ABSTRACT
Mitome (2001) states that credit should be given to Yosioka and Omura (1962), researchers of acoustic radiation pressure (Yosioka and Kawasima (1955)), at Osaka University, Japan, for being the first to produce single bubble sonoluminescence (SBSL). Yosioka and Omura’s 1962 paper is in Japanese. I am grateful to Dr. Yasui for supplying me with a copy of the paper and its translation. Figure 3.1 shows the apparatus used by Yosioka and Omura (1962). G is a spherical flask about 36 cm in diameter filled with water, which was driven by the magnetostrictive oscillator M in radial mode of the second harmonic. A spherically symmetric acoustic field was formed by adjusting the volume of the water and the sound frequency. The resonance frequency ranged from 16.0 kHz to 16.2 kHz depending on the water temperature. P is a barium titanate hydrophone connected to an amplifier and frequency analyzer. Using degassed water, Yosioka and Omura (1962) often observed light with the naked eye from a bubble a few tens of percents of 1 mm diameter at the center of the flask.
