  We present an extended version of a recently proposed semi-holographic model
for heavy-ion collisions, which includes self-consistent couplings between the
Yang-Mills fields of the Color Glass Condensate framework and an infrared
AdS/CFT sector, such as to guarantee the existence of a conserved
energy-momentum tensor for the combined system that is local in space and time,
which we also construct explicitly. Moreover, we include a coupling of the
topological charge density in the glasma to the same of the holographic
infrared CFT. The semi-holographic approach makes it possible to combine CGC
initial conditions and weak-coupling glasma field equations with a simultaneous
evolution of a strongly coupled infrared sector describing the soft gluons
radiated by hard partons. As a first numerical test of the semi-holographic
model we study the dynamics of fluctuating homogeneous color-spin-locked
Yang-Mills fields when coupled to a homogeneous and isotropic energy-momentum
tensor of the holographic IR-CFT, and we find rapid convergence of the
iterative numerical procedure suggested earlier.
