HC${}_3$N, H${}^{13}$CN, and HN${}^{13}$C in molecular cores evolving towards star-forming regions

Abstract

As a work in progress, results from a chemical and physical analysis of molecular cores in early evolutionary stages concerning star formation are presented. Using archival data from the Atacama Large Millimeter Array (ALMA), a sample of 37 sources was investigated, from which spectra in the frequency range 330--350 GHz were extracted towards the central positions of the molecular cores. Transitions of HC${}_3$N, H${}^{13}$CN, and HN${}^{13}$C were analysed using Gaussian fits, obtaining peak intensities, fluxes, and line widths. The column densities of each molecule and their abundances were estimated. The behaviour of these abundances with the temperature of the region was studied, observing positive correlations for H${}^{13}$CN and HN${}^{13}$C, and none for HC${}_3$N. This study contributes to the characterisation of the initial conditions of the interstellar medium in early phases of stellar evolution.

Accepted in Boletín de la Asociación Argentina de Astronomía (March, 2026)