Measurement of the B0 and B− meson lifetimes

doi:10.1016/0370-2693(93)90211-Y

Physics Letters B

Volume 307, Issues 1–2, 10 June 1993, Pages 194-208

https://doi.org/10.1016/0370-2693(93)90211-Y Get rights and content

Abstract

The lifetimes of the $B^{0}$ and B⁻ mesons have been measured with the ALEPH detector at LEP. Semileptonic decays of $B^{0}$ and B⁻ mesons were partially reconstructed by identifying events containing a lepton with an associated $D^{∗+} or D^{0}$ meson. The proper time of the B meson was estimated from the measured decay length and the momentum and mass of the D-lepton system. A fit to the proper time of $77 D^{∗+} ℓ^{−}$ and 77 D⁰ℓ⁻ candidates, combined with a constraint on the lifetime ratio ( $τ_{−} τ_{0}$ ) arising from the relative rates of observed $D^{∗+} ℓ^{−}$ and D⁰ℓ⁻ events, yielded the following lifetimes: $τ_{0} =1.52_{−0.18}^{+0.20} (stat.)_{−0.13}^{+0.07} (syst.) ps, τ_{−} = 1.47_{−0.19}^{+0.22} (stat.)_{−0.14}^{+0.15} (syst.) ps, τ_{−} τ_{0} = 0.96_{−0.15}^{+0.19} (stat.)_{−0.12}^{+0.18} (syst.)$ .

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Measurement of the B0 and B− meson lifetimes

Abstract

Phys. Lett. B

Phys. Lett. B

Z. Phys. C.

Phys. Lett. B

Phys. Lett. B

Phys. Lett. B

Phys. Rev.

Z. Phys. C.

Phys. Lett. B

Phys. Rev. Lett.

Z. Phys. C.

Phys. Rev. Lett.

Phys. Rev. D

DESY 92-039

Phys. Rev. D

Phys. Rev. Lett.

CERN-PPE/92-174

Phys. Lett. B

Measurement of the $B^{0}$ and B⁻ meson lifetimes