Next-to-leading order QCD analysis of deeply virtual Compton scattering amplitudes

We present a next-to-leading order (NLO) QCD analysis of unpolarized and polarized deeply virtual Compton scattering (DVCS) amplitudes, for two different input scenarios, in the $\overline{\mathrm{MS}}$ scheme. We illustrate and discuss the size of the NLO effects and the behavior of the amplitudes in skewedness, $\zeta ,$ and photon virtuality, $Q^2.$ In the unpolarized case, at fixed $Q^2,$ we find a remarkable effective power-law behavior in $\zeta ,$ akin to Regge factorization, over several orders of magnitude in $\zeta .$ We also quantify the ratio of real to imaginary parts of the DVCS amplitudes and their sensitivity to changes of the factorization scale.