Physics Hint 3

In the upper left quadrant just above the midline there is a left curving track which seems to disappear, then reappears a short distance away as two oppositely curving tracks that begin in the same direction. This must have been a positron which annihilated with a (nearly) stationary electron in the liquid. One of the two gamma-ray photons (which don't leave tracks since they are electrically neutral) re-materializes as an electron-positron pair a short distance away. Since the initial particle was a positron, the current is in the direction of motion (thumb direction), the force is along the radius of curvature pointing toward the center of curvature (nearly downward in the picture - palm facing direction), so the magnetic field must be into the picture (fingers direction).

 

Return to Fredonia Physics Department

Physics Department Office

121 Houghton Hall
State University of New York at Fredonia
Fredonia, NY 14063
(716) 673-3301