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Measurement of the Two Photon Reaction $\gamma \gamma \to \pi^+ \pi^- \pi^+ \pi^-$ at Large Values of $Q^2$

The TASSO collaboration Braunschweig, W. ; Gerhards, R. ; Kirschfink, F.J. ; et al.
Z.Phys.C 41 (1988) 353-357, 1988.
Inspire Record 250570 DOI 10.17182/hepdata.15557

The process γγ→π+π−π+π− has been investigated in reactions of the typee+e−→e+e−π+π−π+π− in the single tag mode. The range of the four momentum squared of one of the virtual photons was 0.28 GeV2/c2≦Q2≦3.6 GeV2/c2, the average being 〈Q2〉=0.92 GeV2/c2; the other photon was quasi real. The reaction is mainly described by the channels γγ→ρ0ρ0 and γγ→4π (phase space), occuring with about equal probability. TheQ2-dependence of the cross section is in agreement with the ρ form factor.

2 data tables
Table 1

Data read from graph.. Additional overall systematic error 25%.

Table 2

Data read from graph.. Additional overall systematic error 25%.. The Q**2 approx 0 datum is deduced from the earlier TASSO paper, Brandelik et al, Phys. Lett. 97B(1980)448, (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+1151> RED = 1151 </a>) on rho0 rho0 production.


CORRELATION AMONG CHARGED SECONDARY PARTICLES IN INTERACTIONS OF ANTI-NUCLEONS WITH TANTALUM NUCLEI AT A MOMENTUM OF 6.1-GEV/C

Andreev, V.F. ; Baranov, P.S. ; Levonian, S.V. ; et al.
JETP Lett. 45 (1987) 662-664, 1987.
Inspire Record 256457 DOI 10.17182/hepdata.16900

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


BELOW THRESHOLD AND NEAR THRESHOLD PRODUCTION OF ANTI-PROTONS IN COLLISIONS WITH NUCLEI

Lepikhin, Yu.B. ; Smirnitsky, V.A. ; Sheinkman, V.A. ;
JETP Lett. 46 (1987) 275-278, 1987.
Inspire Record 256006 DOI 10.17182/hepdata.16897

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.



Single Diffraction Dissociation in $\pi^+ p$ and $K^+ p$ Interactions at 250-{GeV}/$c$

The EHS/NA22 collaboration Adamus, M. ; Azhinenko, I.V. ; Almeida, F.M.L., Jr. ; et al.
Z.Phys.C 39 (1988) 301, 1988.
Inspire Record 254506 DOI 10.17182/hepdata.15646

None

1 data table
Table 1

No description provided.


Determination of the Real Part of the Isospin Even Forward Scattering Amplitude of Pion Nucleon Scattering at 55-{MeV} as a Test of Low-energy Quantum Chromodynamics

Wiedner, U. ; Goring, K. ; Jaki, J. ; et al.
Phys.Rev.Lett. 58 (1987) 648-650, 1987.
Inspire Record 246624 DOI 10.17182/hepdata.20153

The real part of the isospin-even forward-scattering amplitude of pion-nucleon scattering has been determined at a pion energy of Tπ=55 MeV by measurement of the elastic scattering of positive and negative pions on protons within the Coulomb-nuclear interference region. The value confirms the prediction of the Karlsruhe-Helsinki phase-shift analysis for that energy. These phases have been used to determine the σ term of pion-nucleon scattering by means of dispersion relations, resulting in a value for σ which is in contradiction with chiral perturbation theory of QCD.

1 data table
Table 1

PI- P cross sections normalised to the Coulomb cross section taken from the Karlesruhe-Helsinki phase shift analysis (R. Koch, E. Pietarinen (NP A336(80)331).


New Results From Asp on Single Photon Production at $\sqrt{s}$ 29-{GeV}

Hearty, C. ; Rothberg, J.E. ; Young, K.K. ; et al.
Phys.Rev.Lett. 58 (1987) 1711, 1987.
Inspire Record 244697 DOI 10.17182/hepdata.20171

This Letter reports results of a search for radiative production, by e+e− annihilation of particles that interact only weakly in matter. The search has been made in the total data set of 115 pb−1 acquired with the ASP detector at the SLAC storage ring PEP (s=29 GeV). No anomalous signal was observed. The number of generations of light neutrinos has been limited to Nν<7.5 (90% confidence level). Limits are also placed on the masses of particles predicted to exist by models of supersymmetry.

1 data table
Table 1

No description provided.


Measurement of the Weak Neutral Current Coupling Constants of the Electron and Limits on the Electromagnetic Properties of the Muon Neutrino

Abe, K. ; Ahrens, L.A. ; Amako, K. ; et al.
Phys.Rev.Lett. 58 (1987) 636-639, 1987.
Inspire Record 246621 DOI 10.17182/hepdata.20185

The weak coupling constants of the electron, gVe and gAe, are determined from measurements of the total and differential cross sections for the reaction νμe→νμe. The data also place limits of interest on the magnitudes of a neutrino charge radius and a possible neutrino magnetic dipole moment.

1 data table
Table 1

Neutrino beam 0 - 5 GeV.


An Estimate of Secondary Intranuclear Processes Contribution to Production of Cumulative Protons in $\pi^-$ C Interactions at 5-{GeV}/$c$

Asaturian, V.M. ; Gulkanian, G.R. ; Khudaverdian, A.G. ;
Sov.J.Nucl.Phys. 45 (1987) 657, 1989.
Inspire Record 248629 DOI 10.17182/hepdata.18406

The contribution of possible intranuclear secondary processes (interactions of secondary mesons with nucleons and few-nucleon systems, interactions of Δ-resonances with nucleons) to cumulative proton production in π − c interactions at 5 GeV/ c is studied. It has been found that the contribution of secondary processes makes nearly half of the inclusive cross section of cumulative proton production at momenta p p ⩽ 0.75 GeV/ c .

2 data tables
Table 1

FIRST PROTON (P=3) IS CUMULATIVE, MODEL DEPENDENT ESTIMATION.

Table 2

FIRST PROTON (P=3) IS CUMULATIVE, MODEL DEPENDENT ESTIMATION.


A Measurement of the Proton Structure Functions From Neutrino Hydrogen and Anti-neutrino Hydrogen Charged Current Interactions

The Birmingham-CERN-Imperial Coll.-MPI(Munich)-Oxford-University Coll. collaboration Jones, G.T. ; Jones, R.W.L. ; Kennedy, B.W. ; et al.
Z.Phys.C 44 (1989) 379-384, 1989.
Inspire Record 252341 DOI 10.17182/hepdata.15358

Within the framework of the quark-parton model, the quark and anti-quark structure functions of the proton have been measured by fitting them to the distributions of the events in the Bjorkeny variable. The data used form the largest sample of neutrino and antineutrino interactions on a pure hydrogen target available, and come from exposures of BEBC to the CERN wide band neutrino and antineutrino beams. It is found that the ratiodv/uv of valence quark distributions falls with increasing Bjorkenx. In the context of the quark-parton model the results constrain the isospin composition of the accompanying diquark system. Models involving scattering from diquarks are in disagreement with the data.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.