Ahner, W.
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rivet Analysis
Charged Multiplicity Distribution in p p Interactions at ISR Energies

The Ames-Bologna-CERN-Dortmund-Heidelberg-Warsaw collaboration Breakstone, A. ; Campanini, R. ; Crawley, H.B. ; et al.
Phys.Rev.D 30 (1984) 528, 1984.
Inspire Record 196601 DOI 10.17182/hepdata.23637

The multiplicities of charged secondaries in proton-proton collisions were determined using the split-field-magnet detector at the CERN Intersecting Storage Rings (ISR). Measurements are presented on multiplicity distributions both for inelastic and non-single-diffractive events at four different energies s=30.4, 44.5, 52.6, and 62.2 GeV. The results reported here represent the first high-statistics measurement of charged multiplicity distributions at ISR energies with a magnetic detector covering nearly the full solid angle.

4 data tables
Table 1

INELASTIC EVENTS.

Table 2

NON-SINGLE-DIFFRACTIVE EVENTS.

Table 3

Moments of the multiplicity distributions for Inelastic events.

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An Improved Measurement of Electroweak Couplings From $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \mu^+ \mu^-$

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Z.Phys.C 22 (1984) 13, 1984.
Inspire Record 193787 DOI 10.17182/hepdata.2111

We present an analysis of electroweak leptonic couplings from high statistics experiments on Bhabha scattering and μ pair production at an energy of 34.5 GeV. The forward-backward charge asymmetry of the μ pairs was measured to be −0.098±0.023±0.005. The data were found to agree well with the standard theory of electroweak interaction giving sin2θW=0.27±0.07. The leptonic weak couplings were determined to begv=0.000±0.170 andgA=−0.481±0.055. The data were also used to investigate a class of composite models for leptons.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Deuteron Photodisintegration at Photon Energies Between 200-{MeV} and 700-{MeV} in Backward Direction

Althoff, K.H. ; Anton, G. ; Bour, D. ; et al.
Z.Phys.C 21 (1983) 149, 1983.
Inspire Record 192906 DOI 10.17182/hepdata.50170

The differential cross section of the deuteron photodisintegration was measured at a protion c.m. angle of 180 degrees and for photon energies between 180 and 730 MeV. The protons were detected in a magnetic spectrometer. The proton energy resolution varied between 30 MeV and 50 MeV FWHM. Since these are the first data at 180 degrees in this energy range a comparison can only be done with data from other laboratories extrapolated to 180 degrees and with theoretical predictions. The agreement with existing calculations is poor. Contributions of dibaryons to the cross section seem not to improve the situation.

1 data table
Table 1

BEAM ERROR D(E) = 50.000 MEV.


Highlights of the Reaction $\pi^- p \to \pi^- \pi^+ n$ at 100-{GeV}/$c$ and 175-{GeV}/$c$

Bromberg, C. ; Dickey, J.O. ; Fox, G.C. ; et al.
Phys.Rev.D 29 (1984) 588, 1984.
Inspire Record 13822 DOI 10.17182/hepdata.33875

We present a summary of the physics results from an experimental study of the reaction π−p→π−π+n at 100 and 175 GeV/c incident-beam momentum. Our data show the continuing dominance of one-pion exchange in these reactions with the characteristic 1Plab2 momentum dependence. We extract the pion Regge trajectory from our data on π−p→ρ0n and study the zero structure of the ππ differential cross section up to sππ=12 GeV2.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

SPHERICAL HARMONIC MOMENTS.

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$\rho^0$ Production in Deep Inelastic $\mu p$ Interactions

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 133 (1983) 370-374, 1983.
Inspire Record 192074 DOI 10.17182/hepdata.30613

Inclusive ϱ 0 meson production has been measured in 120 GeV and 280 GeV muon-proton interactions. Distributions of z and p T 2 are presented. Primary ϱ 0 production is found to be equal to that of π 0 production within errors.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Further Evidence for Charged Intermediate Vector Bosons at the SPS Collider

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.
Phys.Lett.B 129 (1983) 273-282, 1983.
Inspire Record 191741 DOI 10.17182/hepdata.30659

A sample of 52 Intermediate Vector Boson decays in the ( v e e) channel is described. They were produced at the CERN SPS Collider for an integrated luminosity of 0.136 pb −1 . Both production and decay properties fit well with expectations from the Standard Model of weak interactions. An improved value for the W mass is given and compared with the previously published value for the Z 0 mass.

1 data table
Table 1

No description provided.


rivet Analysis
Observation of Xi-, Anti-xi- Production in $e^+ e^-$ Annihilation

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 130 (1983) 340-344, 1983.
Inspire Record 192072 DOI 10.17182/hepdata.30636

We present evidence for the production of Ξ· − , Ξ − in e + e − annihilation into hadrons. Our measurements yields: 0.026 ± 0.008 (stat.) ± 0.009 (syst.) Ξ − , Ξ − per hadronic event at W ∼ 34 GeV. Using our previous measurements of Λ, Λ and p, p production we obtain the relative yields (Ξ − , Ξ − /(Λ, Λ = 0.087 ± 0.03 ( stat. ) ± 0.03 ( syst. ) and (Ξ − , Ξ − /( p , p = 0.033 ± 0.011 ( stat. ) ± 0.011 ( syst. ) .

2 data tables
Table 1

TOTAL YIELD PER HADRONIC EVENT AND COMPARISON WITH PREVIOUS TASSO MEASUREMENTS OF OTHER BARYONS PRODUCTION. EXTRAPOLATION HAS BEEN MADE TO MOMENTA LOWER THAN IN THE EXPERIMENTAL RANGE.

Table 2

NUMERICAL VALUES SUPPLIED BY P. JOOS.


Measurement of the Reaction gamma gamma ---> pi+ pi+ pi- pi- at PETRA

The CELLO collaboration Behrend, H.J. ; Fenner, H. ; Schachter, M.J. ; et al.
Z.Phys.C 21 (1984) 205, 1984.
Inspire Record 191578 DOI 10.17182/hepdata.16344

We have determined the cross section for γγ→π+π+π−π− in a way free of assumptions about the relative contributions fromρ0ρ0,ρ02π and 4π (uncorrelated phase space). We find a sharp onset above threshold and a rather high cross section of about 200 nb aroundWγγ=1.5 GeV which consists to about 40% ofρ0ρ0 production with sizeable contributions fromρ02π and 4π (PS). The total cross section as well as theρ0ρ0 content fall rather fast at higher c.m. energies. Attempts to explain this behaviour in terms of production of known resonances are not successful so far. The angular distributions do not show any significant structure pointing to resonance formation in the 4π-system. Only theρ0-meson is observed in the moment analysis. The decay distributions of theρ0 for forward produced rhos are fairly consistent with helicity conservation of the produced rhos in accordance with the VDM picture.

5 data tables
Table 1

No description provided.

Table 2

RESULTS OF DECOMPOSITION OF THE CROSS SECTION INTO RHO RHO, RHO 2PI, AND 4PI(PHASE SPACE) USING TWO WIDE W BINS. SEE TEXT OF PAPER FOR DISCUSSION OF FITS.

Table 3

RESULTS OF DECOMPOSITION OF THE CROSS SECTION INTO THE RHO RHO, RHO PI, AND 4PI (PHASE SPACE) USING SMALL W BINS. SEE TEXT OF PAPER FOR DISCUSSION OF FITS.

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A Comparison of Charged Current Cross-sections and Structure Functions for Neutrino and Anti-neutrinos Beams on Hydrogen and Neon

The BEBC TST Neutrino collaboration Parker, M.A. ; Francois, T. ; Guy, J.G. ; et al.
Nucl.Phys.B 232 (1984) 1-20, 1984.
Inspire Record 192873 DOI 10.17182/hepdata.33899

Using BEBC equipped with a hydrogen-filled neon-surrounded track-sensitive target, the charged current cross sections and structure functions of hydrogen and neon targets traversed by the same neutrinos and antineutrinos are compared directly. The measured total cross-section ratios between hydrogen and neon allow precise total cross-section values for hydrogen to be inferred. Using this normalization, the ν and ν hydrogen data are combined and the quark distributions in free nucleons, parametrised as functions of ξ, are extracted. This free-nucleon parametrisation is then compared directly with the neon data in order to measure nuclear effects such as those recently reported by the EMC collaboration. Only small effects are seen, in excellent agreement with recent SLAC data in a more similar A and q 2 range.

3 data tables
Table 1

Measured charged current total cross section.

Table 2

Measured charged current total cross section.

Table 3

AVERAGE Q**2 IS 6.9GEV**2 FOR NU AND 4.3GEV**2 FOR ANU.


Observation of Inclusive $\eta$ Production in $e^+ e^-$ Annihilation at {CM} Energies of 34-{GeV}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Phys.Lett.B 130 (1983) 454-458, 1983.
Inspire Record 191416 DOI 10.17182/hepdata.30634

The inclusive production of η mesons at CM energies around 34 GeV has been studied for e + e − annihilation into hadrons. The average number of η-mesons per event is found to be 0.72 ± 0.10 (stat.) ± 0.18 (syst.). The abundance of η's is studied as a function of event shape parameters and it is compared to the corresponding π 0 rates.

2 data tables
Table 1

No description provided.

Table 2

DATA REQUESTED FROM AUTHORS.