  We study the diffusive behaviour of interacting active particles
(self-propelled) with mass $m$ in an asymmetric channel. The particles are
subjected to an external oscillatory force along the length of the channel. In
this setup, particles may exhibit rectification. In the absence of interaction,
the mean velocity $\langle v \rangle$ of the particles shows a maximum at
moderate $m$ values. It means that particles of moderate $m$ have higher
velocities than the others. However, by incorporating short-range interaction
between the particles, $\langle v \rangle$ exhibits an additional peak at lower
$m$ values, indicating that particles of lower and moderate m can be separated
simultaneously from the rest. Furthermore, by tuning the interaction strength,
the self-propelled velocity, and the parameters of the oscillatory force, one
can selectively separate the particles of lower $m$, moderate $m$, or both.
Empirical relations for estimating the optimal mass as a function of these
parameters are discussed. These findings are beneficial for separating the
particles of selective $m$ from the rest of the particles.
