positrons
Electrons' antimatter twins
Positrons are the antimatter counterparts of electrons—identical in mass but carrying a positive charge instead of negative.
When a positron meets an electron, both annihilate, converting their mass entirely into energy as gamma rays.
Positrons occur naturally in cosmic rays and certain radioactive decay, and are used medically in PET scans (positron emission tomography).
Utter, complete destruction
- antiparticlesOpposite-charge particle counterparts
- electronsNegative charges in atoms
- gamma raysHighest-frequency electromagnetic radiation
- antielectronElectron's antimatter counterpart
Dirac · Anderson · particle-antiparticle · CPT symmetry · symmetry · asymmetry · cosmology · big bang
Radiotracer-based internal imaging
- tomographyImaging via cross-sections
- detectorDevice that senses
- gamma raysHighest-frequency electromagnetic radiation
- annihilationUtter, complete destruction
oncology · neurology · cardiology · diagnostic imaging · isotope · metabolism · tumor detection · brain mapping
Negative subatomic particle
- antiparticleOpposite-charge subatomic twin
- leptonFundamental particle without strong interactions
- subatomicSmaller than atoms
- particleMinute piece of matter
beta decay · weak force · fermion · quantum · spin · charge · nucleus · radioactive decay
Magnetized rotating neutron emitter
- cosmic raysEnergetic particles from beyond
- jetsPressurized fluid streams
- accretionGrowth through external addition
- neutron starUltradense stellar remnant
magnetar · solar flares · galactic · interstellar · high-energy · astrophysical
annihilation
Utter, complete destruction
- antiparticlesOpposite-charge particle counterparts
- electronsNegative charges in atoms
- gamma raysHighest-frequency electromagnetic radiation
antielectron · Dirac · Anderson · particle-antiparticle · CPT symmetry · symmetry · asymmetry · cosmology · big bang · universe
PET scan
Radiotracer-based internal imaging
- tomographyImaging via cross-sections
- detectorDevice that senses
- gamma raysHighest-frequency electromagnetic radiation
annihilation · oncology · neurology · cardiology · diagnostic imaging · isotope · metabolism · tumor detection · brain mapping · medical imaging
electron
Negative subatomic particle
- antiparticleOpposite-charge subatomic twin
- leptonFundamental particle without strong interactions
- subatomicSmaller than atoms
particle · beta decay · weak force · fermion · quantum · spin · charge · nucleus · radioactive decay · relativistic
pulsar
Magnetized rotating neutron emitter
- cosmic raysEnergetic particles from beyond
- jetsPressurized fluid streams
- accretionGrowth through external addition
neutron star · magnetar · solar flares · galactic · interstellar · high-energy · astrophysical
- high energygamma rays, cosmic rays, particle accelerator, synchrotron, neutrinos
- particleselectrons, electron, protons, proton, neutrons
- subatomic particleselectrons, protons, neutrons, photons, neutrinos
- particle physicsquark, quarks, lepton, leptons, boson
- astroparticlescosmic rays, neutrinos, gamma rays, photons, protons
- cosmic rayscosmic rays, cosmic radiation, solar rays, proton, protons