A significant portion of his research involved the abundance ratio of Carbon 12 and Carbon 13 on cool carbon stars.

The lack of a deep convection zone would mean that the outer layers would retain higher abundance ratios of these heavy elements.

Their hope was to find the abundance ratio between NH and OH.

The abundance ratios of the various combinations can be measured extremely accurately.

The origin of these grains is demonstrated by laboratory measurements of extremely unusual isotopic abundance ratios within the grain.

A common characteristic of these stars is that the abundance ratio of carbon to helium is always in the range of 0.3 to 1%.

This is despite wide variation of other abundance ratios in EHe stars.

A gas with cosmological abundances of hydrogen and helium is much more transparent than gas with solar abundance ratios.

The mass ratio of helium to hydrogen nuclei, 28%, is similar to the primordial elemental abundance ratio of these elements, 24%.

The ratio of their peak intensities corresponds to the relative abundance ratio of the peptides (and proteins).