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The $B_c$ mass up to order $α_s^4$

Nora Brambilla·Antonio Vairo
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Abstract

We evaluate in perturbative QCD, up to order $α_s^4$, the mass of the $B_c$. We use the so-called 1S-mass in order to improve the convergence of the perturbative series. Our result is $E(B_c)_{pert} = 6326^{+29}_{-9}$ MeV. Non-perturbative effects are discussed. A comparison with potential models seems to be consistent with non-perturbative contributions of the order $ - (40÷100)$ MeV.

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Nora Brambilla, Antonio Vairo. 2000-09-01. The $B_c$ mass up to order $α_s^4$. https://doi.org/10.1103/physrevd.62.094019

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