An Etymological Dictionary of Astronomy and Astrophysics
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فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 2 Search : Bonnor-Ebert mass
Bonnor-Ebert mass
  جرم ِ بونور-ابرت   
jerm-e Bonnor-Ebert

Fr.: masse de Bonnor-Ebert   

The largest gravitationally stable mass of the → Bonnor-Ebert sphere.

After W.B. Bonnor (1956) and R. Ebert (1955); → mass.

critical Bonnor-Ebert mass
  جرم ِ پرژنی ِ بونور-ابرت   
jerm-e paržani-ye Bonnor-Ebert

Fr.: masse critique de Bonnor-Ebert   

The upper value of mass that a → Bonnor-Ebert sphere must have in order that → hydrodynamic equilibrium be maintained. This → critical mass is given by: Mcrit = 1.18 (a4/G3/2)Pext-1/2, where a = (kT/m)1/2 is the isothermal → sound speed inside the sphere, G is the → gravitational constant, and Pext the pressure of the external medium (see, e.g., F. H. Shu, 1977, ApJ 214, 488).

critical; → Bonnor-Ebert mass.