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Two measurements of B0 anti-B0 mixing

The CLEO collaboration Bartelt, John E. ; Csorna, S.E. ; Egyed, Z. ; et al.

Phys.Rev.Lett. 71 (1993) 1680-1684, 1993.

Inspire Record 354226 DOI 10.17182/hepdata.47247

We have measured the B0B¯0 mixing probability, χd, using a sample of 965 000 BB¯ pairs from Υ(4S) decays. Counting dilepton events, we find χd=0.157±0.016±0.018−0.021+0.028. Using tagged B0 events, we find χd=0.149±0.023±0.019±0.010. The first (second) error is statistical (systematic). The third error reflects a ±15% uncertainty in the assumption, made in both cases, that charged and neutral B pairs contribute equally to dilepton events. We also obtain a limit on the CP impurity in the Bd0 system, ‖Re(εB0)‖<0.045 at 90% C.L.

4 data tables

Table 1

No description provided.

Table 2

Mixing parameter from counting dilepton events. CONST(N=MIXING PARAM) = 1/(1 - LAMBDA(C,N)) * (N(2LEPTON+) + N(2LEPTON-))/(N(LEPTON+,LEPTON-) + N(2LEPTON+) + N(2LEPTON-)). LAMBDA(C,N) is the fraction of dilepton events coming from B+B- decays, LAMBDA(C,N) = f(B+)*Br(B+)**2/(f(B+)*Br(B+)**2 + f(B0)*Br(B0)**2), where f(B+),f(B0) are the productiron fractions of the charged and neutral B's at the UPSI(4S), and Br(B+), Br(B0) are the semileptonic brancing fractions.

Table 3

Mixing parameter from tagged B0 events.

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A Determination of alpha-s (M (Z0)) at LEP using resummed QCD calculations

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, John ; et al.

Z.Phys.C 59 (1993) 1-20, 1993.

Inspire Record 354188 DOI 10.17182/hepdata.14427

The strong coupling constant, αs, has been determined in hadronic decays of theZ0 resonance, using measurements of seven observables relating to global event shapes, energy correlatio

7 data tables

Table 1

Data corrected for finite acceptance and resolution of the detector and for intial state photon radiation. No corrections for hadronic effects are applied.. Errors include statistical and systematic uncertainties, added in quadrature.

Table 2

Table 3

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A Study of D*+- production in Z0 decays

The OPAL collaboration Alexander, G. ; Allison, J. ; Allport, P.P. ; et al.

Phys.Lett.B 262 (1991) 341-350, 1991.

Inspire Record 315060 DOI 10.17182/hepdata.9272

In this paper an investigation of the production of D ∗ ± mesons produced in e + e − collisions at energies around the Z 0 pole is presented. Based on 115 D ∗ ± mesons with x D∗  2E D ∗ /E cm > 0.2 the properties of D ∗ mesons produced in the reaction Z 0 → c c are studied. Fixing the yield and the fragmentation function of bottom quarks to the values obtained at LEP using lepton tags, and average energy fraction of the D ∗ ± mesons from primary charmed quarks of 〈x c → D ∗ 〉 = 0.52 ± 0.03 +- 0.01 is found and Γ z 0 →c c = (323 ± 61 ± 35) MeV is determined. The first error is the combined statistical and systematic error from this experiment, and the second the total error from other sources.

2 data tables

Table 1

FD denotes the fraction of D* mesons from primary charmed quarks, derived from the fit (see text).

Table 2

No description provided.

Measurement of the cross-sections of the reactions e+ e- ---> gamma gamma and e+ e- ---> gamma gamma gamma at LEP

The OPAL collaboration Akwawy, M.Z. ; Alexander, G. ; Allison, J. ; et al.

Phys.Lett.B 257 (1991) 531-540, 1991.

Inspire Record 302587 DOI 10.17182/hepdata.29464

The cross section of the pure QED process e + e − → γγ has been measured using data accumulated during the 1989 and 1990 scans of the Z 0 resonance at LEP. Both the energy dependence and the angular distribution are in good agreement with the QED prediction. Upper limits on the branching ratios of Z 0 → γγ , Z 0 → π 0 γ and Z 0 → ηγ have been set at 1.4×10 −4 , 1.4×10 −4 and 2.0×10 −4 respectively. Lower limits on the cutoff parameters of the modified electron propagator have been found to be Λ + > 117 GeV and Λ − > 110 GeV. The reaction e + e − → γγγ has also been studied and was found to be consistent with the QED prediction. An upper limit on the branching ratio of Z 0 → γγγ has been set at 6.6 × 10 −5 . All the limits are given at 95% confidence level.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

PROPERTIES OF PROJECTILE FRAGMENTS FROM C-12 EMULSION INTERACTIONS AT 4.5.A/GEV/C

Ahmad, M.S. ; Khan, M.Q.R. ; Hasan, R. ;

Nucl.Phys.A 499 (1989) 821-836, 1989.

Inspire Record 286250 DOI 10.17182/hepdata.36940

2550 interactions of 12 C in emulsion at 4.5 A GeV / c have been used to study the properties of projectile fragments. The multiplicity and projected angular distributions of projectile fragments in different target groups have been studied. The production cross section of the reaction in which projectile 12 C breaks up into two Z = 3 fragments is found to be 6.6 × 10 −3 of the total inelastic cross section. The projected angular distributions of fragments exhibit features of limiting fragmentation. Statistically significant azimuthal correlations among fragments in the azimuthal plane indicates that the fragmenting nucleus gets a transverse momentum during the collision.

13 data tables

Table 1

No description provided.

Table 2

NUCLEUS IS CNO.

Table 3

NUCLEUS IS AGBR.

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Search for a Possible Exotic State C (1480) at the Vepp-2m Storage Ring

Aulchenko, V.M. ; Golubev, V.B. ; Dolinsky, S.I. ; et al.

JETP Lett. 45 (1987) 145-147, 1987.

Inspire Record 253283 DOI 10.17182/hepdata.2401

None

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

CHARGED HADRON PRODUCTION IN THE UPSILON REGION

Avery, P. ; Bebek, C. ; Berkelman, Karl ; et al.

PRINT-83-0867, 1983.

Inspire Record 192220 DOI 10.17182/hepdata.12222

None

3 data tables

Table 1

No description provided.

Table 2

NUMBERS ACTUALLY GIVEN IN GREEN 83 (CORNELL CONF, RED = 1291).

Table 3

NUMBERS ACTUALLY GIVEN IN GREEN 83 (CORNELL CONF, RED = 1291). FOR UPSI(4S) PROTON PRODUCTION SEE ALAM 83, PRL 51/1143/83, RED = 1271.

The D0 Spectrum From $B$ Meson Decay

The CLEO collaboration Green, J. ; Hicks, R.G. ; Sannes, F. ; et al.

Phys.Rev.Lett. 51 (1983) 347, 1983.

Inspire Record 190327 DOI 10.17182/hepdata.20493

The inclusive branching fraction for B-meson decay into D0 mesons and the momentum spectrum of the D0's have been measured. 0.8±0.2±0.2 D0 per B decay was found. The shape of the spectrum suggests an interesting picture of B-meson decay.

1 data table

Table 1

NUMBER OF D0'S FROM UPSI(4S) REGION AFTER CORRECTION FOR THE CONTINUUM CONTRIBUTION.

Observation of Semileptonic Decays of Charmed Baryons

Vella, E. ; Trilling, G. ; Abrams, G.S. ; et al.

Phys.Rev.Lett. 48 (1982) 1515, 1982.

Inspire Record 176986 DOI 10.17182/hepdata.19674

Direct electrons are observed in baryon events produced in e+e− annihilation at center-of-mass energies above the ΛcΛ¯c threshold. These events are attributed to charmed-baryon pair production and subsequent Λc semileptonic decay. Various semileptonic branching ratios of the Λc are determined, including B(Λc→e+X)=(4.5±1.7)%.

2 data tables

Table 1

ELECTRON-BARYON RATIO ABOVE AND BELOW LAMBDA/C THRESHOLD.

Table 2

No description provided.