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Pair production watch

1. In pair production, why the particles produced curved away from each other in opposite direction in magnetic field?
2. During pair production, momentum must be conserved as there are no external forces acting on it. Both linear and angular momentum must be conserved so they "curve" away from each other in order to conserve momentum.
3. (Original post by alesha98)
In pair production, why the particles produced curved away from each other in opposite direction in magnetic field?
Charge must be conserved. In pair production, you initially have no charge (as no particles). Therefore the two particles produced (e.g. an electron and a positron) must have opposite and equal charges.

In a bubble chamber, or something similar, which is what produces those photos of the particle tracks, a magnetic field is applied. Charged particles curve in magnetic fields as the magnetic field provides a centripetal force on the particles. This force acts in opposite directions for oppositely charged particles, hence the two particles produced curve in opposite directions.
4. (Original post by NeverLucky)
During pair production, momentum must be conserved as there are no external forces acting on it. Both linear and angular momentum must be conserved so they "curve" away from each other in order to conserve momentum.

Of course angular momentum is conserved, but that's not why they follow curved paths.

They curve away because they are charges moving in a magnetic field.
5. (Original post by alesha98)
In pair production, why the particles produced curved away from each other in opposite direction in magnetic field?
In particle physics experiments, there is usually a magnetic field present. If the particles are charged, the antiparticle has opposite charge, and so they move in opposite directions. They curve because the force acts perpendicular to the motion of the particle.

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