  Geometrically thick accretion flows may be present in black hole X-ray
binaries observed in the low/hard state and in low-luminosity active galactic
nuclei. Unlike in geometrically thin disks, the angular momentum axis in these
sources is not expected to align with the black hole spin axis. We compute
images from three-dimensional general relativistic magnetohydrodynamic
simulations of misaligned (tilted) accretion flows using relativistic radiative
transfer, and compare the estimated locations of the radiation edge with
expectations from their aligned (untilted) counterparts. The radiation edge in
the tilted simulations is independent of black hole spin for a tilt of 15
degrees, in stark contrast to the results for untilted simulations, which agree
with the monotonic dependence on spin expected from thin accretion disk theory.
Synthetic emission line profiles from the tilted simulations depend strongly on
the observer's azimuth, and exhibit unique features such as broad "blue wings."
Coupled with precession, the azimuthal variation could generate time
fluctuations in observed emission lines, which would be a clear "signature" of
a tilted accretion flow. Finally, we evaluate the possibility that the observed
low- and high-frequency quasi-periodic oscillations (QPOs) from black hole
binaries could be produced by misaligned accretion flows. Although
low-frequency QPOs from precessing, tilted disks remains a viable option, we
find little evidence for significant power in our light curves in the frequency
range of high-frequency QPOs.
