Numerically simulating stellar pulsation using a "one zone" model

In summary, the conversation discusses a question from An Introduction to Modern Astrophysics by Carroll and Ostlie. The question involves a gaseous sphere in hydrostatic equilibrium with an ideal gas, no magnetic field, and an equation of state given by P = Kρ^γ. The conversation mentions that the question has been completed and graphs have been plotted, but the individual wants to investigate further by looking at how the graph would differ for the Sun. They are unsure of the correct value for pressure to input in order to get the desired graph. The question is then summarized, with the parts (a-d) outlined, including the derivation of an expression for density, the frequency of radial pulsations, and the behavior of density for different values of
  • #1
patrykh18
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Homework Statement
Write a code that will simulate stellar pulsation using a "one zone" model, and plot various graphs
Relevant Equations
The relevant equations are given in the image attached
The question is taken from An Introduction to Modern Astrophysics by Carroll and Ostlie. I did manage to do the entire question and plot the relevant graphs but I just want to to investigate a bit more. For example I want to look at how the graph would like in the case of the Sun. I don't know what the right value for pressure I would need to input in order to get the right graph, with the right amplitude and period. The value for P in part d of the question seems arbitrary to me.

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Any help would be appreciated. Question: Consider a gaseous sphere in hydrostatic equilibrium. Assume that the gas is ideal, with no magnetic field and that the equation of state is given by P = Kρ^γ, where γ is a constant.(a) Derive an expression for the density as a function of radius.(b) Assume that the density at the center of the sphere is ρ_c and that the sound speed is given by c_s = (γP/ρ)^1/2. Obtain an expression for the frequency of radial pulsations of the sphere.(c) Show that for small amplitudes, the frequency is independent of the amplitude.(d) Assuming that P = P_0 cos (ωt), plot the behavior of the density as a function of r for two different values of ω.
 

Related to Numerically simulating stellar pulsation using a "one zone" model

1. What is a "one zone" model for simulating stellar pulsation?

A "one zone" model is a simplified computational model used to simulate the pulsation of a star. It assumes that the entire star can be represented by a single zone with uniform physical properties, such as temperature and density.

2. How does a "one zone" model work?

A "one zone" model uses equations and algorithms to simulate the pulsation of a star based on its initial conditions and physical properties. These equations take into account factors such as energy production, energy transport, and the effects of gravity and pressure on the star.

3. What are the limitations of a "one zone" model?

One of the main limitations of a "one zone" model is that it oversimplifies the complex dynamics of a star. It does not account for variations in physical properties across different regions of the star, which can have a significant impact on its pulsations. Additionally, it does not take into account the effects of external factors such as nearby stars or interstellar matter.

4. How accurate are the results from a "one zone" model?

The accuracy of the results from a "one zone" model depends on the assumptions and approximations made in the model, as well as the quality of the initial conditions and physical properties used. While it can provide valuable insights into the behavior of stars, it may not accurately capture the complex dynamics and variations of a real star.

5. What are the applications of numerically simulating stellar pulsation using a "one zone" model?

Numerically simulating stellar pulsation using a "one zone" model can help scientists understand the internal structure and dynamics of stars, as well as predict their evolution and behavior. This can have implications for fields such as astrophysics, cosmology, and stellar formation and evolution.

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