Alexander, James
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rivet Analysis
Inclusive $K^0$ Production in $e^+ e^-$ Annihilation for 9.3-{GeV} $<\sqrt{s}<$ 31.6-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 104 (1981) 79-83, 1981.
Inspire Record 165122 DOI 10.17182/hepdata.6716

Results on inclusive K s 0 production in e + e − annihilation at mean center-of-mass energies of 9.4, 12.0 and 30 GeV are presented. The ratio R (K 0 ) = 2 σ (K s 0 )/ σ μμ rises from 3.10 ± 0.75 at √ s = 9.4 GeV to 5.6 ± 1.2 at √ s = 30 GeV, corresponding to an approximately constant K 0 /charged-particle ratio of 0.12 ± 0.02. A similar ratio for K 0 / charged particle is observed for direct hadronic decays of the ϒ.

7 data tables
Table 1

SYSTEMATIC ERROR INCLUDED.

Table 2

NUMBER OF K0 PER HADRONIC EVENT. AUTHORS ALSO USE MULTIPLICITY TO ESTIMATE NUMBER OF K0 PER CHARGED PARTICLE.

Table 3

INCLUDING EARLIER DATA.

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Inclusive and Semiinclusive $\rho^0$ Production in $\pi^+ / \pi^- / K^+ / P P$ Interactions at 147-{GeV}/$c$

Schouten, M. ; De Bock, H. ; Dziembowski, Z. ; et al.
Z.Phys.C 9 (1981) 93-104, 1981.
Inspire Record 170594 DOI 10.17182/hepdata.1419

In an experiment with the 30-inch Hybrid Spectrometer at Fermilab we have obtained the inclusive and semi-inclusive production cross sections of the ϱ0 meson using a conventional background subtraction technique. Production cross sections for the ϱ0 are derived as a function of the Feynman scaling variablex, and the transverse variablespt2 andEt=(pt2+M2)1/2. The longitudinal distributions are compared with the (1−x) dependence of the proton and meson valence quark structure functions, using various forms of recombination and fragmentation models. The transverse distributions are compared with thermodynamic models. We give density matrix elements for the ϱ0 production from pions in the extreme forward region.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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MEASUREMENT OF THE P P AND P D TOTAL CROSS-SECTIONS IN PURE TRANSVERSE SPIN STATES IN THE 1-GeV/c TO 3-GeV/c REGION

Lesikar, James Daniel, II ;
UMI-82-16334, 1981.
Inspire Record 173471 DOI 10.17182/hepdata.37232

None

1 data table
Table 1

No description provided.


First Measurement of the Photon Structure Function F2

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 107 (1981) 168-172, 1981.
Inspire Record 167681 DOI 10.17182/hepdata.31043

Using data taken at PETRA we present results on deep inelastic electron photon scattering at momentum transfers 1 < Q 2 < 15 GeV 2 . The results are expressed in terms of the photon structure function F 2 and are compared with QCD predictions and “hadronic” models of the photon. The pointlike component of the photon is found to be dominant.

2 data tables
Table 1

Data read from graph.. Data for W < 3.5 in Berger et al. 1981, PL 99B,287 (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+1164> RED = 1164 </a>).

Table 2

PHOTON STRUCTURE FUNCTION. NUMERICAL VALUES OF DATA ON FIGURE SUPPLIED BY W. WAGNER.


Energy Dependence of Jet Measures in $e^+ e^-$ Annihilation

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Z.Phys.C 12 (1982) 297, 1982.
Inspire Record 169193 DOI 10.17182/hepdata.16424

The jet character of the hadronic final states produced ine+e− annihilations is studied in terms of jet measures such as thrust, sphericity, jet opening angle and jet masses, in the energy range 7.7 to 31.6 GeV. All distributions and averages have been corrected for detector effects and initial state radiation. The energy dependence of the averages of these jet quantities is used to estimate the contributions due to perturbative QCD and fragmentation effects. Correlations between the jet measures and the multiplicity of charged hadrons are also presented.

12 data tables
Table 1

DIFFERENTIAL THRUST DISTRIBUTIONS WHERE THRUST IS MAX(SUM(ABS(PLONG))/SUM(ABS(P))).

Table 2

MEAN THRUST VALUES AS A FUNCTION OF CM ENERGY.

Table 3

DIFFERENTIAL SPERICITY DISTRIBUTIONS WHERE SPHERICITY IS 3/2*MIN(SUM(PT**2)/SUM(ABS(P))).

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MEASUREMENTS OF THE MULTIPLICITIES IN THE COLLISION OF HADRONS WITH HEAVY NUCLEI AT 200-GEV/C

Brick, D.H. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Nucl.Phys.B 201 (1982) 189-196, 1982.
Inspire Record 181081 DOI 10.17182/hepdata.34199

We report on the interactions of an incident 200 GeV / c beam composed of 33% protons, 16% kaons, and 48% pions on targets of silver and gold mounted in the Fermilab 30″ bubble chamber. Within our limited statistics, we find the total cross sections and average multiplicities to agree with previously published data. We find the KNO scaling distribution curve to be broader for heavy nuclei than for hydrogen. We present the first data for V 0 production on gold and silver. We also present, for the first time, evidence for a positive charge excess among the sample of relativistic tracks from interactions on gold and silver. We observe a trend where the positive charge excess increases with target atomic number and with increasing charged particle multiplicity. We find the charge excess to exist among the sample of particles having greater than 2 GeV / c momentum and to persist in the sample with momentum greater than 4 GeV / c .

4 data tables
Table 1

SIG REFERS PRODUCTION OF 2 OR MORE CHARGED PARTICLES EXCLUDING ELASTICS BUT INCLUDING COHERENT PRODUCTION. MULT REFERS TO RELATIVISTIC SECONDARIES (BETA > 0.7).

Table 2

NO CORRECTION FOR GAMMA CONVERSIONS IN THE TARGET IN THIS TABLE BUT DIFFERENCE DOES NOT NEED CORRECTION.

Table 3

No description provided.

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A Study of Two Photon Production of Two-body Final States With Invariant Mass Greater Than 2.0-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Nucl.Phys.B 202 (1982) 189-200, 1982.
Inspire Record 176691 DOI 10.17182/hepdata.34157

We have measured the electron, muon, and charged-hadron pair production rates in two-phonon interactions for invariant masses above 2.0 GeV over a large of momentum transfer. The cross sections for electron and muon pairs show good agreement with the QED predictions at both small and large momentum transfer. The observed rate of hadron production is less than 6% of the rate that QED predicts for point-like hadrons, consistent with recent leading-order QCD calculations.

5 data tables
Table 1

LOW Q**2 CROSS SECTIONS.

Table 2

DIFFERENTIAL CROSS SECTIONS IN THE INVARIANT MASS FOR MUON AND ELECTRON PAIRS IN THE UNTAGGED, LOW Q**2 REGION.

Table 3

HIGH Q**2 CROSS SECTIONS.

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Inclusive Strange Resonance Production in $p p$, $\pi^+ p$ and $K^+ p$ Interactions at 147 GeV/c

Brick, D. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Phys.Rev.D 25 (1982) 2248-2258, 1982.
Inspire Record 176545 DOI 10.17182/hepdata.23976

We have studied the inclusive production of K*±(890) and Y*±(1385) in pp, π+p, and K+p interactions at 147 GeV/c. The experiment used the Fermilab 30-inch hydrogen bubble chamber with the hybrid spectrometer system. Results are based on a sample of 1916 observed KS and 932 observed A. Inclusive cross sections are given for K*± and Y*± production from the three beams, and comparisons are made with experiments at other energies. Feynman-x and transverse-momentum-squared distributions are also calculated. The results suggest that the K*− is entirely produced in the central region, while the K*+ includes a component from beam fragmentation. Comparisons are made with the additive quark model.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Topological, Total and Elastic Cross-sections for $K^+ p$, $\pi^+ p$ and $p p$ Interactions at 147-{GeV}/$c$

Brick, D. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Phys.Rev.D 25 (1982) 2794, 1982.
Inspire Record 11840 DOI 10.17182/hepdata.4111

The Fermilab hybrid 30-in. bubble-chamber spectrometer was exposed to a tagged 147-GeV/c positive beam containing π+, K+, and p. A sample of 3003 K+p, 19410 pp, and 20745 π+p interactions is used to derive σn, 〈n〉, f2cc, and 〈nc〉D for each beam particle. These values are compared to values obtained at other, mostly lower, beam momenta. The overall dependence of 〈n〉 on Ea, the available center-of-mass energy, for these three reactions as well as π−p and pp interactions has been determined.

13 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 R in $e^+ e^-$ Annihilation for $\sqrt{s}$ Between 7.4-{GeV} and 9.4-{GeV}

The LENA collaboration Niczyporuk, B. ; Jakubowski, Z. ; Nowak, G. ; et al.
Z.Phys.C 15 (1982) 299, 1982.
Inspire Record 179431 DOI 10.17182/hepdata.16412

The rationR=σ(e+e−→hadrons)/σ(e+e−→ µ+ µ−) was measured with the LENA detector at DORIS in a scan between 7.40 and 7.48 GeV and between 8.67 and 9.43 GeV center of mass energies. Corrected for QED radiative effects,R is found to be constant with an average value ofR=3.37 ±0.06stat±0.23syst. No narrow resonances withΓee(Γhad/Γtot)⊗0.30 keV (95% C.L.) and no steps have been observed. Based on this value ofR, revised values for υ(1S) resonance parameters are presented.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

NUMERICAL VALUES GIVEN IN APPENDIX IN PREPRINT. STATISTICAL ERRORS ONLY.