farâz, bâlâ, abar-
A prefix denoting "over, above, beyond, greater than."
From L. supra "above, over, before, beyond," → super-.
Farâz "above, up, upon," → height; bâlâ "above, up, high," → height; abar-, → super-.
Fr.: couche super-eddingtonienne
In some stellar models, particularly for evolved → massive stars, such as → red supergiants, → Luminous Blue Variables, and → Wolf-Rayet stars, an outermost layer of the stellar envelope where the luminosity might exceed the → Eddington limit. This is due to the → opacity peak produced by the variation in the ionization level of hydrogen in the outer → convective envelope, beneath the surface, of very luminous stars. The opacity peak generates supra-Eddington layers and density inversion. The high opacity decreases the Eddington luminosity in these layers, possibly to fainter levels than the actual stellar luminosity. As a result, the → radiative acceleration exceeds the → gravitational acceleration leading to → mass loss enhancement (see, e.g., A. Maeder, Physics, Formation and Evolution of Rotating Stars, Springer, 2009).
→ supra-; → Eddington limit; → layer.
supra-horizontal branch star
setâre-ye farâz-e šâxe-ye ofoqi
Fr.: étoile au-dessus de la branche horizontale
A member of a rare class of objects found in → globular clusters to lie about one magnitude above and to the blue part of the → horizontal branch. These stars are identified as post → EHB stars on their way from to the → asymptotic giant branch.
→ supra-; → horizontal; → branch; → star.