Burst
A burst effect applies to whatever is in its area when it comes into effect, including creatures that you can’t see. It doesn’t affect creatures with total cover from the burst’s point of origin, and its effects don’t extend around corners. The default shape for a burst effect is a sphere, but some burst effects are specifically described as cone-shaped. A burst’s area defines how far from the point of origin the effect extends.
Source
Core Rulebook pg. 268
