How do you extract speerate structures from a cluster of points in 2d cordinate

I have a bunch points in x,y that correspond to so physical processes. My goal to extract and group points based on the event/process the correspond to. The image attached shows a example of how the data looks like. By inspection you can clearly make out at least 2 curves that correspond to process I want. The data itself has a lot of noise and some false positive events.

I have already played around with Dbscan and it doesnt quite work the way I want, because of the tight packing it either groups them together or makes small broken up groups.

Any help would be appreciated