1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Variable stars luminosity

  1. Jan 11, 2013 #1
    1. The problem statement, all variables and given/known data

    Given pulsation period in days, (surface temperature) and mass of an RR Lyra variable star. How do you find luminosity?

    2. Relevant equations

    The relevant equations seem to be for finding the luminosity of Cepheids... there are no equations for Lyrae... Other than, absolute magnitude is 49 solar masses luminosities, for all RRs.

    Should I use

    $$ \Pi \approx \sqrt{\frac{3\pi}{2 \gamma G \rho}} $$ to get L from

    $$\frac{L}{L_{\odot}} = {\left ( \frac{R}{R_{\odot}} \right )}^2 {\left ( \frac{T}{T_{\odot}} \right )}^4 $$ ?
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted