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Find the radii of the two stars

  1. Oct 6, 2010 #1
    1. The problem statement, all variables and given/known data
    From the light and velocity curves of an eclipsing, double-lined spectroscopic binary
    star system, it is determined that the orbital period is 3.15 yr, and the maximum radial
    velocities of stars A and B are 5.2 km s^-1 and 21.6 km s^-1, respectively. Furthermore,
    the time between first contact and minimum light is tb-ta = 0.45 days, while the length
    of the primary minimum is tc -tb = 0.52 days. Relative to the maximum brightness,
    the primary minimum is only 54.8% as bright, while the secondary minimum is 88.1%
    as bright
    You may assume the orbits are circular and seen perfectly edge on.

    Find the ratio of the stellar masses (mA/mB), the sum of the masses (M =
    mA + mB), and the individual masses (mA and mB).
    (b) Find the radii of the two stars. Hint: Use the speed of one star relative to the
    other and the eclipse timings given.

    2. Relevant equations
    v1=(2pie a1)/p r=a(1-e^2)/(1+ecos@) m1=(4V1^2*r1)/G

    [c]3. The attempt at a solution[/b]
    so becasue its edge on that means inclination angle is 90degrees so thats the real velocity and e = 0 too so just use these formula to find masses right?
    now for part B would i just the formula r=a(1-e^2)/(1+ecos@) to find the radii? checked in book showed this as radii but hint says to use something different i think
  2. jcsd
  3. Oct 6, 2010 #2
    nvm i think i figured it out
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