Search for the flavor-changing neutral current decay D⁰→µ ⁺µ ^- in pp̅ collisions at √s =1.96 TeV

Authors

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

Date of this Version

11-23-2003

Comments

Published by American Physical Society. Phys. Rev. D 68, 091101 (2003). http://prd.aps.org. Copyright © 2003 American Physical Society. Permission to use.

Abstract

We report on a search for the flavor-changing neutral current decay D⁰→µ⁺µ^- in pp̅ collisions at √s =1.96 TeV using 65 pb^-1 of data collected by the CDF II experiment at the Fermilab Tevatron Collider. A displaced-track trigger selects long-lived D⁰ candidates in the D⁰→µ⁺µ^- search channel, the kinematically similar D⁰→ π⁺ π^- channel used for normalization, the Cabibbo-favored D⁰→ K^-π⁺ channel used to optimize the selection criteria in an unbiased manner, and their charge conjugates. Finding no signal events in the D⁰→µ⁺µ^- search window, we set an upper limit on the branching fraction Ɓ(D⁰→µ⁺µ^-)<=2.5×10^-6 (3.3×10^-6) at the 90% (95%) confidence level.