Crouch, H.R.
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A MEASUREMENT OF THE Z0 LEPTONIC PARTIAL WIDTHS AND THE FORWARD - BACKWARD ASYMMETRY

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
L3-005, 1990.
Inspire Record 294576 DOI 10.17182/hepdata.29691

None

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Rapidity Distributions of Ca + Ca, Nb + Nb, Ne + Au, and Au + Au at Bombarding Energies From 250-{MeV} to 2100-{MeV}/nucleon

Gutbrod, H.H. ; Kampert, K.H. ; Kolb, B.W. ; et al.
Z.Phys.A 337 (1990) 57-69, 1990.
Inspire Record 294773 DOI 10.17182/hepdata.2211

None

80 data tables
Table 1

THE STATISTICAL ERROR OF THE DATA CAN BE OBTAINED AS SQRT(D(N)/ D(YRAP)/NF) WHERE THE NORMALIZATION FACTOR NF = 971.

Table 2

THE STATISTICAL ERROR OF THE DATA CAN BE OBTAINED AS SQRT(D(N)/ D(YRAP)/NF) WHERE THE NORMALIZATION FACTOR NF = 1628.

Table 3

THE STATISTICAL ERROR OF THE DATA CAN BE OBTAINED AS SQRT(D(N)/ D(YRAP)/NF) WHERE THE NORMALIZATION FACTOR NF = 2135.

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Measurement of parity violation in the elastic scattering of polarized electrons from C-12

Souder, P.A. ; Holmes, R. ; Kim, D.H. ; et al.
Phys.Rev.Lett. 65 (1990) 694-697, 1990.
Inspire Record 303578 DOI 10.17182/hepdata.19917

We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from C12 nuclei. Our result is Aexpt=0.60±0.14±0.02 ppm, where the first error is statistical and the second is systematic. With a beam polarization of 0.37, we compute the isoscalar vector hadronic coupling constant γ̃ to be 0.136±0.032±0.009. The standard model predicts γ̃=0.155 at the tree level, in agreement with our data.

1 data table
Table 1

No description provided.


Measurement of $\Z^0$ Decays to Hadrons and a Precise Determination of the Number of Neutrino Species

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 237 (1990) 136-146, 1990.
Inspire Record 286423 DOI 10.17182/hepdata.29736

We have made a precise measurement of the cross section for e + e − →Z 0 →hadrons with the L3 detector at LEP, covering the s range from 88.28 to 95.04 GeV. From a fit to the Z 0 mass, total width, and the hadronic cross section to be M Z 0 =91.160 ± 0.024 (experiment) ±0.030(LEP) GeV, Γ Z 0 =2.539±0.054 GeV, and σ h ( M Z 0 )=29.5±0.7 nb. We also used the fit to the Z 0 peak cross section and the width todetermine Γ invisible =0.548±0.029 GeV, which corresponds to 3.29±0.17 species of light neutrinos. The possibility of four or more neutrino flavors is thus ruled out at the 4σ confidence level.

2 data tables
Table 1

No description provided.

Table 2

Total hadronic cross section.


Measurement of $g$(a) and $g(V$), the Neutral Current Coupling Constants to Leptons

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 236 (1990) 109-115, 1990.
Inspire Record 283470 DOI 10.17182/hepdata.29715

We have measured both the rates and the forward-backward asymmetry of ℓ + ℓ − from Z 0 →ℓ + ℓ − (where ℓ= μ , τ ) with the L3 detector. We obtained Γ ℓℓ =88±4±3 MeV and the vector neutral current coupling constant, g v =0.00±0.07 and the axial vector neutral current coupling constant, g A =−0.515±0.015.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


A Determination of the Properties of the Neutral Intermediate Vector Boson Z0

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 231 (1989) 509, 1989.
Inspire Record 282041 DOI 10.17182/hepdata.29768

We report the results of first physics runs of the L3 detector at LEP. Based on 2538 hadron events, we determined the mass m z 0 and the width Γ z 0 of the intermediate vector boson Z 0 to be m z 0 =91.132±0.057 GeV (not including the 46 MeV LEP machine energy uncertainty) and Γ z 0 =2.588±0.137 GeV. We also determined Γ invisible =0.567±0.080 GeV, corresponding to 3.42±0.48 number of neutrino flavors. We also measured the muon pair cross section and determined the branching ratio Γ μμ = Γ h =0.056±0.006. The partial width of Z 0 →e + e − is Γ ee =88±9±7 MeV.

1 data table
Table 1

No description provided.


A Measurement of the $e^+ e^- \to b \bar{b}$ Forward - Backward Charge Asymmetry at $\sqrt{s}=29$-{GeV}

The MAC collaboration Band, H.R. ; Camporesi, T. ; Chadwick, G.B. ; et al.
Phys.Lett.B 218 (1989) 369-373, 1989.
Inspire Record 276692 DOI 10.17182/hepdata.29845

High p ⊥ inclusive muon events produced in e + e − annihilations at √ s =29 GeV have been analyzed to obtain a measurement of the b b forward-backward charge asymmetry. The result A b =0.034±0.070±0.035 differs from the theoretical expectation (−0.16) unless substantial B 0  B 0 mixing is assumed.

1 data table
Table 1

No description provided.


Observation of Double $\phi$ Meson Production in the Central Region for the Reaction $p p \to p$(f) ($K^+ K^- K^+ K^-$) $p(s$) at 300-{GeV}/$c$

The WA76 collaboration Armstrong, T.A. ; Benayoun, Maurice ; Beusch, W. ; et al.
Phys.Lett.B 221 (1989) 221-226, 1989.
Inspire Record 276743 DOI 10.17182/hepdata.29825

The reaction pp→p f (K + K − K + K − )p s in which the K + K − K + K − system is centrally produced has been studied at 300 GeV/ c . φφ production has been observed and the ratio σ (φK + K − )/ σ ( φφ ) is 1.0±0.3. The cross section for central production of φφ is found to be the same at 300 GeV/ c and 85 GeV/ c . An angular analysis of the φφ system favours J P =2 + over 0 − .

1 data table
Table 1

No description provided.


A Spin Parity Analysis of the F(1) (1285) and F(1) (1420) Mesons Centrally Produced in the Reaction $p p \to p$(f) ($K^0_S K^\pm \pi^\mp$) at $p(s$) at 300-{GeV}/$c$

The WA76 collaboration Armstrong, T.A. ; Benayoun, Maurice ; Beusch, W. ; et al.
Phys.Lett.B 221 (1989) 216-220, 1989.
Inspire Record 276742 DOI 10.17182/hepdata.29828

Results are presented of an analysis of the reaction pp→p f (K S 0 K ± π ∓ )p s at 300 GeV/ c . Clear f 1 (1285) and f 1 (1420) signals are seen. A spin-parity analysis shows that both are consistent with being 1 ++ states. The f 1 (1420) is found to decay only to K ∗ K and no 0 −+ or 1 +− waves are required to describe the data. The production of the f 1 (1285) as a function of energy is not the same as that for the f 1 (1420) whose cross section is found to be constant with energy.

1 data table
Table 1

No description provided.


Transverse Momentum Distributions of Neutral Pions From Central and Peripheral $^{16}$O + Au Collisions at 200-a/{GeV}

The WA80 collaboration Albrecht, R. ; Awes, T.C. ; Baktash, C. ; et al.
Z.Phys.C 47 (1990) 367-376, 1990.
Inspire Record 276573 DOI 10.17182/hepdata.15159

The production of neutral pions by the interaction of 200A·GeV p and16O projectiles with a Au target has been studied in the pseudorapidity range 1.5≦η≦2.1. Transverse momentum spectra have been measured between 0.4 GeV/c and 3.6 GeV/c and their dependence on the centrality of the collision has been investigated. The peripheral-collision spectra display a marked change of slope with a hard component starting at about 1.8 GeV/c, in contrast to central-collision data. The data are discussed in comparison to p+p and α+α data from the ISR.

4 data tables
Table 1

Data obtained with minimum bias trigger conditions.

Table 2

Data obtained with minimum bias trigger conditions.

Table 3

Data for central collisions.

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