Convert Are (a) to Electron Cross Section (σₑ) instantly.
About these units
Are (a)
An are is a metric land unit equal to 100 m², originally invented during the development of the metric system but now largely overshadowed by the hectare (100 ares). Although rarely used independently in modern measurement, the are survives in real estate transactions in parts of Europe, where small land parcels—such as garden plots or rural homesteads—may be expressed in ares. It remains important historically, as it served as a transitional unit bridging the earliest metric innovations with modern large-scale land measurement practices.
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.