An Etymological Dictionary of Astronomy and Astrophysics

English-French-Persian

فرهنگ ریشه‌شناختی اخترشناسی-اخترفیزیک



galaxy main sequence
  رشته‌ی ِ فریست ِ کهکشانها  
rešte-ye farist-e kahkešânhâ
Fr.: séquence principale des galaxies  

A scaling relation between the → star formation rate (SFR) in galaxies and the total stellar mass (M) of the galaxies. This relation, colloquially called the “galaxy main sequence,” extends over several orders of magnitudes in M and out to → high redshifts, with a modest scatter of ~ 0.3 dex which includes both intrinsic scatter and measurement uncertainties. The existence of such tight scatter at all observed epochs suggests
that most galaxies assembled their stellar mass fairly steadily rather than predominantly in → starburst episodes, implying that → mergers have a sub-dominant contribution to the global star formation history (Wuyts et al., 2011 ApJ 742, 96).

See also:galaxy; → main; → sequence.