Extraction of alpha_s and m_Q from Onia

TL;DR

This paper reviews methods to precisely determine the strong coupling constant and heavy quark masses from heavy quarkonium, highlighting recent results from CLEO data that include color octet effects and are model-independent.

Contribution

It presents a novel extraction of s from own(1S) decays that incorporates color octet contributions and reduces model dependence.

Findings

s(M) = 0.184^{+0.015}_{-0.014}

s(M_Z) = 0.119^{+0.006}_{-0.005}

Accurate determinations of s and m_Q from heavy quarkonium.

Abstract

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 $\Gamma(\Upsilon(1S) \to \gamma X)/\Gamma(\Upsilon(1S) \to X)$ with CLEO data which includes color octet contributions and avoids model dependence in the extraction. The obtained value is $\als (M_{\Upsilon(1S)})= 0.184^{+0.015}_{-0.014}$, 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.