A preliminary distance to W 75N in the Cygnus X star-forming region

TL;DR

This study measures the distance to W75N in Cygnus X using VLBI parallax observations, providing a more accurate estimate that suggests it is closer than previously thought, which impacts understanding of the region's structure.

Contribution

The paper presents the first precise parallax measurement of W75N in Cygnus X, clarifying its distance and contributing to resolving the long-standing uncertainty about the region's structure.

Findings

W75N is at a distance of approximately 1.32 kpc.

The measured distance is closer than previous estimates of 1.5-2 kpc.

Results help clarify the structure of the Cygnus X star-forming region.

Abstract

Cygnus X is one of the closest giant molecular cloud complexes and therefore an extensively studied region of ongoing high mass star formation. However, the distance to this region has been a long-standing issue, since sources at galactic longitude of ~80 degrees could be in the Local Arm nearby (1-2 kpc), in the Perseus Arm at ~5 kpc, or even in the outer arm (~10 kpc). We use combined observations of the EVN plus two Japanese stations to measure very accurate parallaxes of methanol masers in five star-forming regions in Cygnus X to understand if they belong to one large star-forming complex or if they are separate entities located at different distances. Here we report our preliminary result for W75N based on six epochs of VLBI observations: we find that W75N is at a distance of 1.32^{+0.11}_{-0.09} kpc, which is significantly closer than the reported values in the literature (1.5-2 kpc).