megaelektronvolts

Megaelectronvolts, often abbreviated as MeV, is a unit of energy commonly used in particle physics and nuclear physics. It is equal to one million electronvolts. An electronvolt (eV) is the amount of kinetic energy gained by an electron when it is accelerated through an electric potential difference of one volt. Therefore, one MeV is equivalent to the energy gained by an electron accelerated through one million volts.

The electronvolt itself is a very small unit of energy, so larger units like keV (kiloelectronvolts, 1000 eV) and MeV are convenient for expressing the energies of subatomic particles, photons, and nuclear reactions. For instance, the energy released in some nuclear fission reactions can be on the order of hundreds of MeV per fission event. Similarly, the kinetic energy of protons or electrons accelerated in particle accelerators like cyclotrons or synchrotrons is often measured in MeV or even GeV (gigaelectronvolts, one billion eV).

The conversion of MeV to joules, the standard SI unit of energy, is approximately 1 MeV = 1.602 x 10^-13 joules. This conversion highlights the minuscule scale of energy at the atomic and subatomic level. MeV is also used in the context of mass-energy equivalence, where the mass of a particle can be expressed in units of energy (e.g., an electron has a mass of approximately 0.511 MeV/c^2, where c is the speed of light).