Convert Township (township) to Electron Cross Section (σₑ) instantly.
About these units
Township (township)
A township, as used in the U.S. Public Land Survey System (PLSS), is an area equal to 36 square miles, arranged as a 6-mile × 6-mile square. It is a cornerstone unit of American land division, originating during the late 18th-century settlement of the American frontier. Townships standardized how land was surveyed and sold, allowing the federal government to systematically divide territory for settlement, homesteading, and revenue generation. They were subdivided into 36 sections, each one square mile in area. This grid-based system profoundly shaped American geography. Roads, property lines, agricultural fields, and county boundaries in much of the Midwest and West follow township geometry. Even today, PLSS townships remain legally relevant in land deeds, zoning regulations, and cadastral surveys.
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.