bei48482_FM

All baryons other than nucleons decay with mean lives of less than 10^9 s in a

variety of ways, but the end result is always a proton or neutron. For example, here is

one sequence which the baryon can follow in its decay:

→^0 



0 ^0

p

The ^0 and 

0 particles are successively lighter baryons than the . The and ^0

mesons themselves decay as described earlier, so the final result of the decay of the

is a proton, two electrons, four neutrinos, and two photons.

Resonance Particles

Most of the particles in Table 13.3 exist long enough to travel as distinct entities along

paths of measurable length, and their modes of decay can be observed in various devices.

482 Chapter Thirteen

One of the accelerator sections of a proton-antiproton collider at CERN. In these sections protons and

antiprotons are accelerated by alternating electric fields. Magnetic fields are used to focus the parti-

cles and to keep them in circular paths during the millions of orbits during which they gain energy.

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