Investigations of the attenuation coefficient of a narrow-bandwidth pulsed laser beam in water

The attenuation coefficient of a pulsed laser beam in water is investigated experimentally. It is found that the attenuation coefficient is dependent on the pulse energy and the linewidth of the laser, rather than a constant. The attenuation coefficient for a narrow linewidth laser can exceed that of a broad linewidth laser due to stimulated Brillouin scattering when the laser intensity is larger than a certain value. A theoretical analysis is provided.