Yuan, Li
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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.


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.


COMPARISON OF DIRECT PHOTON PRODUCTION IN P P COLLISIONS AT S**(1/2) = 30.6-GEV AND 53.2-GEV

Amaldi, E. ; Beneventano, M. ; Borgia, B. ; et al.
Phys.Lett.B 84 (1979) 360-362, 1979.
Inspire Record 146580 DOI 10.17182/hepdata.27321

We present data obtained at the ISR, on the determination of the ratio R = γ π 0 at s = 30.6 GeV and we compare the results with our previous measurement at s = 53.2 GeV. The ratio R = γ π 0 integrated over the interval 0.1 ⩽ χ T ⩽ 0.2 is (1.6 ± 0.5) × 10 −2 and we obtain an indication of a universal χ T dependence.

1 data table
Table 1

No description provided.


INCLUSIVE ETA PRODUCTION IN P P COLLISION AT ISR ENERGIES

Amaldi, E. ; Beneventano, M. ; Borgia, B. ; et al.
Nucl.Phys.B 158 (1979) 1-10, 1979.
Inspire Record 145095 DOI 10.17182/hepdata.34663

We report on the experimental results obtained at the ISR for the η particle production at 90° and √ s = 30.6 and 53.2 GeV. We determine the invariant cross section and the p t distribution in the interval 1 ⩽ p t ⩽ 5 GeV/ c . We find that the p t distribution has the same shape of the π 0 production and differ from it by a constant factor R 90° = 0.5 ± 0.07.

1 data table
Table 1

No description provided.


SINGLE DIRECT PHOTON PRODUCTION IN P P COLLISIONS AT S**(1/2) = 53.2-GEV IN THE P(T) INTERVAL 2.3-GEV/C TO 5.7-GEV/C

Amaldi, E. ; Beneventano, M. ; Borgia, B. ; et al.
Nucl.Phys.B 150 (1979) 326-344, 1979.
Inspire Record 145596 DOI 10.17182/hepdata.34796

We report the results of an experiment made at the CERN ISR to investigate the possible diret production of single photons in pp collisions at √ s = 53.2 GeV at 90° and in the p t interval 2.3 to 5.7 GeV/ c . The value of the ratio R = n γ / n π 0 is compatible with zero for low p t ⪅ 3 GeV/ c but, in spite of the large error, shows a trend to increase for larger p t .

3 data tables
Table 1

THIS USES THE SO-CALLED D2L TRIGGER (SEE PAPER).

Table 2

THIS USES THE SO-CALLED D2MAX TRIGGER (SEE PAPER).

Table 3

THIS USES THE SO-CALLED D2MAX TRIGGER (SEE PAPER).


Total Cross-Sections of $\pi^{\pm}$, $K^{\pm}$, p and $\bar{p}$ on Protons and Deuterons Between 200 GeV/c and 370 GeV/c

Carroll, A.S. ; Chiang, I.H. ; Kycia, T.F. ; et al.
Phys.Lett.B 80 (1979) 423-427, 1979.
Inspire Record 132765 DOI 10.17182/hepdata.27362

Total cross sections of π ± , K ± , p and p on protons and deuterons have been measured at 6 momenta between 200 and 370 GeV/ c .

24 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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A Search for Six Quark States

Carroll, A.S. ; Chiang, I.-H. ; Johnson, R.A. ; et al.
Phys.Rev.Lett. 41 (1978) 777, 1978.
Inspire Record 131409 DOI 10.17182/hepdata.50368

We have searched the missing-mass spectrum of the reaction pp→K+K+X for a narrow six-quark resonance in the mass range 2.0-2.5 GeV/c2. No narrow structure was observed. Upper limits for the production cross section of such a state depend upon mass and vary from 30 to 130 nb.

1 data table
Table 1

No description provided.


Exclusive Vector Meson Production in Muon - Proton Scattering

del Papa, C. ; Dorfan, David E. ; Flatte, Stanley M. ; et al.
Phys.Rev.D 19 (1979) 1303, 1979.
Inspire Record 130570 DOI 10.17182/hepdata.24312

From a muon-proton scattering experiment with a streamer chamber at the Stanford Linear Accelerator we present results in the ranges 0.3<Q2<4.7 GeV2 and 1.7<W<4.7 GeV for the reactions μ+p→μpV where V is a vector meson (ρ0, ω, or φ). It is shown that in ρ production the skewing parameter and the longitudinal-transverse ratio change significantly as Q2 increases above 1 GeV2. The cross section for ρ0 production as a function of Q2 falls below the vector-meson-dominance prediction. The ratio of the cross section for exclusive vector-meson production to the total cross section falls by a factor of 10 between photoproduction and a Q2 of 2 GeV2, yet the ratio of ω to ρ production remains constant at the photoproduction value out to Q2>2 GeV2.

4 data tables
Table 1

THE ABSOLUTE TOTAL CROSS SECTION IS FROM A FIT TO THE MIT-SLAC ELECTRON SCATTERING DATA BY W. ATWOOD AND S. STEIN.

Table 2

No description provided.

Table 3

FOR 0.6 < M(PI+ PI-) < 0.9 GEV, USING THE METHOD OF MOMENTS.

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Production of Dimuons in 16-GeV/c pi p Interactions

Bunnell, K. ; Duong-van, Minh ; Kogan, E. ; et al.
Phys.Rev.Lett. 40 (1978) 136, 1978.
Inspire Record 121404 DOI 10.17182/hepdata.20920

A clear, prompt dimuon signal has been observed in a low-statistics streamer-chamber experiment with 16-GeV/c πp interactions. The good mass resolution makes it possible to identify the contributions from ρ and ω decays and η and ω Dalitz decays. An excess of events is observed in the mass region ∼400-600 MeV which is not accounted for by the above-mentioned decays.

1 data table
Table 1

The data with PI+- beam obtained from the combination of PI+ and PI- beams.


Structure Functions and Charge Ratios in Muon Nucleon Scattering

del Papa, C. ; Dorfan, David E. ; Flatte, Stanley M. ; et al.
Phys.Rev.D 17 (1978) 2843, 1978.
Inspire Record 120025 DOI 10.17182/hepdata.24430

We present the fractional energy distributions for positive and negative hadrons produced in muon-proton and muon-neutron scattering, and ensuing charge ratios for the photon fragmentation region. Data presented for a center-of-mass energy range 2.8<W<4.5 GeV and a virtual-photon mass-squared range 0.5≤Q2≤4.5 GeV2 indicate an overall equality of summed structure functions for neutron and proton targets, which exhibit approximate independence of Q2 and ω′, Implications in terms of quark-fragmentation ideas are discussed.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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