  The late-time tail behavior of massive Dirac fields is investigated in the
Schwarzschild black-hole geometry and the result is compared with that of the
massive scalar fields. It is shown that in the intermediate times there are
three kinds of differences between the massive Dirac and scalar fields, (I) the
asymptotic behavior of massive Dirac fields is dominated by a decaying tail
without any oscillation, but the massive scalar field by a oscillatory inverse
power-law decaying tail, (II) the dumping exponent for the massive Dirac field
depends not only on the multiple number of the wave mode but also on the mass
of the Dirac field, while that for the massive scalar field depends on the
multiple number only, and (III) the decay of the massive Dirac field is slower
than that of the massive scalar field.
