De Clercq, C.
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Measurement of Dimuon Production at the {ISR}

Antreasyan, D. ; Atwood, W. ; Battiston, R. ; et al.
Phys.Rev.Lett. 45 (1980) 863, 1980.
Inspire Record 153857 DOI 10.17182/hepdata.20656

Prompt dimuon production has been measured. Events with mass up to 25 GeV/c2 are observed, as well as the J and ϒ resonances. Cross sections are given for J and ϒ production. For the continuum, the scaling function F(τ) is measured at very small values of τ=ms covering the range 0.05<τ<0.20.

3 data tables
Table 1

No description provided.

Table 2

HERE UPSILON = ALL USILON FAMILY. ANGULAR DISTBN. IS SEEN TO BE ISOTROPIC.

Table 3

No description provided.


Measurement of the Reaction $e^+ e^- \to \gamma \gamma$ at {CMS} Energies From 9.4-{GeV} to 31.6-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 94 (1980) 87-90, 1980.
Inspire Record 153120 DOI 10.17182/hepdata.27174

The differential cross section for the reaction e + e − → γγ has been measured in the CMS energy range between 9.4 and 31.6 GeV. The results are found to be in agreement with the predictions of quantum electrodynamics up to momentum transfers- q 2 of 900 GeV 2 . The data set lower limits of about 40 GeV on QED cut-off parameters. We have searched for the decay υ (9.46) → γγ and obtain an upper limit Γ ( υ → γγ )/ Γ ( υ → all) < 1.4% (95% c.l.).

1 data table
Table 1

No description provided.


Observation of a Fourth Upsilon State in e+ e- Annihilations

The CLEO collaboration Andrews, D. ; Berkelman, Karl ; Cabenda, R. ; et al.
Phys.Rev.Lett. 45 (1980) 219, 1980.
Inspire Record 153182 DOI 10.17182/hepdata.20674

A fourth state in the upsilon energy region has been seen in e+e− collisions at the Cornell Electron Storage Ring. A resonance is observed with a mass 1112±5 MeV above the lowest upsilon state. The 9.6-MeV rms width is greater than the 4.6-MeV energy resolution of the e+e− beams. The observed characteristics of the new state make it a likely candidate for the 4S3 state of the bb¯ system, lying above the threshold for the production of B mesons.

1 data table
Table 1

NOT CORRECTED FOR TAU HEAVY LEPTON PRODUCTION NOR TWO-PHOTON COLLISIONS.


Test of {QED} in $e^+ e^-$ Annihilation at Energies Between 12-{GeV} and 31.6-{GeV}

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 94 (1980) 259-265, 1980.
Inspire Record 153127 DOI 10.17182/hepdata.45228

We have measured the reactions e + e − → e + e − → μ + μ − and e + e − → γγ at c.m. energies between 12 and 31.6 GeV. Excellent agreement with the predictions of QED has been found, resulting in cut off parameters Λ + > 112 GeV and Λ − > 139 GeV for the first process and Λ + > 34 GeV and Λ − > 42 GeV (95% c.1.) for the last one. A limit on the Weinberg angle of sin 2 θ W < 0.55 (95% c.1.) has been obtained.

3 data tables
Table 1

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.

Table 2

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.

Table 3

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.


Photoproduction of $K^+ K^-$ Pairs on Hydrogen at Photon Energies of 20-{GeV} to 36-{GeV}

The Bonn-CERN-Ecole Poly-Glasgow-Lancaster-Manchester-Orsay-Paris-Rutherford-Sheffield collaboration Aston, D. ; Atkinson, M. ; Bailey, R. ; et al.
Nucl.Phys.B 172 (1980) 1-12, 1980.
Inspire Record 153022 DOI 10.17182/hepdata.34516

The reaction γ p→K + K − p has been investigated with photons in the energy range of 20< E γ <36 GeV and with K + K − pairs in the mass range of M K + K − <2.0 GeV. The production of the φ(1019) contributes with a cross section σ ( γ p → φ p) × BR( φ →K + K − ) = 240±6 nb with an additional systematic error of ±20 nb. In the higher mass range of 1.05< M K + K − <2.0 GeV the production of K + K − pairs yields a cross section σ ( γ p→K + K − p) = 160±8 nb with an additional systematic error of +40 −30 nb.

3 data tables
Table 1

No description provided.

Table 2

K+ K- PRODUCTION ABOVE PHI MASS.

Table 3

No description provided.


General Features of the Anti-p $p$ Interaction at 12-{GeV}/c

Johnson, P. ; Mason, P. ; Muirhead, H. ; et al.
Nucl.Phys.B 173 (1980) 77-92, 1980.
Inspire Record 8886 DOI 10.17182/hepdata.34472

Simple inclusive cross sections for p p interactions at 12 GeV/ c are given. The data cover prong cross sections, V 0 production and resonances. Separation has been made into annihilation and non-annihilation modes. Some implications of the data are discussed. It is pointed out that the ratios of cross sections for ϱ 0 π − production are independent of incident antiproton momentum in p p annihilation processes, and that data at the highest available pp energies (ISR) tend to the same value.

1 data table
Table 1

NORMALIZED TO A TOTAL CROSS SECTION OF 51.7 +- 0.8 MB.


rivet Analysis
Total Cross-section for Hadron Production by Electron - Positron Annihilation at Adone

Ambrosio, M. ; Paternoster, G. ; Tortora, L. ; et al.
Phys.Lett.B 91 (1980) 155-160, 1980.
Inspire Record 152630 DOI 10.17182/hepdata.27239

The total cross section for electron-positron annihilation into three or more hadrons has been measured for centre of mass energies between 1.4 and 2.0 GeV. The data were obtained at ADONE by the BB̄ experiment.

1 data table
Table 1

NOTE THAT THIS MEASUREMENT OF R EXCLUDES TWO-BODY FINAL STATE EVENTS. RADIATIVE CORRECTIONS WERE APPLIED.


Observation of Three Upsilon States

The CLEO collaboration Andrews, D. ; Berkelman, Karl ; Billing, M. ; et al.
Phys.Rev.Lett. 44 (1980) 1108, 1980.
Inspire Record 152393 DOI 10.17182/hepdata.20733

Three narrow resonances have been observed in e+e− annihilation into hadrons at total energies between 9.4 and 10.4 GeV. Measurements of mass spacing and ratios of lepton pair widths support the interpretation of these "ϒ" states as the lowest triplet-S levels of the bb¯ quark-antiquark system.

1 data table
Table 1

No description provided.


The Relative Production of $\pi^+$, $K^+$, $p$ and $\overline{p}$ at Large Transverse Momentum in 200-{GeV} and 300-{GeV} $\pi^- -p$ Collisions

Frisch, Henry J. ; Giokaris, N.D. ; Green, J.M. ; et al.
Phys.Rev.Lett. 44 (1980) 511, 1980.
Inspire Record 8853 DOI 10.17182/hepdata.23865

This Letter reports measurements of the ratios of $\pi$, K, and p production at large values of transverse momentum in $\pi^- −p$ collisions. The charge ratios, such as $\frac {\pi^−} {\pi^+}$, $\frac {K^−} {K^+}$, and $\frac {\overline{p}}{p}$ are seen to be quite different from those measured in p −p collisions. These ratios are sensitive tests of hard-scattering models, and are compared with theoretical predictions. The particle ratios have also been studied as a function of center-of-mass angle ($\theta^*$) at $\theta^*$ = 90°, 77°, and 60°.

28 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive Production of $\rho^0$ and $\phi$ in $K^+ p$ Interactions at 32-{GeV}/c

The Soviet-CERN collaboration Vorobjev, A.P. ; Gerdyukov, L.N. ; Knyazev, V.V. ; et al.
Nucl.Phys.B 176 (1980) 303, 1980.
Inspire Record 153559 DOI 10.17182/hepdata.48999

Inclusive ϱ 0 and φ production is investigated in K + p interactions at 32 GeV/ c . Total and semi-inclusive ϱ 0 and φ cross sections, longitudinal and transverse momentum distributions, including 〈 P T versus x dependence are presented. No evidence for a sea-gull effect is observed. Comparison with quark models strongly suggests the possibility that a large fraction of the ϱ 0 and vector mesons are produced as fragmentation products of the incident particles. Study of uncorrelated π + π − pairs in the ϱ 0 mass range provides possible indirect evidence for the existence of diquarks in the proton.

39 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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