Jahnen, T.
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Search for Narrow Resonances in $e^+ e^-$ Annihilation at c.m. Energies Between 29.90-{GeV} and 31.46-{GeV}

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 91 (1980) 152-154, 1980.
Inspire Record 152290 DOI 10.17182/hepdata.27258

A search for narrow resonances in e + e − annihilation at c.m. energies between 29.90 and 31.46 GeV provides no evidence for the existence of such states. The 90% confidence upper limit on the integrated resonance cross section is 38 nb MeV, significantly below the value expected for the lowest (t,t̄) bound state.

1 data table
Table 1

No description provided.


rivet Analysis
PHYSICS WITH HIGH-ENERGY ELECTRON POSITRON COLLIDING BEAMS WITH THE MARK-J DETECTOR

The MARK-J & AACHEN-DESY-MIT-NIKHEF-BEIJING collaborations Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rept. 63 (1980) 337-391, 1980.
Inspire Record 158857 DOI 10.17182/hepdata.27618

This report reviews the experimental investigation of high energy e + e − interactions by the MARK J collaboration at PETRA, the electron-positron colliding beam accelerator at DESY in Hamburg, Germany. The physics objectives include studies of several purely electromagnetic processes and hadronic final states, which further our knowledge of the nature of the fundamental constituents and of their strong, electromagnetic and weak interactions. Before discussing the physics results, the main features and the principal components of the MARK J detector are discussed in terms of design, function, and performance. Several aspects of the on-line data collection and the off-line analysis are also outlined. Results are presented on tests of quantum electrodynamics using e + e − → e + e − , μ + μ − and τ + τ − , on the measurement of R , the ratio of the hadronic to the point-like muon pair cross section, on the search for new quark flavors, on the discovery of three jet events arising from the radiation of hard noncollinear gluons as predicted by quantum chromodynamics, and on the determination of the strong coupling constant α s .

4 data tables
Table 1

SUMMARY OF RESULTS FOR R FROM TOTAL OF 2595 HADRON EVENTS. INCLUDES RED = 1046, 1079, 1072 AND 1114.

Table 2

MEAN THRUST AND THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 13, 17, 22 AND 30 GEV. SOMEWHAT DETECTOR DEPENDENT. INCLUDES RED = 1079 AND 1072. SEE ALSO RED = 1114. ALSO JET ANALYSIS USING FOX-WOLFRAM MOMENTS.

Table 3

OBLATENESS DISTRIBUTION AT 17 AND 27.4 TO 31.6 GEV. SEE RED = 1146.

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INCLUSIVE AND SEMIINCLUSIVE PRODUCTION OF POSITIVE PIONS AND PROTONS IN ANTI-P P INTERACTIONS AT 22.4-GEV/C

The ALMA ATA-DUBNA-HELSINKI-MOSCOW-PRAGUE-TBILISI collaboration Boos, E.G. ; Ermilova, D.I. ; Samoilov, V.V. ; et al.
Nucl.Phys.B 174 (1980) 45-67, 1980.
Inspire Record 159212 DOI 10.17182/hepdata.7929

New results on the inclusive and semi-inclusive production of π + mesons and protons in the whole phase space are given for about 2.2 · 10 4 inelastic p p interactions at 22.4 GeV/ c . A method of statistical separation for spectra of particles of the same charge which are produced in CP -symmetrical reactions is discussed in detail. Experimental data are compared with quark-parton model predictions.

3 data tables
Table 1

No description provided.

Table 2

NON-ANNIHILATION EVENTS ONLY.

Table 3

No description provided.


Two Particle Correlations Between Secondary Protons Arising From $\pi^- c^-$12 Interactions at 40-{GeV}/c

Angelov, N. ; Akhababian, N. ; Balea, O. ; et al.
Sov.J.Nucl.Phys. 32 (1980) 700, 1980.
Inspire Record 152653 DOI 10.17182/hepdata.18014

None

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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MEASUREMENT OF THE AVERAGE ENERGY OF CHARGED PARTICLES IN C.M.S FOR THE ANTI-P P INTERACTIONS AT 22.4-GEV/C.

The ALMA ATA-DUBNA-MOSCOW-PRAGUE-TBILISI-HELSINKI collaboration Boos, E.G. ; Ermilova, D.I. ; Samoilov, V.V. ; et al.
Yad.Fiz. 31 (1980) 947-955, 1980.
Inspire Record 157619 DOI 10.17182/hepdata.18035

None

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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EVIDENCE AGAINST THE NARROW S (1936) IN A MEASUREMENT OF ANTI-P P TOTAL CROSS-SECTION

Kamae, T. ; Aihara, H. ; Chiba, J. ; et al.
Phys.Rev.Lett. 44 (1980) 1439-1442, 1980.
Inspire Record 157934 DOI 10.17182/hepdata.20724

The total p¯p cross section has been measured in the S region by the transmission method with use of a beam-monitoring spectrometer. The result is inconsistent with the existence of the narrow resonance S(1936) with cross sections reported by previous experiments.

1 data table
Table 1

No description provided.


EXPERIMENTAL STUDY OF HEAVY CHARGED LEPTONS AT PETRA

Barber, D.P. ; Becker, U. ; Bei, G.D. ; et al.
Phys.Rev.Lett. 45 (1980) 1904-1907, 1980.
Inspire Record 158858 DOI 10.17182/hepdata.20675

Data from the MARK-J detector on the reactions e+e−→μ+μ−, τ+τ− in the center-of-mass energy range from 12 to 36.7 GeV are presented. The μ, τ radii are shown to be <10−16 cm. A search has been made for the production of a new heavy lepton and for the production of spin-0 supersymmetric partners of the muon. 95%-confidence-level lower limits of 16 GeV for the mass of a new charged heavy lepton and 15 GeV for the mass of the scalar partners of the muon are obtained.

1 data table
Table 1

No description provided.


Observation of Upsilon, Upsilon', and Upsilon'' at the Cornell electron Storage Ring

Bohringer, T. ; Costantini, F. ; Dobbins, J. ; et al.
Phys.Rev.Lett. 44 (1980) 1111-1114, 1980.
Inspire Record 157729 DOI 10.17182/hepdata.20731

The ϒ, ϒ′, and ϒ′′ states have been observed at the Cornell Electron Storage Ring as narrow peaks in σ(e+e−→hadrons) versus beam energy. Data were collected during a run with integrated luminosity of 1000 nb−1, using the Columbia University-Stony Brook segmented NaI detector. The measured mass differences are M(ϒ′)−M(ϒ)=559±1(±3) MeV and M(ϒ′′)−M(ϒ)=889±1(±5) MeV, where the errors in parentheses represent systematic uncertainties. Preliminary values for the leptonic width ratios were also obtained.

1 data table
Table 1

HADRONIC EVENTS/SMALL-ANGLE BHABHA YIELD.


INCLUSIVE K0, LAMBDA0, K*+- (890), AND SIGMA*+- (1385) PRODUCTION IN P P COLLISIONS AT 300-GEV/C

Lopinto, F. ; Brody, A. ; Engelmann, R. ; et al.
Phys.Rev.D 22 (1980) 573-581, 1980.
Inspire Record 158990 DOI 10.17182/hepdata.24150

Inclusive K0K¯0, Λ0, and Λ¯0 cross sections have been determined using a 292-event/mb exposure of the hydrogen-filled 15-foot bubble chamber at Fermilab. From the invariant-mass distributions of V0π± pairs we find that σ(K*±(890))=4.4±1.4 mb, σ(Σ*±(1385))=0.54±0.40 mb, and σ(Σ¯*±(1385))=0.45±0.34 mb. It is estimated that 0.32 ± 0.11 of K0K¯0's, 0.21 ± 0.16 of Λ's, and 0.96 ± 0.75 of Λ¯'s originate from decays of K*(890) and Σ*(1385), respectively.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


TOTAL AND PARTIAL ANTI-P D CROSS-SECTIONS FROM 0.26-GEV/C TO 0.47-GEV/C

Kalogeropoulos, T. ; Tzanakos, G.S. ;
Phys.Rev.D 22 (1980) 2585-2594, 1980.
Inspire Record 160438 DOI 10.17182/hepdata.24164

The p¯d total cross section is ∼10% larger than the A+BP extrapolated cross section seen at higher (∼0.5-2.0 GeV/c) momenta. The excess is mainly due to the nonannihilation part of the total cross section. The p¯d annihilation cross sections in H2 and D2 are the same. These observations are consistent with known properties of the N¯N(1897). A 3σ dip is present at ∼0.43 GeV/c mainly due to pp¯ annihilation. This dip cannot be understood in terms of a single resonance at N¯N(1897) and the S(1935). Our cross sections are ∼10-20% higher than the recent measurements of Hamilton et al.

1 data table
Table 1

No description provided.