1 / 7

Radiative Equilibrium

Radiative Equilibrium. The Condition of Radiative Equilibrium. Modes of Energy Transport Radiative Convective Conduction - Not important except in WD’s etc When all energy is transported by radiation the condition of radiative equilibrium applies.

derora
Download Presentation

Radiative Equilibrium

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Radiative Equilibrium

  2. The Condition of Radiative Equilibrium • Modes of Energy Transport • Radiative • Convective • Conduction - Not important except in WD’s etc • When all energy is transported by radiation the condition of radiative equilibrium applies. • Schwarzschild: τ 1 : Radiative τ> 1 : Convective • Convection is driven by Hydrogen ionization. Radaitive Equilibrium

  3. Radiative Equilibrium • The Energy Removed from the Beam: • Κν- total absorption coefficient • Total Energy Replaced In Beam: • Radiative Equilibrium Demands: Radaitive Equilibrium

  4. Flux Constancy • Take the Equation of Transfer and Integrate over all Frequencies and Solid Angles • But Under Radiative Equilibrium the Right Side = 0! • Therefore the Flux is constant with depth! • Total Flux uniquely specified for each atmosphere Radaitive Equilibrium

  5. Consider A Blackbody • A Small Opening in A TE Cavity • Total Flux is the Integral over Frequency: • Define Teff: Radaitive Equilibrium

  6. One Last Consideration Look at (*) Again Scattering has cancelled out as it puts as much energy into the beam as it takes out! Radaitive Equilibrium

  7. HR Diagram Chapter 13 – “Stellar Rotation” Böhm-Vitense – Introduction to Stellar Astrophysics Vol 1 Landolt-Börnstein Radaitive Equilibrium

More Related