Gas infall in the massive star formation core G192.16-3.84

TL;DR

This study reports the first detection of gas infall in the high-mass star-forming core G192.16-3.84, providing evidence for accretion processes consistent with high-mass star formation models.

Contribution

First observation of infall motion in G192.16-3.84 using molecular line data, supporting high accretion rates in massive star formation.

Findings

Infall velocities of 2.0 and 2.8 km/s derived from line profiles.

Mass infall rates of approximately 4.7 and 6.6 x 10^{-3} solar masses per year.

Infall rates align with turbulent core model predictions.

Abstract

Previous observations have revealed an accretion disk and outflow motion in high-mass star-forming region G192.16-3.84. While collapse have not been reported before. We present here molecular line and continuum observations toward massive core G192.16-3.84 with the Submillimeter Array. C$^{18}$O(2-1) and HCO$^{+}$(3-2) lines show pronounced blue profiles, indicating gas infalling in this region. This is the first time that the infall motion has been reported in G192.16-3.84 core. Two-layer model fitting gave infall velocities of 2.0$\pm$0.2 and 2.8$\pm$0.1 km s$^{-1}$. Assuming that the cloud core follows a power-law density profile ($\rho$$\propto$$r^{1.5}$), the corresponding mass infall rates are (4.7$\pm$1.7)$\times10^{-3}$ and (6.6$\pm$2.1)$\times10^{-3}$ M$_{\sun}$ yr$^{-1}$ for C$^{18}$O(2-1) and HCO$^{+}$(3-2), respectively. The derived infall rates are in agreement with the turbulent core model and those in other high-mass star-forming regions, suggesting that high accretion rate is a general requirement to form a massive star.