Testing Coelho's 2014 models with the MILES library

Koet, R.W. (2017) Testing Coelho's 2014 models with the MILES library. Bachelor's Thesis, Astronomy.

Preview	Text Bachelor_Thesis_Reinier_Koet_2017.pdf - Published Version Download (8MB) | Preview
	Text toestemming.pdf - Other Restricted to Backend only Download (77kB)

Abstract

Abstract: In 2014, Coelho released a theoretical stellar library, containing stellar spectra over a large range of temperatures, log(g) and [Fe/H], for two different compositions of [alpha/Fe]. In this Thesis, the spectral indices of the aforementioned theoretical library are compared to the MILES library, to test the validity of the models. This was done by calculating several spectral indices for the Coelho library and the MILES library, and plotting these against one another. It was found that the models of the Coelho library fit the Iron lines well. Also, the equivalent widths of the Balmer lines are overestimated for A-type giants. This is likely due to the non-LTE calculations of these lines. This effect also affected some of the C&N lines, which showed an increased amount of emission. Further, the results were compared to Martins & Coelho (2007), which compared the previous version of the theoretical library with observed stellar libraries. One of the differences that is seen between the found results and the results in Martins & Coelho (2007) is that in Coelho (2014) the Balmer lines in some giants are much more overestimated than in Martins & Coelho (2007). As stated above, this also affected the C&N lines, which was also not seen in Martins & Coelho. Furthermore, the models of the Iron lines have improved, especially for the colder stars.

Item Type:	Thesis (Bachelor's Thesis)
Degree programme:	Astronomy
Thesis type:	Bachelor's Thesis
Language:	English
Date Deposited:	15 Feb 2018 08:34
Last Modified:	15 Feb 2018 08:34
URI:	https://fse.studenttheses.ub.rug.nl/id/eprint/16305

Actions (login required)

View Item