Chemical complexity in a young Class I protostellar disk

Hot corinos are compact (<100 au), hot (> 100 K), and dense (>10^7 cm^-3) regions of solar-type protostars, characterized by a remarkable enrichment of interstellar complex organic molecules. These species are fundamental building blocks of prebiotic compounds such as amino acids. A key open question in astrochemistry is: is this organic material, synthesized during the protostellar stages, effectively inherited by forming planets, or is the chemical composition significantly reshaped? Currently, only a handful of hot corinos have been studied in detail with sufficient spatial resolution to distinguish between these scenarios. Using high-angular resolution observations from the ALMA Large Program FAUST, this work investigates the chemical complexity of the prototypical binary system L1551 IRS5 at planet-forming spatial scales (<50 au). I analyze for the first time, the spatial distribution of formamide (NH2CHO) in this source. I also analysed emission from dimethyl ether (CH3OCH3), one of the most abundant oxygen-bearing complex organic molecule, and confirmed that their emission trace a hot corino. I perform a 2D gaussian fit on the maps to determine their emitting size. By performing radiative transfer analysis under the assumption of Local Thermodynamic Equilibrium (LTE), I constrain the physical properties of the emitting gas, deriving the molecular column densities. To test the inheritance scenario, I compare the derived formamide-to-methanol ([NH2CHO]/[CH3OH]), dimethyl-to-methanol ([CH3OCH3]/[CH3OH]), and formamide-to-dimethyl ether ([NH2CHO]/[CH3OCH3]) abundance ratios with literature values from other protostars, protostellar shocks, and comets. This comparison suggests that complex organic molecules are inherited throughout the protostellar phase. However, the analysis regarding comets remains constrained by current observational limitations; therefore, I provide perspectives for future studies at higher angular resolution.