Elemental Abundance in Stars - The Curve of Growth

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

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All elemental abundances in stars are indeed measured relative to hydrogen, which is standardized at H = 12.00, not carbon. The confusion arises from the definition of atomic mass units (amu), which is based on carbon-12. While carbon-12 is used for isotope masses, the abundance scale for elements in astrophysics is anchored to hydrogen. Understanding these distinctions is crucial for accurate interpretation of stellar compositions. Clarity on these definitions enhances comprehension of elemental abundance in astrophysics.

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

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

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