  We study near-infrared (JHK) and X-ray light curves of Cyg X-3 obtained with
the 2.5-m telescope of the Caucasian Mountain Observatory of MSU SAI and
collected from RXTE ASM and MAXI archives. The light curves in the X-ray and IR
domains are strongly affected by irregular variations. However, the mean curves
are remarkably stable and qualitatively similar in both domains. This means
that the IR flux of the system originates not only from the free-free radiation
of the WR wind but also from a compact IR source located near the relativistic
companion. The shape of the mean X-ray and IR light curves suggest the
existence of two additional structures in the WR wind - a bow shock near the
relativistic companion and a so-called "clumpy trail" (Vilhu et al. 2013).
Modeling of the mean X-ray and IR light curves allowed us to obtain important
system parameters: the orbital phase of the superior conjunction of the
relativistic companion $\phi_0=-0.066\pm 0.006$, the orbital inclination angle
$i=29.5^\circ\pm 1.2^\circ$, and the WR mass-loss rate $\dot{M} = (0.96\pm
0.14)\times 10^{-5}\rm M_\odot yr^{-1}$. By using relations between $\dot{M}$
and the rate of the period change and between $\dot{M}$ and the WR mass, we
estimated the probable mass of the relativistic companion $M_{\rm C}\simeq
7.2\rm M_\odot$ which points towards the black hole hypothesis. However, this
estimate is based on the assumption of a smooth WR wind. Considering the
uncertainty associated with clumping, the mass-loss rate can be lower which
leaves room for the neutron star hypothesis.
