Sufficient stability criteria for plasma equilibria with tensor pressure

Sufficient stability criteria are derived which are valid in various situations for which an energy principle holds, i.e., tensor or scalar pressure, collisionless or collisional dynamics, toroidal or open-ended geometry, conducting or insulating walls, closed or ergodic magnetic field lines. These criteria reduce to well known ones in toroidal equilibria with scalar pressure. They are close to necessary criteria in low beta equilibria allowing for interchanges. Various well known favorable properties (viz., good curvature, magnetic well, negative υ″, line-tying) are recovered by considering special classes of equilibria. Since, in general, none of these properties appears to be crucial, the present criteria are capable of yielding a variety of hitherto unknown stably confined equilibria.