This is another example of a Z⁰ particle being produced by the collision and decaying into two quarks, which in turn decay into jets of particles. See the other example for a full explanation. If you zoom in closely you can see a secondary vertex, where two of the tracks appear to start from nowhere. This is where one of the particles produced in the event has moved before decaying into two more, detectable, particles. A better example would be a clearly-identified b-bbar event.

Notes for experts: Simple 2-jet event. One red track is identified as a muon in the forward muon chambers ("loose" association). There is a secondary vertex 2 mm (2D) from the primary vertex. Perhaps that makes it a B event.