Convection in white dwarf stars
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White dwarfs are some of the simplest stars. Because of their simplicity, they can be studied to learn fundamental facts about the universe. By studying them, we can learn about their progenitors, and 97% of stars end their lives a white dwarfs. These determinations, however, rely on the accuracy of our models of white dwarfs. In white dwarf science and the field of Astrophysics in general, one of the most prevalent, and least understood phenomena is convection. This paper discusses techniques for modeling convection in white dwarf stars, in particular, through an extension of the program Lcfit Theta, which attempts to find the size of convection zones. Most white dwarfs pulsate or oscillates in temperature and density during their life cycles. The oscillations can be seen from earth telescopes which record a star’s brightness as a function of time in a graph known as a ’light-curve’. These light-curves can be reproduced fairly well by a simple linear sum of sine functions corresponding to the frequencies and amplitudes at which it the star is oscillating. However, in stars where a convection zone is present at the surface, non-linear combinations of these sine functions appear in the light-curve. Lcfit Theta uses a model of these white dwarfs proposed by Montgomery which includes the effects of these convective regions, to generate synthetic light curves. By comparing these synthetic light curves to the measured stellar data, we can find the input parameters to Mongomery’s model which create a synthetic light curve that matches the data. By increasing the speed of this program dramatically, it is now possible to more fully probe the parameter space of these input parameters, especially the l and m values of the stellar modes of oscillation.