Convert Electron Cross Section (σₑ) to Square Mile (US Survey) (mi² (US)) instantly.
About these units
Electron Cross Section (σₑ)
The electron cross section, often denoted σₑ, is not a fixed unit but rather a physical area representing the effective interaction size of an electron in scattering experiments. It is typically expressed in barns or submultiples such as square femtometers (fm²). Electron cross sections are vital in quantum electrodynamics (QED), X-ray scattering, atomic physics, and materials science. These values describe how electrons interact with photons, atoms, or other electrons, determining phenomena such as absorption, conductivity, and radiation shielding. Because electron interactions are probabilistic, σₑ provides a statistical measure of likelihood rather than a physical surface, illustrating how area units are used conceptually at quantum scales.
Square Mile (US Survey) (mi² (US))
The US survey square mile is extremely close to the international square mile but is defined using the US survey foot, a slightly different value than the international foot historically used in land surveying. This unit appears in American land deeds, cadastral maps, and federal land management documents. The Public Land Survey System (PLSS), which divided much of the western United States into townships and sections, relied heavily on survey-based square miles. Although the modern US has transitioned to the international foot (as of 2023), historical land descriptions remain legally tied to the survey-based definition, ensuring its continued relevance.