Chemical evolution of $^{26}$Al and $^{60}$Fe in the Milky Way
  We present theoretical mass estimates of $^{26}$Al and $^{60}$Fe throughout
the Galaxy, performed with a numerical chemical evolution model including
detailed nucleosynthesis prescriptions for both stable and radioactive
nuclides. We compared the results for several sets of stellar yields taken from
the literature, either for massive, low and intermediate mass stars, nova
systems (only for $^{26}$Al) and supernovae Type Ia, and then computed the
total masses of $^{26}$Al and $^{60}$Fe in the Galaxy. In particular, we have
studied the bulge and the disc of the Galaxy in a galactocentric radius range
between 0 and 22 kpc. We have assumed that the bulge (between 0 and 2 kpc)
evolved quickly suffering a strong burst of star formation, while the disc
formed more slowly and inside-out, in agreement with previous works, which
reproduced the majority of observational constraints. We have compared our
results with the $^{26}$Al mass observed by the $\gamma$-ray surveys COMPTEL
and INTEGRAL, in order to select the best model. Concerning $^{60}$Fe, for
which we do not have any observed mass value, we have just predicted its mass
to provide a theoretical prediction to be confirmed or disproved by future
observations. We have found that low and intermediate mass stars as well as
Type Ia supernovae contribute negligibly to the two isotopes, while massive
stars are the dominant source. The contribution from novae is, however,
necessary to reproduce the observed mass of $^{26}$Al, and this is a new
result. Our best model predicts $2.12$ M$_{\odot}$ of $^{26}$Al, in agreement
with observations, while for $^{60}$Fe our best mass estimate is around $\sim
1.05$ M$_{\odot}$. We have also predicted the present rate of injection of
$^{26}$Al and $^{60}$Fe in the Galaxy and compared it with previous results,
and we have predicted a larger present time injection rate along the disc,
relative to previous works.
