^\prime$ Quarks in Hadronic $\Z^0$ Decays

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, J. ; et al.
Phys.Lett.B 236 (1990) 364-374, 1990.
Inspire Record 283784 DOI 10.17182/hepdata.29702

We report on a search for new quarks in hadronic Z° decays. From the event shape analysis of a data sample containing 2185 multihadronic annihilation events, we observe no evidence for the top or b' quarks. We derive limits for the top and b' quark masses under the assumption of various possible standard model and non-standard model decay schemes. Our search is sensitive to quark masses larger than 23 GeV/ c 2 ; it yields the following lower limits at a 95% confidence level: 44.5 GeV/ c 2 for the top quark mass and 45.2 GeV/ c 2 for the b′ quark mass.

1 data table
Table 1

Measured event shape distributions - uncorrected.


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 Three Jet Events at the {CERN} $\bar{p} p$ Collider

The UA2 collaboration Appel, J.A. ; Bagnaia, P. ; Banner, M. ; et al.
Z.Phys.C 30 (1986) 341, 1986.
Inspire Record 219453 DOI 10.17182/hepdata.15897

The UA2 experiment, running at the CERN SPS\(\bar pp\) Collider, has performed a study of events containing three hard jets in the final state. The angular distributions of the three jets show evidence for gluon bremsstrahlung, in good agreement with a QCD model to leading order in the strong coupling constant αs. The yield of three-jet events relative to that of two-jet events provides a measure of the strong coupling constant: ;3K3/K2=0.23±0.01±0.04, whereK2 andK3 represent the contributions arising from higher order corrections in α3 to the two- and three-jet exclusive cross-sections. A detailed discussion of the systematic and theoretical uncertainties is given.

1 data table
Table 1

No description provided.


A Study of multi - jet events at the CERN anti-p p collider and a search for double parton scattering

The UA2 collaboration Alitti, J. ; Ambrosini, G. ; Ansari, R. ; et al.
Phys.Lett.B 268 (1991) 145-154, 1991.
Inspire Record 317817 DOI 10.17182/hepdata.29361

A study of events containing at least four high transverse momentum jets and a search for double parton scattering (DPS) have been performed using data collected with the UA2 detector at the CERN p p Collider (√ s =630 GeV). The results are in good agreement with leading order QCD calculations. A value of σ DPS <0.82 nb at 95% confidence level (CL) is obtained for the DPS cross section.

3 data tables
Table 1

Data requested from authors.

Table 2

Uncorrected cross sections.

Table 3

Upper limit to DPS contribution to 4JET production.