Large Bubble Rupture Sparks Fast Liquid Jet

The novel experimental observation of long and narrow jets shooting out in disconnecting large elongated bubbles is presented. We investigate this phenomenon by carrying out experiments varying the control parameters and we propose a universal scaling law for the jet velocity, which unexpectedly involves the bubble height to the power 3/2. This anomalous exponent suggests an energy focusing phenomenon. We demonstrate experimentally that this focusing is purely gravity-driven and independent of the pinch-off singularity.