Results of a Search for a CP-Odd Light Higgs in $\tau$-Pair Decays of the $\Upsilon$(1S) at Belle

We conduct a search for a CP-odd light Higgs, $A^0$, in a sample of $(102\pm2) \times10^{6}$ $\Upsilon(1S)$ by looking for $\Upsilon(1S) \rightarrow \gamma A^0$ radiative decays with $A^0\rightarrow\tau^+\tau^-$. No significant evidence of such decays is found. We set an 90\% confidence level upper limit on $ BR(\Upsilon(1S)\rightarrow\gamma A^0) \times BR(A^0\rightarrow\tau^+\tau^-)$ between $4.0\times10^{-6}$ to $4.5\times10^{-5}$ for $A^0$ masses ranging from 3.6 GeV to 9.3 GeV.