Search for radiative b,-hadron decays in pp̅ collisions at √s=1.8 TeV

Authors

Darin Acosta, University of FloridaFollow
Kenneth A. Bloom, University of Nebraska-LincolnFollow
Collider Detector at Fermilab Collaboration

Document Type

Article

Date of this Version

12-31-2002

Comments

Published by American Physical Society. Phys. Rev. D 66, 112002 (2002). http://prd.aps.org. Copyright © 2002 American Physical Society. Permission to use.

Abstract

We have performed a search for radiative b-hadron decays using events produced in pp̅ collisions at √s=1.8 TeV and collected by the Collider Detector at Fermilab. The decays we considered were B̅_d⁰→K^*0(→K^-π⁺) γ, B̅_s⁰→φ(→K⁺K^-) γ, Λ_b⁰→ Λ(→pπ^-) γ, and their charge conjugates. Two independent methods to identify photons from such decays were employed. In the first method, the photon was detected in the electromagnetic calorimeter. In the second method, the photon was identified by an electron-positron pair produced through the external photon conversion before the tracking detector volume. By combining the two methods we obtain upper limits on the branching fractions for the B_d⁰, B̅_s⁰, and Λ_b⁰ radiative decays which, at the 95% confidence level, are found to be B( B̅_d⁰→K^*0 γ)<1.4×10^-4, B(B̅_s⁰→φ γ)<1.6×10^-4, and B( Λ_b⁰→ Λ γ)<1.9×10^-3.