Johnson, P.
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Measurement of $\pi^{\pm}$p Backward Elastic Scattering Between 30 and 90 GeV/c

Baker, W.F. ; Eartly, David P. ; Kalbach, R.M. ; et al.
Phys.Rev.Lett. 43 (1979) 1635, 1979.
Inspire Record 141766 DOI 10.17182/hepdata.20758

Measurements of π±p backward elastic scattering have been made for incident pion momenta between 30 and 90 GeV/c and for 0<−u<0.5 (GeV/c)2. The momentum dependence of the cross sections is of a form expected from a simple Regge model, and the u dependence of the cross sections is similar to that observed at lower momenta.

9 data tables
Table 1

No description provided.

Table 2

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Table 3

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Evidence for Planar Events in e+ e- Annihilation at High-Energies

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 86 (1979) 243-249, 1979.
Inspire Record 142123 DOI 10.17182/hepdata.27312

Hadron jets produced in e + e − annihilation between 13 GeV and 31.6 GeV in c.m. at PETRA are analyzed. The transverse momentum of the jets is found to increase strongly with c.m. energy. The broadening of the jets is not uniform in azimuthal angle around the quark direction but tends to yield planar events with large and growing transverse momenta in the plane and smaller transverse momenta normal to the plane. The simple q q collinear jet picture is ruled out. The observation of planar events shows that there are three basic particles in the final state. Indeed, several events with three well-separated jets of hadrons are observed at the highest energies. This occurs naturally when the outgoing quark radiates a hard noncollinear gluon, i.e., e + e − → q q g with the quarks and the gluons fragmenting into hadrons with limited transverse momenta.

1 data table
Table 1

NORMALIZED TRANSVERSE MOMENTUM DISTRIBUTION WITH RESPECT TO THE SPHERICITY AXIS AT 13, 17, AND 27.4 TO 31.6 GEV.


First Evidence for $\Upsilon$ Production by Pions

The Saclay-CERN-College de France-Ecole Poly-Orsay collaboration Badier, J. ; Boucrot, J. ; Burgun, G. ; et al.
Phys.Lett.B 86 (1979) 98-102, 1979.
Inspire Record 142739 DOI 10.17182/hepdata.27309

We have measured the production of massive muon pairs in hadronic collisions at the CERN Super Proton Synchrotron (SPS). A clear signal of production of the ϒ resonance by π + of 200 GeV/ c and π − of 200 and 280 GeV/ c on a platinum target is observed.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


The hadronic final state in $e^{+}e^{-}$ annihilation at c.m. energies of 13, 17 and 27.4 GeV

The TASSO collaboration Cashmore, R.J. ; Brandelik, R. ; Braunschweig, W. ; et al.
1 (1979) 330-337, 1979.
Inspire Record 142275 DOI 10.17182/hepdata.45234

Results on the hadronic final state in e/sup +/e/sup -/ annihilation at 13, 17 and 27.4 GeV are presented. There is no compelling evidence for the existence of the t quark in these data, which are in general agreement with a simple quark parton model. Some tentative indications of QCD effects are observed in the p/sub T//sup 2/ distributions.

2 data tables
Table 1

TAU HEAVY LEPTON CONTRIBUTION SUBTRACTED.

Table 2

INCLUSIVE HADRON SPECTRUM. THESE DATA AT 13, 17 AND 27.4 GEV ON S*D(SIG)/DX ARE INCLUDED IN THE RECORD OF R. BRANDELIK ET AL., PL 89B, 418 (1980).


X Dependence of the Proton Structure Functions From Inelastic Anti-neutrino - Proton Scattering

Fernandez, E. ; Barnes, V.E. ; Carman, T.S. ; et al.
Phys.Rev.Lett. 43 (1979) 1975, 1979.
Inspire Record 8235 DOI 10.17182/hepdata.20741

From an analysis of 2275 ν¯p→μ++X0 events at an average Q2 of 4.5 GeV2, there are presented the first measurements, up to one undetermined overall normalization constant, of the x dependence of the proton structure functions using antineutrinos, and of the u and d¯+s¯ quark distributions. The result for u(x) is in good agreement with models based on fits to electron and muon scattering data. With u(x) normalized to those models the absolute antiquark momentum distribution x[d¯x+s¯(x)] in the proton is determined.

1 data table
Table 1

No description provided.


Discovery of Three Jet Events and a Test of Quantum Chromodynamics at PETRA Energies

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 43 (1979) 830, 1979.
Inspire Record 142085 DOI 10.17182/hepdata.20742

We report the analysis of the spatial energy distribution of data for e+e−→hadrons obtained with the MARK-J detector at PETRA. We define the quantity "oblateness" to describe the flat shape of the energy configuration and the three-jet structure which is unambiguously observed for the first time. Our data can be explained by quantum chromodynamic predictions for the production of quark-antiquark pairs accompanied by hard noncollinear gluons.

1 data table
Table 1

AVERAGE OBLATENESS AS A FUNCTION OF SQRT(S) AND OF THRUST AND OBLATENESS DISTRIBUTION (1/N)*DN/DOBLATENESS AT 17 AND 27.4 TO 31.6 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.


Production of High Mass Muon Pairs in $\pi^-$ Be Collisions at 150-{GeV}/$c$ and 175-{GeV}/$c$

Barate, R. ; Bareyre, P. ; Bonamy, P. ; et al.
Phys.Rev.Lett. 43 (1979) 1541, 1979.
Inspire Record 142156 DOI 10.17182/hepdata.20768

This paper presents production and decay characteristics of 500 high-mass, high-resolution μ+μ− pairs produced in π− Be collisions at 150 and 175 GeV/c. The data do not agree with a simple Drell-Yan production mechanism, but indicate that higher-order quantum-chromodynamic corrections must be included.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


A Test of Universality of Charged Leptons

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 43 (1979) 1915, 1979.
Inspire Record 142012 DOI 10.17182/hepdata.20759

Measurements of the reactions e++e−→e++e−, μ++μ−, and τ++τ− at PETRA energies (s12=13,17,27.4,30 and 31.6 GeV) are reported. The results show that these reactions agree well with the predictions of quantum electrodynamics thus determining that all the known charged leptons are pointlike particles to a distance < × 10−16 cm.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Experimental Proof of the Existence of the A1 Meson

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.
Phys.Lett.B 89 (1980) 281-284, 1980.
Inspire Record 143044 DOI 10.17182/hepdata.27272

In partial wave analyses of the ( π − π − π + ) system, substantial shape changes of the 1 + S ( ϱπ ) intensity as a function of t , and relative phase changes of ≈ 90°, provide compelling evidence for a resonant A 1 of mass ≈ 1280 MeV and width ≈ 300 MeV.

1 data table
Table 1

No description provided.


3 $\pi$ Resonances in 2- Partial Waves

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.
Phys.Lett.B 89 (1980) 285-289, 1980.
Inspire Record 143045 DOI 10.17182/hepdata.27275

The J PC = 2 −+ partial wave intensities and their large phase changes prove the resonant nature of the A 3 meson (mass ≈ 1670 MeV, width ≈ 210 MeV). The decay modes are f 0 π , ϱ 0 π , and ϵ 0 π . Evidence is found for a further 2 − enhancement.

1 data table
Table 1

No description provided.