@blind_via I wanna say those are either alpha or beta particles... gamma radiation is much less visible in a cloud chamber, but usually can be seen by the remnants of what it hits.
Almost as bad as our Amazon drivers who fling packages at our front door then get mad when I ask them politely through the camera to please follow the delivery instructions. Then they get mad again when they walk under my carport and still don't follow the delivery instructions as I calmly and clearly tell them to follow the directions.