Elemental Abundance in Stars - The Curve of Growth

Thread starter Daniel1992
Start date Dec 20, 2012
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Abundance Curve Growth Stars

In summary, the "Curve of Growth" is a plot that shows the relationship between the strength of an absorption line in a star's spectrum and the amount of an element present in the star's atmosphere. It is used to determine the elemental abundance of a star by comparing the strength of the absorption line to the expected strength for different amounts of the element. However, the accuracy of this method can be affected by factors such as signal-to-noise ratio, atmospheric conditions, and blending of absorption lines. Each element has its own unique "Curve of Growth" due to its specific absorption lines and characteristics. By analyzing the "Curve of Growth" for different elements in different types of stars, scientists can gain insight into the formation and evolution of stars.

Dec 20, 2012

Daniel1992

I am studying for my undergraduate Astrophysics module and the lectures notes say that that all abundances are measured relative, in terms of H = 12.00 by mass or number of atoms. Is this correct? I thought it was all based off of Carbon = 12. Am I missing something?

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Dec 20, 2012

mfb

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The definition of amu (used for isotope masses) depends on carbon-12, maybe you mixed those two definitions?

1. What is the "Curve of Growth" in relation to elemental abundance in stars?

The "Curve of Growth" refers to a plot of the relationship between the strength of an absorption line in a star's spectrum and the amount of an element present in the star's atmosphere. It is used to determine the elemental abundance of a star.

2. How is the "Curve of Growth" used to determine elemental abundance in stars?

By measuring the strength of an absorption line in a star's spectrum and comparing it to the expected strength of that line for different amounts of the element, scientists can determine the abundance of that element in the star's atmosphere.

3. What factors can affect the accuracy of elemental abundance measurements using the "Curve of Growth"?

The accuracy of measurements using the "Curve of Growth" can be affected by several factors, including the signal-to-noise ratio of the spectrum, the temperature and pressure of the star's atmosphere, and any blending of absorption lines from other elements.

4. How does the "Curve of Growth" differ for different elements?

The shape and slope of the "Curve of Growth" can vary for different elements, as each element has its own unique set of absorption lines and characteristics. This is why scientists must use specific curves for each element when determining abundance in stars.

5. What can the "Curve of Growth" tell us about the formation and evolution of stars?

By analyzing the "Curve of Growth" for different elements in different types of stars, scientists can gain insight into the formation and evolution of stars. For example, the presence of certain elements in a star's atmosphere can indicate the type of stellar environment in which it formed.