  Transitional disks around the Herbig Ae/Be stars are fascinating targets in
the contexts of disk evolution and also planet formation. Oph IRS 48 is one of
such Herbig Ae stars, which shows an inner dust cavity and azimuthally lopsided
large dust distribution. We present new images of Oph IRS 48 at eight
mid-infrared (MIR) wavelengths from 8.59 to 24.6\,$\mu {\rm m}$ taken with the
COMICS mounted on the 8.2\,m Subaru Telescope. The N-band (7 to 13\,$\mu {\rm
m}$) images show that the flux distribution is centrally peaked with a slight
spatial extent, while the Q-band (17 to 25\,$\mu {\rm m}$) images show
asymmetric double peaks (east and west). Using 18.8 and 24.6\,$\mu$m images, we
derived the dust temperature at both east and west peaks to be 135$\pm$22 K.
Thus, the asymmetry may not be attributed to a difference in the temperature. %
thus other reason is necessary to explain the asymmetry of east and west peaks
in Q-band. Comparing our results with previous modeling works, we conclude that
the inner disk is aligned to the outer disk. A shadow casted by the optically
thick inner disk has a great influence on the morphology of MIR thermal
emission from the outer disk.

Earth and Planetary Astrophysics