  Recent simulations on super-Eddington accretion flows have shown that, apart
from the diffusion process, the vertical advection based on magnetic buoyancy
can be a more efficient process to release the trapped photons in the optically
thick disk. As a consequence, the radiative luminosity from the accretion disk
can be far beyond the Eddington value. Following this spirit, we revisit the
structure and radiation of hyper-accretion disks with mass accretion rates in
the range $10^{-3}\sim 10~M_{\sun}~{\rm s}^{-1}$. Our results show that, due to
the strong cooling through the vertical advection, the disk temperature becomes
lower than that in the classic model without the vertical advection process,
and therefore the neutrino luminosity from the disk is lower. On the other
hand, the gamma-ray photons released through the vertical advection can be
extremely super-Eddington. We argue that the large amount of escaped gamma-ray
photons may have more significant contribution to the primordial fireball than
the neutrino annihilation, and may hint a link between gamma-ray bursts and
kilonovae in the black hole hyper-accretion scenario.
