HEPData Search

Showing 10 of 108 results

rivet Analysis
Exclusive Production of Proton Anti-proton Pairs in Photon-photon Collisions

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.

Phys.Lett.B 174 (1986) 350-356, 1986.

Inspire Record 231554 DOI 10.17182/hepdata.30246

Total and differential cross sections for exclusive production of proton-antiproton pairs in photon-photon collisions have been measured using the JADE detector at PETRA. The total cross section in the CM angular |cos θ ∗ | < 0.6 reaches a maximum value of 3.8 nb for a γγ invariant mass of W γγ = 2.25 GeV, and decreases rapidly for higher values of W γγ . In the range 2.0 GeV < W γγ < 2.6 GeV the angular distribution is not isotopic. The nucleons are preferentially emitted at large angles to the collision axis.

2 data tables

Table 1

Data read off graph.

Table 2

Data read off graph.

rivet Analysis
Formation of Delta (980) and A2 (1320) in Photon-photon Collisions

The Crystal Ball collaboration Antreasyan, D. ; Aschman, D. ; Besset, D. ; et al.

Phys.Rev.D 33 (1986) 1847, 1986.

Inspire Record 217547 DOI 10.17182/hepdata.23518

The reaction γγ→π0η has been investigated with the Crystal Ball detector at the DESY storage ring DORIS II. Formation of δ(980) and A2(1320) has been observed with γγ partial widths Γγγ(A2)=1.14±0.20±0.2 6 keV and Γγγ(δ)B(δ→πη)=0.19±0.07 −0.07+0.10 keV.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

rivet Analysis
A Study of Energy-energy Correlations in $e^+ e^-$ Annihilations at $\sqrt{s}=34$.6-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.

Z.Phys.C 28 (1985) 365, 1985.

Inspire Record 215869 DOI 10.17182/hepdata.16029

We present high statistics measurements of the energy-energy correlation (EEC) and its related asymmetry (AEEC) ine+e− annihilation at a c.m. energy of 34.6 GeV. We find that the energy dependence as well as the large angle behaviour of the latter are well described by perturbative QCD calculations toOα(s2). Non-perturbative effects are estimated with the help of fragmentation models in which different jet topologies are separated using (ɛ, δ) cuts, and found to be small. The extracted values of$\Lambda _{\overline {MS} }$ lie between 100 and 300 MeV.

2 data tables

Table 1

Corrected energy-energy correlation data.

Table 2

CORRECTED FORWARD-BACKWARD ASYMMETRY.

STUDY OF CUMULATIVE PROTON PRODUCTION IN NEUTRINO - NUCLEAR INTERACTIONS

Ammosov, V.V. ; Baranov, D.S. ; Ivanilov, A.A. ; et al.

IFVE-85-109, 1985.

Inspire Record 218430 DOI 10.17182/hepdata.40895

None

11 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of $e^+ e^- \to \mu^+ \mu^-$: A Test of Electroweak Theories

The Mark-J collaboration Adeva, B. ; Becker, U. ; Becker-Szendy, R. ; et al.

Phys.Rev.Lett. 55 (1985) 665, 1985.

Inspire Record 214607 DOI 10.17182/hepdata.3237

We use the reaction e+e−→μ+μ−, in the Mark J detector at the DESY high-energy e+e− collider PETRA, to test the standard electroweak theory and find good agreement. We also set limits on the parameters of several extended gauge theories.

6 data tables

Table 1

CROSS SECTION MEASUREMENT RELATIVE TO PREDICTED QED CROSS SECTION.

Table 2

FORWARD-BACKWARD ASYMMETRY. THE SYSTEMATIC ERROR IN THE ASYMMETRY IS <0.5 PCT.

Table 3

ANGULAR DISTRIBUTIONS NOT GIVEN IN PAPER. SUPPLIED BY E.DEFFUR.

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New Results on the Reaction $e^+ e^- \to \mu^+ \mu^-$ at $\sqrt{s}=29$-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.

Phys.Rev.D 31 (1985) 2352, 1985.

Inspire Record 212767 DOI 10.17182/hepdata.3935

We have measured the process e+e−→μ+μ− at √s =29 GeV using the High Resolution Spectrometer at SLAC PEP. The forward-backward charge asymmetry is Aμμ=-(4.9±1.5±0.5)% based on 5057 events. A subsample of 3488 μ+μ− events in the angular range ‖cosθ‖<0.55 gives a cross-section ratio of Rμμ=0.990±0.017±0.030. The resulting couplings of the weak neutral current are gaegaμ=0.208±0.064± 0.021 and gvegvμ=0.027 ±0.051±0.089. The QED cutoff parameters are Λ+>170 GeV and Λ−>146 GeV at 95% C.L.

4 data tables

Table 1

Corrected for acceptance and O(alpha**3) QED radiation. Numerical values taken from SUGANO-ANL-HEP-CP-84-90.

Table 2

Forward-backward asymmetry based on fit to angular distribution. Result is given combined with earlier data from BENDER et al.

Table 3

No description provided.

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ON STUDY OF PION MULTIPLE PRODUCTION IN NONDIFFRACTIVE EXCLUSIVE REACTIONS IN K- p INTERACTIONS AT 32.1-GeV/c

Patalakha, D.I. ; Bumazhnov, V.A. ; Bogolyubsky, M.Yu. ; et al.

Yad.Fiz. 42 (1985) 1403-1413, 1985.

Inspire Record 208572 DOI 10.17182/hepdata.40893

None

20 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Pion Pair Production in Photon-photon Interactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.

Z.Phys.C 26 (1984) 199, 1984.

Inspire Record 204487 DOI 10.17182/hepdata.16198

The processγγπ+π− has been measured with complete particle identification. Cross-sections are presented from near threshold up to the region of thef(1270). In the mass range 0.5–0.7 GeV, crosssections are lower than the Born term predictions and show no evidence for an ε(600). The two-photon width of thef(1270) is found to be in agreement with previous results.

1 data table

Table 1

Data for W > 1 GeV read from graph.. Additional overall systematic error 10% for W < 1 GeV, rising to 20% for the 4 lowest W points.

A Measurement of the Electroweak Induced Charge Asymmetry in e+ e- ---> B anti-B

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.

Phys.Lett.B 146 (1984) 437-442, 1984.

Inspire Record 203144 DOI 10.17182/hepdata.6565

The forward-backward charge asymmetry for the process e + e − → b b ̄ → μ ± + hadrons has been measured using the JADE detector at PETRA. An asymmetry of (−22.8 ± 6.0 ± 2.5)% was observed at an average center of mass energy of 34.6 GeV. For comparison, an asymmetry of −25.2% is expected on the basis of the standard Glashow-Salam-Weinberg model.

4 data tables

Table 1

THE VALUE OF CONST HAVE BEEN RESCALED TO DEFINITION I3(Q) = 1/2 BY OPY.

Table 2

No description provided.

Table 3

No description provided.

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