Description
The chemical and galactic evolution of the Universe is a fundamental question in modern astrophysics, recently advanced by observations from the JWST. These high-quality observations not only enhance our knowledge of the gas properties, also provide an opportunity to study stellar populations and their key characteristics, an area that has received less attention in much of the current research.
In this work, we separately analyze the stellar populations using techniques typically applied in low-redshift studies, and investigate the conditions of the gas. Then, we connect these results by applying models of ionization and shocks, providing a more comprehensive understanding of the interplay between the stars and gas. An ideal laboratory to study star-formation at high-redshift is EGSY8P7, a galaxy at z=8.683 with low-metallicity and high-density. We used observations from JWST-NIRSpec to explore the spatially resolved UV-optical rest-frame wavelengths. The low-resolution data provide valuable insights into the young, ionizing stellar populations, allowing us to calculate properties such as stellar mass and the effective temperature of massive stars. The high-resolution enable us to analyze the chemical abundances and the extreme conditions of the interstellar medium. Additionally, we analyse the properties of an outflow found in the same observations.
Finally, by combining the ionized and stellar properties, we constructed a comprehensive picture of star formation in this object, including the use of new diagnostic diagrams at low-abundances. With this information, we aim to investigate the role of outflows in feedback processes and develop a broader understanding of star formation in high-redshift galaxies.
