Holographic thermalization at intermediate coupling

We use the AdS/CFT conjecture to investigate the thermalization of large-N(c) N = 4 super Yang-Mills plasma in the limit of large but finite 't Hooft coupling. On the gravity side, we supplement the type IIB supergravity action by the full set of O(α('3)) operators, which enables us to derive O(λ(-3/2)) corrections to the emission spectrum of prompt photons in one model of holographic thermalization. Decreasing the coupling strength from the λ = ∞ limit, we observe a qualitative change in the way the photon spectral density approaches its thermal limit as a function of the photon energy. We interpret this behavior as a sign of the thermalization pattern of the plasma shifting from top-down towards bottom-up.