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Figure 2

90% CL upper limits on the Υ(1𝑆)→𝛾𝐴⁰,𝐴⁰→invisible (a) and Υ(1𝑆)→𝛾𝐴⁰,𝐴⁰→𝜒𝜒 (b) branching fractions as a function of the 𝐴⁰ and 𝜒 masses set by BABAR.

(a)

(b)