Science with an ngVLA: Star-forming Filaments and Cores on a Galactic Scale

TL;DR

This paper discusses how the next-generation Very Large Array (ngVLA) can significantly improve the study of star-forming filaments and cores in molecular clouds by providing high-resolution, sensitive observations of NH3 emission, revealing gas dynamics.

Contribution

It demonstrates the potential of ngVLA to probe the detailed kinematics of dense gas in star-forming regions more efficiently than current instruments.

Findings

ngVLA can map NH3 emission in high-density regions faster than current VLA.

High-resolution observations reveal detailed gas flows within filaments and cores.

ngVLA's capabilities will enhance understanding of star formation processes.

Abstract

Continuum observations of molecular clouds have revealed a surprising amount of substructure in the form of filaments of a few pc length and cores of ~0.1 pc diameter. Understanding the evolution of these substructures towards star formation requires the kinematic and dynamical insights provided uniquely by sensitive line observations at high angular and spectral resolution. In this short paper, we describe how an ngVLA can probe effectively the dynamics of filaments and cores in nearby star-forming molecular clouds using the NH3 rotation-inversion transitions at 24 GHz. Such emission has been proven to trace well the high column density environments of star-forming cores and filaments but higher-resolution observations are needed to reveal important details of how dense gas is flowing within and onto these substructures. In particular, we describe how 150 x 18-m antennas with a maximum baseline of 1 km can be used to map sensitively NH3 emission across high column density locations in clouds in roughly an order of magnitude less time than with the current Jansky VLA.