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How do kiloelectron volts, megaelectron volts, gigaelectron volts, and teraelectron volts compare?

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Diagram of a linear proton resonance accelerator, or linac, showing protons entering from a source, passing through a series of labeled drift tubes powered by a radio-frequency source, and exiting as a beam through a cavity. — particle accelerator The accelerator is a large-diameter tube within which an electric field oscillates at a high radio frequency. Within the accelerator tube are smaller diameter metallic drift tubes, which are carefully sized and spaced to shield the protons from decelerating oscillations of the electric field. In the spaces between the drift tubes, the electric field is oriented properly to accelerate the protons in their direction of travel.

In atomic and nuclear physics, the electron volt (eV) serves as a fundamental unit of energy, representing the amount of energy an electron gains when accelerated through an electric potential difference of one volt. Because the eV is an extremely small unit, scientists use prefixes to denote larger scales of energy in particle accelerators:12

Kiloelectron volt (keV): Equals $10^{3}$ (1,000) eV.2
Megaelectron volt (MeV): Equals $10^{6}$ (1,000,000) eV.12
Gigaelectron volt (GeV): Equals $10^{9}$ (1,000,000,000) eV.12
Teraelectron volt (TeV): Equals $10^{12}$ (1,000,000,000,000) eV.12

These units provide a standardized way to measure the energy particles acquire as they are accelerated through electromagnetic fields. While early accelerators operated at lower voltages, modern machines like synchrotrons reach significantly higher energy levels, often requiring these larger units to describe the immense kinetic energy imparted to particles.23