Lyon, A.L.
Deep Inelastic Scattering
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Bounds on the CP asymmetry in like sign dileptons from B0 anti-B0 meson decays

The CLEO collaboration Jaffe, D.E. ; Mahapatra, R. ; Masek, G. ; et al.
Phys.Rev.Lett. 86 (2001) 5000-5003, 2001.
Inspire Record 551926 DOI 10.17182/hepdata.47284

We have measured the charge asymmetry in like-sign dilepton yields from B^0 B^0-bar meson decays using the CLEO detector at the Cornell Electron Storage Ring. We find a_ll = [N(l+l+) - N(l-l-)]/[N(l+l+) + N[l-l-)] = +0.013 +/- 0.050 +/- 0.005 . We combine this result with a previous, independent measurement and obtain Re(epsilon_B)/(1+|epsilon_B|^2) = +0.0035 +/- 0.0103 +/- 0.0015 (uncertainties are statistical and systematic, respectively) for the CP impurity parameter, epsilon_B.

1 data table
Table 1

CONST(NAME=EPSILON) is CP impurity parameter.


A Measurement of the tau leptonic branching fractions

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Phys.Lett.B 357 (1995) 715-724, 1995.
Inspire Record 398321 DOI 10.17182/hepdata.48138

A sample of 25000 Z 0 → τ + τ − events collected by the DELPHI experiment at LEP in 1991 and 1992 is used to measure the leptonic branching fractions of the τ lepton. The results are B(τ → eν ν ) = (17.51 ± 0.39) % and B(τ → μν ν ) = (17.02 ± 0.31) %. The ratio of the muon and electron couplings to the weak charged current is measured to be g μ g e = 1.000 ± 0.013 , satisfying e-μ universality. The leptonic branching fraction corrected to the value for a massless lepton, assuming e-μ universality, is found to be B(τ → lν ν ) = (17.50 ± 0.25) %.

3 data tables
Table 1

Axis error includes +- 0.23/0.23 contribution (Data statistics).

Table 2

Axis error includes +- 0.19/0.19 contribution (Data statistics).

Table 3

Combined from the two branching fractions above. E-MU universality assumed.


rivet Analysis
Measurement of inclusive production of neutral hadrons from Z decays

The L3 collaboration Acciarri, M. ; Adam, A. ; Adriani, O. ; et al.
Phys.Lett.B 328 (1994) 223-233, 1994.
Inspire Record 374698 DOI 10.17182/hepdata.48189

We present a study of the inclusive production of π 0 , η, K s 0 and Λ based on 929,000 hadronic Z decays recorded with the L3 detector at LEP. The measured inclusive momentum distributions have been compared with predictions from parton shower models as well as an analytical Quantum Chromodynamics calculation. Comparing to low energy e + e - data, we find that QCD describes the energy evolution of the hadron spectrum.

10 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Measurement of inclusive eta production in hadronic decays of the Z0

The L3 collaboration Adriani, O. ; Aguilar-Benitez, M. ; Ahlen, S. ; et al.
Phys.Lett.B 286 (1992) 403-412, 1992.
Inspire Record 336180 DOI 10.17182/hepdata.29161

We present a study of the inclusive η production based on 300 000 hadronic Z 0 decays. The measured inclusive momentum distribution can be reproduced by parton shower Monte Carlo programs and also by an analytical QCD calculation. Comparing our results with low energy e + e − data, we find that QCD describes both the shape and the energy evolution of the η spectrum. The comparison of η production rates in quark- and gluon-enriched jet samples does not show statistically significant evidence for more abundant production of η mesons in gluon fragmentation.

2 data tables
Table 1

Differential cross section for inclusive eta production, normalized to the total hadronic cross section.

Table 2

Differential cross section for inclusive eta production, normalized to the total hadronic cross section.


Electroweak Parameters From a High Statistics Neutrino Nucleon Scattering Experiment

Blondel, A. ; Bockmann, P. ; Burkhardt, .H. ; et al.
Z.Phys.C 45 (1990) 361-379, 1990.
Inspire Record 287166 DOI 10.17182/hepdata.15282

The final results from the WA 1/2 neutrino experiment in the 1984 CERN 160 GeV narrow band beam are presented. The ratiosRν and\(R_{\bar v} \) of neutral to charged current interaction rates of neutrinos and antineutrinos in iron are measured to beRν=0.3072±0.0033 and\(R_{\bar v} \)=0.382±0.016. A value of the electroweak parameter sin2 θw = 1 −mW2/mZ2 is extracted fromRν. The result is sin2 θw =0.228+0.013(mc−1.5)±0.0003 (theor.) wheremc is the mass of the charmed quark in GeV formt=60 GeV,MH=100 GeV, ρ=1. CombiningRν and\(R_{\bar v} \) one obtains a value for ρ=0.991+0.023(mc−1.5)±0.020(exp.). Alternatively,Rν and\(R_{\bar v} \) yield a precise value of the ratio of intermediate vector boson massesmW/mZ=0.880−0.007(mc−1.5)±0.002(exp.)±0.002(theor.). Comparison of these results with those from direct measurements of the vector boson masses are presented. In a model-independent analysis the left- and right-handed neutral current coupling constants,gL2 andgR2, are determined.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Total Neutrino and Anti-neutrino Charged Current Cross-section Measurements in 100-{GeV}, 160-{GeV} and 200-{GeV} Narrow Band Beams

Berge, J.P. ; Blondel, A. ; Bockmann, P. ; et al.
Z.Phys.C 35 (1987) 443, 1987.
Inspire Record 246156 DOI 10.17182/hepdata.15709

Neutrino and antineutrino total charged current cross sections on iron were measured in the 100, 160, and 200 GeV narrow band beams at the CERN SPS in the energy range 10 to 200 GeV. Assuming σ/E to be constant, the values corrected for non-isoscalarity are σv/E = (0.686 ± 0.019) * 10−38 cm2/ (GeV · nucleon) and σv/E = (0.339 ± 0.010) * 10−38 cm2/ (GeV·nucleon). Between 50 and 150 GeV no energy dependence of σ/E was observed within ±3% for neutrino and ±4% for antineutrino interactions.

5 data tables
Table 1

Measured charged current total cross section.

Table 2

Measured charged current total cross section.

Table 3

No description provided.

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A Precision Measurement of sin**2theta(W) from Semileptonic Neutrino Scattering

Abramowicz, H. ; Belusevic, R. ; Blondel, A. ; et al.
Phys.Rev.Lett. 57 (1986) 298, 1986.
Inspire Record 228111 DOI 10.17182/hepdata.20208

The ratio Rν of the neutral- to charged-current cross sections of neutrinos in iron has been measured in an exposure of the CERN-Dortmund-Heidelberg-Saclay neutrino detector to a 160-GeV/c neutrino narrow-band beam at the CERN Super Proton Synchrotron. The result is Rν=0.3072±0.0025(stat)±0.0020(syst), for hadronic energy greater than 10 GeV. The electroweak mixing parameter is sin2θW=0.225±0.005(expt)±0.003(theor)+0.013(mc−1.5 GeVc2), where mc is the charm-quark mass.

1 data table
Table 1

No description provided.


Comparison of Nucleon Structure Functions in Bubble Chamber Neutrino Experiments With {QCD} Predictions

The Aachen-Bonn-CERN-Democritos-London-Oxford-Saclay collaboration Bosetti, P.C. ; Fritze, P. ; Grassler, H. ; et al.
Nucl.Phys.B 203 (1982) 362-384, 1982.
Inspire Record 177120 DOI 10.17182/hepdata.34172

None

1 data table
Table 1

ERRORS SHOWN ARE STATISTCAL. STRUCTURE FUNCTIONS COMPUTED ASSUMING CALLAN-GROSS RELATION.


Analysis of Fragmentation Functions of Narrow Band Neutrino and Anti-neutrino Interactions on an Isoscalar Target

The Aachen-Bonn-CERN-Democritos-London-Oxford-Saclay collaboration Deden, H. ; Fritze, P. ; Grassler, H. ; et al.
Nucl.Phys.B 198 (1982) 365-379, 1982.
Inspire Record 11149 DOI 10.17182/hepdata.34174

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


PRODUCTION RATIOS FOR HADRONS PRODUCED IN MUON PROTON INELASTIC SCATTERING AT 219-GEV

Proudfoot, J. ; Booth, N.E. ; Quirk, T.W. ; et al.
Phys.Rev.D 24 (1981) 2012-2015, 1981.
Inspire Record 172688 DOI 10.17182/hepdata.24051

Results on kaon, pion, and proton production in muon-proton scattering are presented for 10.2(z=Phadν) are fπ=0.764±0.028, fK=0.187±0.042, and fp=0.049±0.013. The K±π± ratios as a function of z and pT2 are presented: The ratios increase with z, and with pT2 for z<0.3.

1 data table
Table 1

No description provided.