Corona discharge the electron-liberation is a high-energy photon from an atom within the plasma body relaxing after excitation from an earlier collision. The use of ionized neutral gas as a source of ionization is further diminished in a negative corona by the high-concentration of positive ions clustering around the curved electrode. Under other conditions, the collision of the positive species with the curved electrode can also cause electron liberation. The difference, then, between positive and negative coronas, in the matter of the generation of secondary electron avalanches, is that in a positive corona they are generated by the gas surrounding the plasma
Positive real numbers of the logarithmic scale. For purposes of international standards ISO 80000-3 the dimensionless quantities are referred to as levels. Positive real numbers In mathematics, the set of positive real numbers, formula_1, is the subset of those real numbers that are greater than zero. The non-negative real numbers, formula_2, also include zero. The symbols formula_3 and formula_4 are ambiguously used for either of these, so it safer to always specify which. In a complex plane, formula_5 is identified with the positive real axis and is usually drawn as a horizontal ray. This ray is used as reference in the polar form