  We report on our study of radio source regions during the type II radio burst
on 2013 May 22 based on direction finding (DF) analysis of the Wind/WAVES and
STEREO/WAVES (SWAVES) radio observations at decameter-hectometric (DH)
wavelengths. The type II emission showed an enhancement that coincided with
interaction of two coronal mass ejections (CMEs) launched in sequence along
closely spaced trajectories. The triangulation of the SWAVES source directions
posited the ecliptic projections of the radio sources near the line connecting
the Sun and the STEREO-A spacecraft. The WAVES and SWAVES source directions
revealed shifts in the latitude of the radio source indicating that the spatial
location of the dominant source of the type II emission varies during the
CME-CME interaction. The WAVES source directions close to 1 MHz frequencies
matched the location of the leading edge of the primary CME seen in the images
of the LASCO/C3 coronagraph. This correspondence of spatial locations at both
wavelengths confirms that the CME-CME interaction region is the source of the
type II enhancement. Comparison of radio and white-light observations also
showed that at lower frequencies scattering significantly affects radio wave
propagation.
