I have a scene where a fleet of ships activates thier Alcubierre Type Warp Drives to flee from an enemy fleet, but unlike many sci-fi settings where a warp drive instantly pushes you up to superluminal speeds for a quick get-away, in this setting, you have to accelerate to superluminal speeds over time; so, there is a window where you can have an active warp drive, but until you break the light speed barrier, you can still be shot with conventional weapons. This means that as they flee, ships will be getting taken out by enemy lasers while technically moving at warp. So, what I want to know is how the presence of a warp bubble will effect what it looks like when these fleeing ships explode.
An Alcubierre Drive in this setting is defined as a reactionless propulsion system that manipulates space-time such that the area in front of your ship resembles an extreme positive mass density, and the area behind it an extreme negative mass density. This causes the ship to "fall" perpetually in the direction of the positive mass density. For purposes of this question, we will assume the toroidal shaped warp field represented below.
You can also assume that the Alcubierre Drive's mass density bubble is maintained by (insert clarke tech here) that if spontaneously shut off or destroyed would cause spacetime to snap back to its normally flat self at approximately the speed of light. This would presumably cause some intense gravitational waves to ripple out from the event. This does not necessarily mean that the warp drive of the ship will be the first component to fail; so debris from both before and after the warp drive fails should be considered, but the part of this event I am most interested in is the gravitational wave pattern formed by the collapse of the warp field, and what effect they would have on the debris field pattern of an exploding ship.