Extraction of alpha_s and m_Q from Onia

We briefly review how precise determinations of the strong coupling constant and of the heavy quark masses may be obtained from heavy quarkonium. Such determinations are competitive with heavy quark masses extraction from other systems and give an accurate value for the strong coupling constant at a relatively low energy scale. In particular we report about a recent determination of $\als$ from $Γ(Υ(1S) \to γX)/Γ(Υ(1S) \to X)$ with CLEO data which includes color octet contributions and avoids model dependence in the extraction. The obtained value is $\als (M_{Υ(1S)})= 0.184^{+0.015}_{-0.014}$, which corresponds to $\als(M_Z) = 0.119^{+0.006}_{-0.005}$. Future prospects for more precise extractions of the heavy quark masses and $\als$ are discussed.

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