An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A → multiple star system in which the stars can be divided into two groups, each of which traverses a larger orbit around the system's center of mass. Each of these smaller groups must also be hierarchical, which means that they must be divided into smaller subgroups which themselves are hierarchical, and so on. Hierarchical multiple systems have long-term dynamical stability.

→ hierarchical; → multiple; → system.

Consisting of, having, or involving several or many individuals, parts, elements, etc.
Math.: A number that contains another number an integral number of times without a remainder: 25 is a multiple of 5.

From Fr. multiple, from L.L. multiplus "manifold," from L. → multi- "many, much" + -plus "fold," from base of plicare "to fold, twist."

Bastâ-, from bas "many, much" (Mid.Pers. vas "many, much;" O.Pers. vasiy "at will, greatly, utterly;" Av. varəmi "I wish," vasô, vasə "at one's pleasure or will," from vas- "to will, desire, wish") + tâ "fold, plait, ply; piece, part," also a multiplicative suffix; Mid.Pers. tâg "piece, part."

The division of a relatively long exposure into several successive shorter ones, e.g. to avoid detector saturation.

→ multiple; → exposure.

A series of successive integrations in which the integral operator acts on the result of preceding integration.

→ multiple; → integral.

A process of → radiative transfer in which more than one → scattering event may be of importance before → transmission, → reflection, or → absorption. In → radiation-driven winds photon scattering can take place in different → spectral lines. Each scattering occurs in a different spectral line, and successive scatterings occur at lower energies (longer wavelength). The standard theory of line driving (→ CAK model) assumes that photons can be scattered only once in the wind, which is a reasonable assumption for normal → O stars. In → Wolf-Rayet stars, where photons evolve in an atmosphere with a strong → ionization stratification, multiple scattering is important. Indeed the strength of W-R winds appears to exceed the single scattering limit.

→ multiple; → scattering.

A star which appears single but is in fact composed of more than two components. See also → multiple star system; → binary star; → triple star.

→ multiple; → star.

A stellar system composed of several stars bound together by gravitational attraction and revolving around a common center of mass.

→ multiple; → star; → system.

1) A system consisting of several → components.
2) → multiple star system.

→ multiple; → system.

A group of spectral lines arising from transitions having a common lower energy level.

From → multi- + -plet on the model of triplet.

Bastâyé, from bastâ-→ multi- + euphonic -yé, from -é nuance suffix.

A → multiple star system that lacks the characteristics of a → hierarchical multiple system.

→ non-; → hierarchical; → multiple; → system.

A generalization of the concept of multiplet to the case when there are several quantum numbers that describe the quantum-mechanical states.

→ super-; multiplet.