  Double peaked light curves are observed for some Type Ic supernovae (SNe Ic)
including LSQ14efd, iPTF15dtg and SN 2020bvc. One possible explanation of the
first peak would be shock-cooling emission from massive extended material
around the progenitor, which is produced by mass eruption or rapid expansion of
the outermost layers of the progenitor shortly before the supernova explosion.
We investigate the effects of such circumstellar matter (CSM) on the multi-band
optical light curves of SNe Ic using the radiation hydrodynamics code STELLA.
Two different SNe Ic progenitor masses at the pre-SN stage (3.93$M_\odot$ and
8.26$M_\odot$) are considered in the SN models. The adopted parameter space
consists of the CSM mass of $M_\mathrm{CSM} = 0.05 - 0.3 M_\odot$, the CSM
radius of $R_\mathrm{CSM} = 10^{13} - 10^{15}$cm and the explosion energy of
$E_\mathrm{burst} = (1.0 - 12.0)\times10^{51}$erg. We also investigate the
effects of the radioactive nickel distribution on the overall shape of the
light curve and the color evolution. Comparison of our SN models with the
double peaked SNe Ic LSQ14efd, iPTF15dtg and SN 2020bvc indicate that these
three SNe Ic had a similar CSM structure (i.e., $M_\mathrm{CSM} \approx 0.1 -
0.2 M_\odot$ and $R_\mathrm{CSM} = 10^{13} - 10^{14}~\mathrm{cm}$), which might
imply a common mechanism for the CSM formation. The implied mass loss rate of
$\dot{M} \gtrsim 1.0~M_\odot~\mathrm{yr^{-1}}$ is too high to be explained by
the previously suggested scenarios for pre-SN eruption, which calls for a novel
mechanism.
