Berna-Rodini, M.
E+ E- Scattering
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rivet Analysis
Determination of alpha-s and sin**2theta(w) from Measurements of the Total Hadronic Cross-Section in e+ e- Annihilation

The CELLO collaboration Behrend, H.J. ; Burger, J. ; Criegee, L. ; et al.
Phys.Lett.B 183 (1987) 400-411, 1987.
Inspire Record 236981 DOI 10.17182/hepdata.30231

We have measured the total normalized cross section R for the process e + e − → hadrons at centre-of-mass energies between 14.0 and 46.8 GeV based on an integrated luminosity of 60.3 pb −1 . The data are well described by the standard SU(3) c ⊗SU(2) L ⊗U(1) model with the production of the five known quarks. No open production of a sixth quark with charge 2/3 or 1/3 occurs below a centre-of-mass energy of 46.6 or 46.3 GeV, respectively. A fitting procedure which takes the correlations between measurements into account was used to determine the electroweak mixing angle sin 2 θ w and the strong coupling constant α s ( S ) in second-order QCD. We applied this procedure to the CELLO data and in addition included the data from other experiments at PETRA and PEP. Both fits give consistent results. The fit to the combined data yields α s (34 2 GeV 2 ) = 0.165±0.030, and sin 2 θ w = 0.236±0.020. Fixing sin 2 θ w at the world average value of 0.23 yields α s (34 2 GeV 2 ) = 0.169±0.025.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


OBSERVATION OF SCALING OF THE PHOTON STRUCTURE FUNCTION F2 (gamma) AT LOW Q**2

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.Lett. 58 (1987) 97, 1987.
Inspire Record 233595 DOI 10.17182/hepdata.20136

The structure function F2γ for a quasireal photon has been measured in the reaction ee→eeX for Q2 in the range 0.20.1. Below Q2=0.3 GeV2, scaling breaks down in accordance with the finite cross-section bound for real photons.

4 data tables
Table 1

Data read from graph.

Table 2

Data read from graph.

Table 3

Data read from graph.

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STUDY OF BARYON CORRELATIONS IN e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.Lett. 57 (1986) 3140, 1986.
Inspire Record 236028 DOI 10.17182/hepdata.20193

We report measurements of two-particle correlations in rapidity space between a p¯ or Λ¯ and an additional p, p¯, Λ, or Λ¯. We find evidence for local conservation of baryon number, and for the first time observe a pronounced anticorrelation between baryons with the same value of baryon number. Such an anticorrelation is expected in fragmentation models where the rapidity order of particles closely reflects their ‘‘color order,’’ as is the case, for example, in recent versions of the Lund string model.

1 data table
Table 1

No description provided.


Asymmetry in the Angular Distribution of Inclusive $\Lambda$ Baryons From $e^+ e^-$ Annihilations at $\sqrt{s}=29$-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Lett.B 181 (1986) 403-406, 1986.
Inspire Record 18955 DOI 10.17182/hepdata.30215

A forward-backward asymmetry A , consistent with that expected from the γ − Z 0 interference term in the process e + e − → q q , is observed in the laboratory production angular distribution of high-momentum ∧ baryons. The data were collected with the High Resolution Spectrometer at PEP. The asymmetry for ∧ baryons with fractional energy z= 2E s greater than 0.3 is A = (−23± 8 plusmn ; 2)%.

2 data tables
Table 1

No description provided.

Table 2

Data read from graph.


Observation of Charge Asymmetry in Hadron Jets From $e^+ e^-$ Annihilation at $\sqrt{s}=29$-{GeV}

Ash, W. ; Band, H. ; Camporesi, T. ; et al.
Phys.Rev.Lett. 58 (1987) 1080, 1987.
Inspire Record 231267 DOI 10.17182/hepdata.20184

A charge asymmetry has been observed in final-state jets from e+e− annihilation into hadrons at √s =29 GeV. The measured asymmetry is consistent with the prediction of electroweak theory. The product of axial-vector weak coupling constants, averaged over all quark flavors, is determined to be 〈gAegAq〉=-0.34±0.06±0.05.

1 data table
Table 1

Measured differential cross section after efficiency and radiative cross sections. THETA is the polar-angle of the thrust axis defined to be the angle between the direction of the incident positron and the thrust axis taken in the direction of the positron jet. Numerical values requested from the authors. Data are normalised to the total expected QED cross section.


rivet Analysis
Observation of Tensor and Scalar Mesons Produced in $e^+ e^-$ Annihilation at 29-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Rev.Lett. 57 (1986) 1990, 1986.
Inspire Record 18688 DOI 10.17182/hepdata.20227

The production of the tensor mesons f0(1270) and K*0(1430) and the scalar meson S(975) has been observed in e+e− annihilation at 29 GeV center-of-mass energy by use of data obtained with the high-resolution spectrometer at the SLAC e+e− storage ring PEP. The mean multiplicities for meson momenta greater than 1450 MeV/c are 〈nf0〉=0.11±0.04, 〈nK*0(1430)〉=0.10±0.06, and 〈nS〉=0.05±0.02 per hadronic event. The fragmentation functions of the tensor mesons are in good agreement with the predictions of the Webber cluster model. The data are consistent with a predominant strange-quark content on the S meson.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


COMPARISON OF THE PARTICLE FLOW IN q anti-q g AND q anti-q gamma EVENTS IN e+ e- ANNIHILATION

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.Lett. 57 (1986) 945, 1986.
Inspire Record 230224 DOI 10.17182/hepdata.38183

We compare the particle flow in the event plane of three-jet qq¯g (quark-antiquark-gluon) events with the particle flow in radiative annihilation events qq¯γ (quark-antiquark-photon) for similar kinematic configurations. In the angular region between quark and antiquark jet, we find a significant decrease in particle density for qq¯g as compared to qq¯γ. This effect is predicted in QCD as a result of destructive interference between soft-gluon radiation from quark, antiquark, and hard gluon.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Measurement of the Branching Ratio for $\Upsilon^\prime$-prime $\to \mu \mu$

Kaarsberg, T. ; Lee-Franzini, Juliet ; Lovelock, D.M.J. ; et al.
Phys.Rev.D 35 (1987) 2265, 1987.
Inspire Record 230842 DOI 10.17182/hepdata.23382

Using the CUSB-II detector at the Cornell Electron Storage Ring, we have measured Bμμ, the branching fraction into muons, of the Υ’’ meson. We find Bμμ(Υ’’)=(1.53±0.33±0.21)%, from which the Υ’’ total decay width is 25.5±5.0 keV. From this result we obtain αs=0.170−0.012+0.015, ΛMS¯=148−39+56 MeV. (MS¯ denotes the modified minimal-subtraction scheme).

1 data table
Table 1

No description provided.


rivet Analysis
A Study of the Decay $B \to \psi$ X

The CLEO collaboration Alam, M.S. ; Katayama, N. ; Kim, I.J. ; et al.
Phys.Rev.D 34 (1986) 3279, 1986.
Inspire Record 230961 DOI 10.17182/hepdata.23447

We have measured the inclusive branching ratio for B→ψX to be (1.09±0.16±0.21)%, and the exclusive branching ratios for B−→ψK− and B¯ ¯0 *0 to be (0.09±0.05)% and (0.41±0.18)%, respectively. The mass difference between neutral and charged B mesons is 1.1±2.1 MeV, while the difference between the mass of Υ(4S) and twice the mean B-meson mass is 18.5±3.0 MeV. The ψ momentum distribution implies a substantial two-body decay (in agreement with direct measurements), but also some combination of B→ψX with MX>1.5 GeV, and B→ψ’X.

2 data tables
Table 1

No error for cross-section given in text.

Table 2

No description provided.


rivet Analysis
Inclusive $\pi^0$ Production by $e^+ e^-$ Annihilation at 34.6-{GeV} Center-of-mass Energy

The TASSO collaboration Braunschweig, W. ; Gerhards, R. ; Kirschfink, F.J. ; et al.
Z.Phys.C 33 (1986) 13, 1986.
Inspire Record 230950 DOI 10.17182/hepdata.45205

The cross section for the processe+e−→π0+ anything has been measured at an average center of mass energy of 34.6 GeV for π0 energies between 0.7 and 17 GeV. The angular distribution for π0 energies larger than 2 GeV is of the formdσ/dΩ∼1+Acos2θ, withA=1.2±0.5. The ratio of π0 to π± production in the measured energy range is 2σ(π0)/(σ(π+)+σ(π−))=1.13±0.18

6 data tables
Table 1

Systematic errors included.

Table 2

Systematic errors included.

Table 3

No description provided.

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