ANALYSIS

Identification of lines

In order to properly identify the lines of the spectra, both standard stars and the VALD were utilized. After a query is submitted, it is returned with a model spectrum with the lines identified. The lines are used to compare to the unidentified spectra.  Some standard lines include the Ca II H and K which are two prominent features in each spectrum.

Chemistry, Shapes, Blends, Splits and Binaries

In order to determine the true chemistry of the star, certain spectral features must be weeded out as unusable data. Binaries are a type of star system in which two stars orbit around a common center of mass. Binary spectra show the spectra of both stars. However, it is impossible to tell which belong to which star. Blends occur when two or more lines occur at very close wavelengths. These lines often make it so that the elements which they contain are not distinguishable from one another and it is futile to attempt to determine the abundances.

Binary star system in nova formation.     Picture credit: Peoria Astronomical Society

When lines are too deep, they can become saturated. Saturation means that they have absorbed the maximum amount of light in their certain wavelengths. This means that any additional amount of the element present after the line is saturated cannot be estimated. Therefore saturated lines do not give a true representation of the elemental abundance.

In all, the lines which are the greatest use to this study are those which are smaller, clean symmetrical lines because they represent more closely a 1:1 proportion of area to elemental abundance.
 

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