High resolution infra-red spectroscopy of selected G stars in the solar neighborhood

This thesis investigates the chemical compositions and evolutionary origins of two G-type stars (HD 76151 and HD 115617) in the solar neighborhood using high-resolution infrared spectroscopy. Analysis of optical (HARPS, ESPRESSO) and near-infrared (IGRINS) spectra has determined detailed abundance distributions for α-elements (O, Mg, Si, Ca, Ti), iron-group elements (Fe, Ni, Cr), and neutron-capture elements (Y, Zr), while providing solar-comparative [X/Fe] ratios. Evolutionary analysis via the MCMC method yields ages of 4.2 ± 0.7 billion years for HD 76151 and 8.1 ± 1.3 billion years for HD 115617. Kinematic and orbital dynamics analyses integrated with Gaia data confirm both stars originate from the Galactic thin disk, with birth radii of 6.1 ± 0.4 kpc and 7.3 ± 0.5 kpc, respectively. The novel atomic line list developed for the 1-2.5 μm wavelength range serves as a foundational data resource for infrared spectroscopic analyses at the Eastern Anatolia Observatory (DAG) under the national mission framework. Furthermore, the first detailed chemical abundance analyses in the infrared region presented in this study establish a methodological framework for understanding radial migration dynamics of solar-type stars.