  The emission spectrum from a simple accretion disk model around a compact
object is compared for the cases of a black hole (BH) and a boson star (BS)
playing the role of the central object. It was found in the past that such a
spectrum presents a hardening at high frequencies; however, here it is shown
that the self-interaction and compactness of the BS have the effect of
softening the spectrum, the less compact the star is, the softer the emission
spectrum at high frequencies. Because the mass of the boson fixes the mass of
the star and the self-interaction the compactness of the star, we find that,
for certain values of the BS parameters, it is possible to produce similar
spectra to those generated when the central object is a BH. This result
presents two important implications: (i) using this simple accretion model, a
BS can supplant a BH in the role of compact object accreting matter, and (ii)
within the assumptions of the present accretion disk model we do not find a
prediction that could help distinguish a BH from a BS with appropriate
parameters of mass and self-interaction.
