MeVGeV

MeVGeV, often written MeV–GeV or described as the MeV–GeV range, is an informal descriptor in physics referring to energy scales from roughly 1 MeV up to several GeV. It is not a formal field or unit, but a way to talk about phenomena and experiments that span two neighboring regimes: nuclear/atomic physics and low-to-mid energy particle physics.

In the MeV region, nuclear transitions, gamma decays, neutron capture, and low-energy scattering dominate. In the GeV region, hadron production, meson and baryon resonances, deep inelastic scattering, and collider phenomenology are prevalent. The overlap region near a few hundred MeV to a few GeV covers processes such as pion production thresholds around 140 MeV and the onset of more complex hadronic interactions that occur at higher GeV energies.

Astrophysics also uses MeV–GeV gamma-ray astronomy, with space telescopes detecting photons from tens of MeV to tens or hundreds of GeV (for example, Fermi-LAT covers roughly 20 MeV to >300 GeV). In experimental physics, detectors and instrumentation are adapted to this broad range: scintillators, calorimeters, and tracking detectors are designed to cover wide dynamic ranges and energy deposit patterns characteristic of both MeV and GeV events.

Usage: When literature discusses MeV–GeV physics, it is usually in contexts like bridging nuclear and particle processes or describing experimental programs that span both energy scales. The term emphasizes scale and range rather than indicating a separate subfield.