bubble Chamber Interactions of high energy particles produced by accelerators are studied using bubble chambers. In hydrogen bubble chamber, which is most common, liquid hydrogen is maintained at a temperature just above the boiling point, but is prevented from boiling by application of pressure. The chamber is made sensitive by suddenly reducing the pressure. Since boiling starts preferentially on the ions in the liquid, the bubbles along the path of the ionizing particles form first, making the track visible. The bubble track can be observed only for a few milli seconds, before general boiling begins throughout the liquid. The tracks are photographed using cameras, from three directions. The films obtained are scanned for interactions using scanners, which projects the films on a screen. To find the momenta of the product particles, the chamber is placed in a high magnetic field, in which particles move in a curved path. By measuring the curvatures the momenta are calculated. From the bubble density of the tracks and the momentum the identify of the particles are established.