We consider rotating charged black holes with a scalar dilaton field and
    surrounded by plasma, and we study their shadows. The metric is obtained from
    the static solution by using the Newman-Janis algorithm. Assuming a suitable
    form for the plasma distribution, we separate the Hamilton-Jacobi equation for
    light and we derive an expression for the shape of the shadow. We present some
    examples of contours and we study their observable properties as functions of
    the charge and the dilaton coupling. We find that the presence of plasma
    introduces a dependency on the frequency, with the shadow becoming smaller as
    the frequency decreases.

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