Galactic chemical evolution of planet hosting stars.


Different stellar populations retain the traces of stellar nucleosynthesis and the chemical evolution of the galaxy, with older generations of stars exhibiting higher alpha-element abundances and later generations becoming enriched with iron-peak elements.By examining the interdependence between planetary and host star parameters, one can infer the evolutionary links and chemical characteristics of circumstellar discs, stars, and their planetary companions. Numerous past investigations have confirmed that high-mass giant planets are typically found near metal-rich stars, whereas the metallicity of the stars that host low-mass planets varies widely. In that talk I will discuss my recent work in which we analyzed the detailed chemical abundances for a sample of >900 exoplanet hosting stars drawn from different radial velocity and transit surveys. This is further validated by the age of the host stars obtained from isochrone fitting and also from kinematic studies from GAIA DR3. The later enrichment of protoplanetary material with iron and iron-peak elements is also consistent with the core accretion process that led to the formation of the giant planets. A greater proportion of metals in the protoplanetary disc is favourable to rapid core growth, making the formation of massive planets feasible. This study suggests that the observed patterns in stellar abundances and planet masses are a natural consequence of the chemical evolution of the galaxy.