The dust acoustic solitary waves in dusty plasmas: Effects of ultraviolet irradiation

The effects of ultraviolet irradiation on small but finite amplitude dust-acoustic solitons, are studied by the reductive perturbation method. The self-consistent dust charge variation is taken into account. It is shown that the ultraviolet irradiation can significantly lower the magnitude of the dust negative charge, and even make the dust grains charged positively. With the growth of the dust charge, the phase velocity and the width of the solitary wave increase, whereas its amplitude decreases. The related physical mechanism is discussed