Two-loop O(ϵ) term of 1/(mr2) heavy quarkonium potential

Abstract

As a straightforward application of the recently calculated two-loop heavy quarkonium Hamiltonian, we evaluate the two-loop O(ϵ) term of the 1/(mr2) heavy quarkonium potential. Compared to a previous calculation we find a small difference in the coefficient of the maximally non-abelian color factor CFCA2. We further examine this coefficient carefully.