The physics performance of LHCb
NUCL INSTRUM METH A 408:1 (1998) 137-145
Abstract:
The LHCb experiment is based on a single arm forward spectrometer optimized to study CP violation in the B system at the LHC. The experiment includes a dedicated trigger system, particle identification and a precise vertex determination; recent developments in these areas will be summarized. The detector will provide precise measurements of all angles of the unitarity triangle, the length of one of the sides (via B-s(0) - (B) over bar(s)(0) mixing) and the height of the triangle. The physics performance for selected channels will be reviewed. (C) 1998 Elsevier Science B.V. All rights reserved.First evidence for a charm radial excitation, D
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 426:1-2 (1998) 231-242
Abstract:
Using D *+ mesons exclusively reconstructed in the DELPHI detector at LEP, an excess of 66 ± 14(stat.) events is observed in the D *+π+ π- final state with a mass of 2637 ± 2(stat.) ± 6(syst.) MeV/c2 and a full width smaller than 15 MeV/c2 (95% C.L.). This signal is compatible with the expected decay of a radially excited D *′ (JP = 1-) meson. © 1998 Published by Elsevier Science B.V. All rights reserved.Measurement of the inclusive charmless and double-charm B branching ratios
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 426:1-2 (1998) 193-206
Abstract:
The DELPHI experiment at LEP has measured the inclusive charmless B hadron decay branching ratio, the B branching ratio into two charmed particles, and the total number of charmed particles per B decay, using the hadronic Z data taken between 1992 and 1995. The results are extracted from a fit to the b-tagging probability distribution based on the precise impact parameter measurements made using the microvertex detector. The inclusive charmless B branching ratio, including B decays into hidden charm (cc̄), is measured to be 0.033 ± 0.021. The B branching ratio into two open charmed particles is 0.136 ± 0.042. The mean number of charmed particles per B decay (including hidden charm) is 1.147 ± 0.041. After subtracting the B decay branching ratio into hidden charm, the charmless B branching ratio is found to be 0.007 ± 0.021, compatible with the Standard Model expectation. Models that predict an additional contribution to the charmless B branching ratio of 0.037 or higher are excluded with at least 95% confidence. © 1998 Elsevier Science B.V. All rights reserved.Measurement of the charged particle multiplicity of weakly decaying B hadrons
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 425:3-4 (1998) 399-412
Abstract:
From the Z decays recorded in 1994 and 1995 by the DELPHI detector at LEP, the charged particle multiplicity of weakly decaying B hadrons was measured to be: 4.97 ± 0.03 ± 0.06 excluding the K o and A decay products. © 1998 Published by Elsevier Science B.V. All rights reserved.Measurement of trilinear gauge couplings in e+e- collisions at 161 GeV and 172 GeV
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 423:1-2 (1998) 194-206