Showing papers by "J. J. Veillet published in 1983"
TL;DR: In this paper, a search for two photons with missing energy yields an upper limit for the production of neutral particles which decay into a photon and a non-interacting particle, and constraints on the mass and the coupling strength of supersymmetric photinos are discussed.
27 citations
TL;DR: In this paper, the authors measured at PETRA the process e γ → e + hadrons at an average Q 2 value of 9 GeV 2 / c 2, and the total number of observed events attributed to this process is 215.
21 citations
TL;DR: In this paper, the dominant decays of τ leptons produced in e + e − interactions at √ s =34 GeV were investigated and the branching ratios were obtained.
19 citations
TL;DR: In this article, the authors compared first-order QCD predictions using two different models for the fragmentation of quarks and gluons, the Hoyer model and the Lund model.
18 citations
TL;DR: In this article, the rate of lepton leptons at PETRA was measured for energies of 14, 22 and 34 GeV, and a determination of the semileptonic branching ratio of the c and b quarks was given.
Abstract: The production of prompt leptons at PETRA has been measured for c.m. energies of 14, 22 and 34 GeV. The rate of prompt electrons and muons is presented, including a determination of the semileptonic branching ratio of thec andb quarks. We obtain
$$\begin{gathered} B(c \to \mu vX) = 12.3 \pm 2.9(stat) \pm 3.9(syst.){\raise0.5ex\hbox{$\scriptstyle 0$}\kern-0.1em/\kern-0.15em\lower0.25ex\hbox{$\scriptstyle {0,}$}} \hfill \\ B(b \to \mu vX) = 8.8 \pm 3.4(stat) \pm 3.5(syst.){\raise0.5ex\hbox{$\scriptstyle 0$}\kern-0.1em/\kern-0.15em\lower0.25ex\hbox{$\scriptstyle {0,}$}} \hfill \\ B(b \to evX) = 14.1 \pm 5.8(stat) \pm 3.0(syst.){\raise0.5ex\hbox{$\scriptstyle 0$}\kern-0.1em/\kern-0.15em\lower0.25ex\hbox{$\scriptstyle {0.}$}} \hfill \\ \end{gathered} $$
17 citations
TL;DR: In this article, the authors measured the process e + γ → e + l + + l −, where l is either an electron or a muon, at an average Q 2 of 9.5 GeV 2 / c 2.
15 citations
TL;DR: In this article, the axial vector coupling constants were obtained in a simultaneous fit to the three differential cross sections assuming a universal weak interaction for the charged leptons, and the results were in good agreement with predictions from the standard SU(2)×U(1) model for electroweak contributions.
Abstract: Differential cross sections fore
+e−→e
+e−, τ+, τ- measured with the CELLO detector at
$$\left\langle {\sqrt s } \right\rangle = 34.2GeV$$
have been analyzed for electroweak contributions. Vector and axial vector coupling constants were obtained in a simultaneous fit to the three differential cross sections assuming a universal weak interaction for the charged leptons. The results,v
2=−0.12±0.33 anda
2=1.22±0.47, are in good agreement with predictions from the standardSU(2)×U(1) model for
$$\sin ^2 \theta _w = 0.228$$
. Combining this result with neutrino-electron scattering data gives a unique axial vector dominated solution for the leptonic weak couplings. Assuming the validity of the standard model, a value of
$$\sin ^2 \theta _w = 0.21_{ - 0.09}^{ + 0.14}$$
is obtained for the electroweak mixing angle. Additional vector currents are not observed (C<0.031 is obtained at the 95% C.L.).
13 citations
TL;DR: In this article, the scale invariant inclusive photon and π0 cross sections atW=14, 22 and 34 GeV were measured and compared with neutral and charged pion production.
Abstract: We have measured the scale invariant inclusive photon and π0 cross sections atW=14, 22 and 34 GeV. A comparison with π± data shows no significant difference between neutral and charged pion production. Comparing the integrated cross sections in thex range 0.15
12 citations
TL;DR: Using the 3-prong decays of τ leptons observed at the CELLO detector at PETRA, the τ lifetime was determined to be 4.7( −2.9 +3.9 )×10 −13 s as mentioned in this paper.
6 citations