mass discrepancy ناهمخوانی ِ جرم nâhamxâni-ye jerm Fr.: écart de masse For → massive stars and → supergiants,
the difference between the → spectroscopic mass and the
→ evolutionary mass. Early studies found that the spectroscopic
mass was systematically less than the evolutionary mass by as much as a factor of 2 for
supergiants. Improvements in the stellar atmosphere models (taking into account
→ line blanketing) have decreased or eliminated the size of the
discrepancy for Galactic stars. There is still a mass discrepancy for the hottest
→ O stars in the → Magellanic Clouds
(See, e.g. Massey et al. 2009, ApJ 692, 618).
For a → cluster of galaxies, the apparent difference between
the mass of the cluster obtained by using the → virial theorem,
and the mass inferred from the total luminosities of the member galaxies.
See also: → mass; → discrepancy. |
