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cross-section




A measure of the likelihood of a given process occurring in an accelerator, i.e., of particles colliding or otherwise interacting. Cross-section is expressed as an effective target area, which can be related to the quantum-mechanical probability of interacting by multiplying by factors such as the flux of particles entering the interaction region. The basic unit of cross-section for particle physics is the barn (b), equal to 10-24 cm2. Typical hadron collisions are measured in millibarns. Typical neutrino collision cross-sections are about 10-11 cm2.


Related categories

   • ATOMIC AND NUCLEAR PHYSICS
   • PARTICLE PHYSICS