Tracking the dynamical, chemical and spectral evolution of molecular cores with PrestaLine: Gorynych

TL;DR

PrestaLine: Gorynych is a comprehensive simulation tool that models the dynamical, chemical, and spectral evolution of collapsing molecular cores, aiding interpretation of observational data across different core masses.

Contribution

It introduces an integrated numerical framework combining hydrodynamics, chemistry, and radiative transfer for detailed core evolution modeling.

Findings

Low-mass and high-mass cores show similar dynamical evolution patterns.

Chemical abundance changes sharply during the FHSC transition.

Spectral signatures reveal infall and depletion, with mass-dependent spatial features.

Abstract

We present PrestaLine: Gorynych, a comprehensive numerical tool designed to model the dynamical, chemical, and spectral evolution of collapsing molecular cores from the prestellar phase to protostellar accretion. The code integrates three key components: (1) Kamelung, a 1D hydrodynamics module simulating gravitational collapse up to first hydrostatic core (FHSC) formation followed by an accretion of envelope onto a young star; (2) Presta, a chemical evolution module post-processing density and temperature profiles to compute time-dependent molecular abundances; and (3) Uran(IA), a radiative transfer module generating synthetic molecular line spectra. We apply Gorynych to compare low-mass (5 Msun) and high-mass (50 Msun) cores, finding that their dynamical evolution is remarkably similar, with differences primarily in spatial scaling. Chemical evolution reveals sharp abundance changes during the FHSC transition, particularly for CO, H2O, and HCO+, though pre-collapse chemical initialization has minimal impact on most species. Spectral maps of 13CO(2-1), HCO+(3-2), and H2O(110--101) lines show distinct kinematic signatures of infall and depletion, with high-mass cores exhibiting spatially extended emission. Our results highlight Gorynych's utility to couple theoretical collapse models and observations, providing a framework to diagnose core evolution and initial conditions from molecular line data.