For ray tracing scenes composed of primitives, systems and methods can traverse rays through an acceleration structure. The traversal can be implemented by concurrently testing a plurality of nodes of the acceleration structure for intersection with a sequence of one or more rays. Such testing can occur in a plurality of test cells. Leaf nodes of the acceleration structure can bound primitives, and a sequence primitives can be tested concurrently for intersection in the test cells against a plurality of rays that have intersected a given leaf node. Intersection testing of a particular leaf node can be deferred until a sufficient quantity of rays have been collected for that node.