gravity darkening exponent نمای ِ تاریکش ِ گرانشی nemâ-ye târikeš-e gerâneši
*Fr.: exposant de l'assombrissement gravitationnel*
The exponent appearing in the power law that describes the
→ *effective temperature* of a → *rotating star*
as a function of the → *effective gravity*, as deduced from the
→ *von Zeipel theorem* or law. Generalizing this law, the effective
temperature is usually expressed as
*T*_{eff}∝ g_{eff}^{β}, where
β is the gravity darkening exponent with a value of 0.25. It has, however, been shown that
the relation between the effective temperature and gravity is not exactly a power law. Moreover,
the value of β = 0.25 is appropriate only in the limit of slow rotators and is
smaller for fast rotating stars (Espinosa Lara & Rieutord, 2011, A&A 533, A43). → *gravity*; → *darkening*;
→ *exponent*. |