Detectable signatures of stellar/rogue planet collisions?

[stargene]

[[ For the moderator: I thought I'd posted this before, but
maybe not...so, here it is... ]]

Our galaxy is now thought to host anywhere from billions to
trillions of rogue planets, with masses ranging down to about
~ one Jovian mass. While the chances of our solar system
interacting with one of these rogues over its life-time are very
minuscule, it occurs to me that the odds of one even hitting
one of our galaxy's many billions of stars may not be minuscule.

Has there been any research on the possible effects/signatures
of such rogue planet/stellar collisions? It seems unlikely, over
the short span of human civilization's existence, that any such
collisions would have occurred, and been noticed in the records.
But what might the signature look like in principle?