Chang, Tseng-Hsu
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rivet Analysis
Study of Electron - Positron Collisions at the Highest {PETRA} Energy

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Lett.B 85 (1979) 463-466, 1979.
Inspire Record 141976 DOI 10.17182/hepdata.27332

We report on the results of the study of e + e − collisions at the highest PETRA energy of √ s = 31.57 GeV, using the 4π sr, electromagnetic and calorimetric detector Mark J. Based on 88 hadron events, and an integrated luminosity of 243 nb −1 we obtain R = σ (e + e − → hadrons)/ σ (e + e − → μ + μ − ) = 4.0 ± 0.5 (statistical) ± 6 (systematic). The R value, the measured thrust distribution and average spherocity show no evidence for the production of new quark flavors.

2 data tables
Table 1

CORRECTIONS FOR TWO-PHOTON PROCESSES, TAU HEAVY LEPTON PRODUCTION AND INITIAL STATE RADIATIVE CORRECTIONS HAVE BEEN APPLIED.

Table 2

THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 31.57 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.


Study of Electron - Positron Collisions at the Center-of-mass Energies of 27.4-{GeV} and 27.7-{GeV} at {PETRA}

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 43 (1979) 901, 1979.
Inspire Record 141542 DOI 10.17182/hepdata.20739

This paper reports on the first results of the study of e+e− collisions at s=27.4 GeV and s=27.7 GeV at PETRA, using the 4π-sr electromagnetic and calorimetric detector MARK-J. We obtain an average R=σ(e+e−→hadrons)σ(e+e−→μ+μ−)=3.8±0.3 (statistical)±0.6 (systematic) and a relative R=1.0±0.2 between the two energies. The R values, the measured thrust distribution, and average spherocity show no evidence for the production of new quark flavors.

2 data tables
Table 1

THE RELATIVE VALUE OF R BETWEEN THESE TWO ENERGIES IS 1.0 +- 0.2.

Table 2

THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 13, 17 AND 27 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.


Test of Quantum Electrodynamics at {PETRA} Energies

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 42 (1979) 1110, 1979.
Inspire Record 140093 DOI 10.17182/hepdata.20817

We report on the measurement of the reaction e+e−→e+e− with a large—solid-angle electromagnetic shower detector at center-of-mass energies s=13 and 17 GeV. Comparison of our results with predictions of quantum electrodynamics shows excellent agreement in both the angular distribution and energy dependence. Values of cutoff parameters are also given.

1 data table
Table 1

No description provided.


rivet Analysis
Cross-Sections and Event Topologies in e+ e- Annihilation at 13-GeV and 17-GeV Observed with the PLUTO Detector

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 81 (1979) 410-415, 1979.
Inspire Record 140294 DOI 10.17182/hepdata.45239

First results from the magnetic detector PLUTO at the new e + e − storage ring PETRA are shown. The ratio R of the cross section for hadron production to that for μ-pair production has been measured to be R = 5.0 ± 0.5 at 13 GeV and 4.3 ±0.5 at 17 GeV. Both values have an additional systematic error of 20%. The events show a typical 2-jet structure. The mean transverse momentum approaches a constant value with increasing energy implying a shrinkage of the jet opening angle.

2 data tables
Table 1

TAU HEAVY LEPTON PAIR CONTRIBUTIONS HAVE BEEN SUBTRACTED. R AT 13 AND 17 GEV, TOGETHER WITH SOME SELECTED LOWER ENERGY MEASUREMENTS FROM PLUTO AT DORIS.

Table 2

Data from earlier preprint DESY-79-06. NUMERICAL VALUES MEASURED OFF GRAPH IN PREPRINT.


INCLUSIVE PRODUCTION OF K*+- (890) AND SIGMA+- (1385) RESONANCES IN ANTI-P P INTERACTIONS AT 14.75-GEV/C

Canter, J. ; Chang, C.C ; Dao, F.T. ; et al.
Phys.Rev.D 20 (1979) 1029-1036, 1979.
Inspire Record 144992 DOI 10.17182/hepdata.24210

The inclusive and semi-inclusive cross sections for K*±(890) and Σ±(1385) resonances are determined in p¯p interactions at 14.75 GeV/c. They account for a large fraction of the KS0 and Λ0 produced. The K*-resonance production also affects the low-pT2 distribution of inclusive KS0. The x distributions of the resonance production are studied in terms of a simple quark-recombination model.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of the Relative Total Hadronic Cross-section R at {PETRA}

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D. ; Becker, U. ; Boehm, A. ; et al.
Phys.Rev.Lett. 42 (1979) 1113, 1979.
Inspire Record 140059 DOI 10.17182/hepdata.3235

We report the first measurement of the ratio R=(σe+e−→hadrons)(σe+e−→μ+μ−) (with negligible τ-lepton contribution) at a center-of-mass energy s=13 GeV and s=17 GeV, from the just finished electron-positron colliding-beam facility PETRA. The detector, MARK-J, has an approximately 4π solid angle and measures γ, e, μ, and charged and neutral hadrons simultaneously. Our results yield R(s=17 GeV)=4.9±0.6 (statistical) ±0.7 (systematic error), and R(s=13 GeV)=4.6±0.5 (statistical) ±0.7 (systematic error). The ratio R(s=17 GeV)R(s=13 GeV) is 1.08±0.18.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Results from pluto at petra

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
1 (1979) 343-349, 1979.
Inspire Record 148976 DOI 10.17182/hepdata.45229

None

1 data table
Table 1

No description provided.


A Search for Longlived Neutral Heavy Leptons in 400 GeV/c Proton Interactions

Bechis, D.J. ; Chang, C.Y. ; Dombeck, T.W. ; et al.
Phys.Rev.Lett. 40 (1978) 602-604, 1978.
Inspire Record 6478 DOI 10.17182/hepdata.37888

We report a null search for neutral heavy leptons produced unaccompanied by muons in 400-GeV/c proton-nucleon collisions in a magnetized beam dump and decaying in vacuum downstream. The upper limit on σB for L0's with Feynman x≳0.2 and θlab≲10 mrad with branching ratio B into two charged particles is σB≲2.8×10−35 cm2/nucleon at the 90% confidence level for masses below 1.0 GeV/c2 and lifetimes between 10−10 and 10−8 sec.

1 data table
Table 1

No description provided.


Production of High Momentum Mesons at Small Angles at a Center-of-mass Energy of 45-{GeV} at the {CERN} {ISR}

The CHLM collaboration Singh, J. ; Albrow, M.G. ; Barber, D.P. ; et al.
Nucl.Phys.B 140 (1978) 189-219, 1978.
Inspire Record 130229 DOI 10.17182/hepdata.55051

Inclusive cross sections for the production of π ± and K ± mesons in proton-proton collisions have been measured at a c.m. energy √ s = 45 GeV, in the range 0.41 < x < 0.95 and 0.35 < p T < 1.45 GeV, where x = 2 p L/√ s and p L , p T are the longitudinal and transverse components of the momentum of the meson. Within the measured range the p T dependence of the invariant cross section is essentially independent of x and weakly dependent on the type of particle. For all particles the invariant cross sections at fixed p T fall by three orders of magnitude between x = 0.4 and 0.95. Except at the highest values of x and p T , the statistical accuracy is better than 10%. The data are compared with a triple-Regge model and with a simple quark-parton model.

78 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Search for xi* Production in K- p Interactions at 2.87-GeV/c

Briefel, E. ; Gourevitch, S.A. ; Kirsch, L. ; et al.
Phys.Rev.D 16 (1977) 2706, 1977.
Inspire Record 118843 DOI 10.17182/hepdata.24494

Evidence is presented for production of Ξ* resonances, decaying into Ξπ, Ξ(1530)π, ΛK¯, and ΣK¯, in K−p interactions at 2.87 Gev/c. The data represent final combined results from a 30-events/μb hydrogen exposure and an 18-events/μb exposure in deuterium designed to study Ξ* production in the mass interval 1.46-2.07 GeV/c2. In addition to Ξ(1820) and Ξ(1940), signals have been observed at masses of 1630 MeV/c2 and 1860 MeV/c2 decaying into Ξ−π+ and YK¯, respectively. Reaction cross sections have been measured for all final states containing two visible signs of strangeness, and for the final states ΛK−K+ and Σ0K−K+.

4 data tables
Table 1

CROSS SECTIONS ARISING FROM VARIOUS TOPOLOGIES.

Table 2

K- P CROSS SECTIONS FROM DEUTERIUM TARGET EXPERIMENT. RESULTS ARE IN GOOD AGREEMENT WITH THE HYDROGEN DATA.

Table 3

No description provided.

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