### mass-radius relation

**(mass-radius relationship)**
(model relating stellar mass and radius)

A **mass-radius relation** is an equation
relating a star's mass with its radius.
An example:

log R = 0.003 + 0.724 log M

This is a least-squares fit for data
covering main sequence stars over a
variety of masses and radii,
from data derived from eclipsing binaries
and radial velocities.

Better fits are found by limiting the
interval of mass values, such as varying the
constants based upon the mass. A plausible
break-point in the model would be the
point between the masses of stars with
significant convection and of stars without.

With the mass-luminosity relation
and color index, this relation can be used
in rough estimates of stellar parameter determination.

(*model,relation,mass,radius,stars*)
http://physics.ucsd.edu/students/courses/winter2008/managed/physics223/documents/Lecture7%13Part3.pdf

**Referenced by:**

stellar radius determination

index