Division of Astrophysics Colloquia

Astrophysics Colloquium

This colloquium will be given by Cristina Cabello at 13:15 in Lundmarksalen.

Title: 
"Mapping the ionizing structure of local analogues of primeval galaxies"

Abstract:

The identification and further study of local analogs of high-z galaxies is key to shedding light on the early Universe and the conditions under which the first sources reionized the intergalactic medium. Although local analogs have been historically analyzed from their integrated spectra, IFU observations can provide important insights into the interstellar medium (ISM) morphology and how the ionizing radiation escapes from these galaxies. In this talk, I will present the first results of a 2D spatially-resolved study of local analogs performed with MEGARA/GTC. We investigated the nature of a sample of reionization-era analogs through the spatial distribution analysis of their physical and kinematical properties. Using indirect indicators of LyC leakage, we found significant spatial variations in the escape fraction of ionizing radiation  (which is a signature of the ISM porosity), and compared our results with JWST observations of galaxies at z > 7. Furthermore, we provide a recipe to carefully estimate the random uncertainties associated with any parameter that can be derived using MEGARA IFU data. This work highlights the powerful capabilities of MEGARA to carry out a detailed scanning of the ionizing structure of the ISM thus providing useful hints about cosmic reionization.

Note that the colloquia are open to all members of the Division of Astrophysics, and we especially encourage master and Ph.D. students to participate.