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Particle Detectors & Radioactive Decay. PS414 Particle Physics & Cosmology Dr. Darrel Smith. Radiation vs. Particle. Radiation designates e.m. energy propagating in space. Usually x-rays and -rays. Flux of particles each having an energy E=h and momentum p=h /c.
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Particle Detectors & Radioactive Decay PS414 Particle Physics & Cosmology Dr. Darrel Smith
Radiation vs. Particle • Radiation designates e.m. energy propagating in space. • Usually x-rays and -rays. • Flux of particles each having an energy E=h and momentum p=h/c
Radiation vs. Particle • Particles are those entities of matter (energy) having: • rest mass • spin • charge • lifetime • neutrinos . . . heavy ions
Detecting particles/radiation • Detector must produce an intelligible signal when the particle/photon arrives. • All detectors are based on the electromagnetic interaction of the incoming charged particle with atoms or molecules in the detector.
Detecting particles/radiation • What about neutral particles? • Neutrons-- transfer energy to a charged particle • elastic collisions with protons, or • neutron capture. • Photons -- • low energy- Photomultiplier tubes • higher energy -- Ionization
Signal Producing Devices • Gaseous ionization instruments • ionization chambers • Geiger counters • Scintillation counters • Solid-state detectors, and • Other detectors (e.g., PMTs) • Examples of particle detectors