The CLEO III Ring Imaging Cherenkov detector
NUCL INSTRUM METH A 409:1-3 (1998) 375-378
Abstract:
The CLEO detector is undergoing major improvements in conjunction with a high luminosity upgrade of the CESR e(+)e(-) collider. A novel element is a state of the art particle identification system, based on a proximity focused Ring Imaging Cherenkov detector. This detector will provide an excellent hadron identification at all the momenta relevant to the study of the decays of B mesons produced at the Upsilon(4S) resonance. Some features unique to our design will be discussed together with some results achieved on individual components. (C) 1998 Elsevier Science B.V. All rights reserved.Dijet production by color-singlet exchange at the fermilab tevatron
Physical Review Letters 80:6 (1998) 1156-1161
Abstract:
We report a new measurement of dijet production by color-singlet exchange in pp® collisions at √s = 1.8 TeV at the Fermilab Tevatron. In a sample of events with two jets of transverse energy EjetT > 20 GeV, pseudorapidity in the range 1.8 < |ηjet| < 3.5, and η1η2 < 0, we find that a fraction R = [1.13 ± 0.12(stat) ± 0.11(syst)]% has a pseudorapidity gap within |η| < 1 between the jets that can be attributed to color-singlet exchnage. The fraction R shows no significant dependence on EjetT or on the pseudorapidity separation between the jets. © 1998 American Physical Society.First search for CP violation in tau lepton decay
Physical Review Letters 81:18 (1998) 3823-3827
Abstract:
We have performed the first search for CP violation in tau lepton decay. CP violation in lepton decay does not occur in the minimal standard model but can occur in extensions such as the multi-Higgs doublet model. It appears as a characteristic difference between the τ− and τ+ decay angular distributions for the semileptonic decay modes such as τ− → K0 π− ν. We define an observable asymmetry to exploit this and find no evidence for any CP violation. © 1998 The American Physical Society.Flavor-specific inclusive B decays to charm
Physical Review Letters 80:6 (1998) 1150-1155
Abstract:
We have measured the branching fractions for B → D®X, B → D®X, and B → D®Xℓ+v. From these results and some previously measured branching fractions, we obtain B(b → cc®s) = (21.9 ± 3.7)%, B(b → sg) < 6.8% at 90% C.L., and B(D0 → K− π+ = (3.69 ± 0.20)%. Implications for the “B semileptonic decay problem� (measured branching fraction being below theoretical expectations) are discussed. With the increase in the value of B(b → cc®s) due to B → DX, the discrepancy is no longer statistically compelling. © 1998 American Physical Society.Jet pseudorapidity distribution in direct photon events in pp collisions at vs=1.8TeV
Physical Review D Particles Fields Gravitation and Cosmology 57:3 (1998) 1359-1365