  We have studied the shadow of a regular phantom black hole as photons couple
to Weyl tensor. We find that the coupling yields that photons with different
polarization directions propagate along different paths in the spacetime so
that there exits double shadow for a black hole, which is quite different from
that in the non-coupling case where only a single shadow emerges. The umbra of
black hole increases with the phantom charge and decreases with the coupling
strength. The dependence of the penumbra on the phantom charge and the coupling
strength is converse to that of the umbra. Combining with the supermassive
central object in our Galaxy, we estimated the shadow of the black hole as the
photons couple to Weyl tensor. Our results show that the coupling brings richer
behaviors of the propagation of coupled photon and the shadow of the black hole
in the regular phantom black hole spacetime.
