The electron cross-section, often referred to as the electron scattering cross-section or simply the electron cross-section, is a term used in the fields of nuclear and particle physics to describe the likelihood of electrons interacting with other particles, such as atomic nuclei or other electrons, when they are subjected to various types of scattering experiments or interactions.
The electron cross-section is typically expressed in units of area, such as square meters (m²) or square femtometers (fm²), and it represents the effective target area presented by an electron for a particular type of interaction or scattering process. It is used to quantify the probability of electron interactions occurring in various experimental setups.
A circular mil (often abbreviated as cmil or kcmil) is a unit of area used primarily in the United States for measuring the cross-sectional area of a round wire or cable. It is a convenient unit for specifying the size of electrical conductors.
One circular mil is equal to the area of a circle with a diameter of one mil (1/1000th of an inch) or approximately 0.000000506707 square inches (in²). In metric units, one circular mil is approximately equal to 0.000001273 square millimeters (mm²).
Circular mils are commonly used in the American Wire Gauge (AWG) system to specify wire sizes. The AWG system assigns a unique number to each wire size, and this number is related to the wire's cross-sectional area in circular mils. For example, a larger AWG number corresponds to a smaller wire size with fewer circular mils, while a smaller AWG number corresponds to a larger wire size with more circular mils. This system allows for easy reference and selection of wire sizes for various electrical applications.