# Millimeter and far-IR study of the IRCD SDC 341.232-0.268

## TL;DR

This study investigates the molecular gas and dust in the IRDC SDC 341.232-0.268 using millimeter and far-IR data to understand its physical properties, evolutionary stage, and gas dynamics such as infall and outflow motions.

## Contribution

It combines multi-wavelength observations and molecular line analysis to characterize the physical conditions and gas motions in an infrared dark cloud for the first time.

## Key findings

- Identified two dense clumps with >10^4 cm^-3 density.
- Detected infall and outflow motions in the molecular gas.
- Found cold dust associated with the molecular clumps and EGOs.

## Abstract

We analyze the molecular gas and dust associated with the infrared dark cloud SDC 341.232-0.268 in order to investigate the characteristics and parameters of the gas, determine the evolutionary status of four embedded EGO candidates and establish possible infall or outflow gas motions. We based our study on $^{12}$CO(2-1), $^{13}$CO(2-1), and C$^{18}$O(2-1) data obtained with the APEX telescope, molecular data of high density tracers from the MALT90 survey and IR images from Spitzer, Herschel and ATLASGAL. The study reveals two clumps at -44 km/s towards the IRDC, with densities of > 10$^4$ cm$^{-3}$ , typical of IRDCs, while high density tracers show H$_2$ densities > 10$^5$ . FIR images reveals the presence of cold dust linked to the molecular clumps and EGOs. A comparison of spectra of the optically thin and optically thick molecular lines towards the EGOs suggests the existence of infall and outflow motions.