ALMA observations of a high-density core in Taurus: dynamical gas interaction at the possible site of a multiple star formation

TL;DR

This study uses ALMA observations to explore a high-density core in Taurus, revealing complex dynamical gas interactions and structures near a very low-luminosity protostar, providing insights into early star formation processes.

Contribution

It presents high-resolution ALMA data showing dynamical gas interactions and complex structures in a starless high-density core close to protostar formation, highlighting the dynamical nature of initial star formation conditions.

Findings

Detection of a very high-density core (~10^7 cm^-3) near a low-luminosity protostar

Observation of a compact bipolar outflow with a timescale of a few hundred years

Identification of arc-like structures indicating dynamical gas interactions

Abstract

Starless dense cores eventually collapse dynamically, which forms protostars inside them, and the physical properties of the cores determine the nature of the forming protostars. We report ALMA observations of dust continuum emission and molecular rotational lines toward MC27 or L1521F, which is considered to be very close to the first protostellar core phase. We found a few starless high-density cores, one of which has a very high density of ~10^7 cm^-3, within a region of several hundred AU around a very low-luminosity protostar detected by Spitzer. A very compact bipolar outflow with a dynamical timescale of a few hundred years was found toward the protostar. The molecular line observation shows several cores with an arc-like structure, possibly due to the dynamical gas interaction. These complex structures revealed in the present observations suggest that the initial condition of star formation is highly dynamical in nature, which is considered to be a key factor in understanding fundamental issues of star formation such as the formation of multiple stars and the origin of the initial mass function of stars.