parapositronium

physics

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Parapositronium is a short-lived atom composed of an electron and a positron. It is a form of positronium where the spins of the electron and positron are oppositely directed. When parapositronium decays, it annihilates into two photons and has a mean life of about one-tenth of a nanosecond. Positronium itself is a hydrogen-like atom formed when a positron is slowed down in matter and captured by an electron. Positrons are the antiparticles of electrons, meaning they have the same mass but opposite electric charge. Matter and antimatter annihilate each other upon contact, releasing significant energy.12

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positronium
Parapositronium, in which the spins of the positron and electron are oppositely directed, decays by annihilation into two photons, with a mean life of about one-tenth of a nanosecond (or 10^-10 second; a nanosecond is 10⁻⁹ second); and orthopositronium, in which the spins are in…
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Parapositronium, in which the spins of the positron and electron are oppositely directed, decays by annihilation into two photons, with a mean life of about one-tenth of a nanosecond (or 10^-10 second; a nanosecond is 10⁻⁹ second); and orthopositronium, in which the spins are in…
Read More