  This work deals with the scalar quasinormal modes using higher order WKB
method and black hole shadow in non-minimal Einstein Yang-Mills theory. To
validate the results of quasinormal modes, time domain profiles are also
investigated. We found that with an increase in the magnetic charge of the
black hole, the ring-down gravitational wave increases non-linearly and damping
rate decreases non-linearly. The presence of magnetic charge also results in a
decrease in the black hole shadow non-linearly. It is found that for large
values of the coupling parameter, the black hole changes to a solitonic
solution and the corresponding ring-down gravitational wave frequency increases
slowly with a decrease in the damping rate. For the solitonic solutions, the
shadow is also smaller. The constraints on the model parameters calculated
using shadow observations of M87* and Sgr A* and an approximate analytic
relation between quasinormal modes and shadow at the eikonal limit is
discussed.
