Next-to-next-to-leading order ${\cal O}(\alpha_s^4)$ results for heavy quark pair production in quark--antiquark collisions: The one-loop squared contributions

Understand

We calculate the next-to-next-to-leading order ${\cal O}(\alpha_s^4)$ one-loop squared corrections to the production of heavy quark pairs in quark-antiquark annihilations.

• These are part of the next-to-next-to-leading order ${\cal O}(\alpha_s^4)$ radiative QCD corrections to this process.
• Our results, with the full mass dependence retained, are presented in a closed and very compact form, in the dimensional regularization scheme.
• We have found very intriguing factorization properties for the finite part of the amplitudes.