1. Introduction
The impact of a liquid drop on a quiescent liquid bath has been widely studied
due to its visual appeal and its importance in both natural processes and industrial
applications (Schotland 1960; Jayaratne & Mason 1964; Ching, Golay & Johnson
1984; Hallett & Christensen 1984; Cai 1989; Prosperetti & Oguz 1993). While
relatively straightforward to study experimentally since the advent of the high-speed
video camera, drop impact remains a challenging problem to treat analytically or to
simulate numerically. We here consider relatively low-energy impacts, in which the
droplet may rebound cleanly from the surface after a collision in which both the
droplet and bath are only weakly distorted.