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arXiv · 1011.5042

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

K. L. J. Rygl·A. Brunthaler·K. M. Menten·M. J. Reid·H. J. van Langevelde·M. Honma·K. J. E. Torstensson·K. Fujisawa·A. Sanna
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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).

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K. L. J. Rygl, A. Brunthaler, K. M. Menten, M. J. Reid, H. J. van Langevelde, M. Honma, K. J. E. Torstensson, K. Fujisawa, A. Sanna. 2010-12-02. A preliminary distance to W 75N in the Cygnus X star-forming region. https://arxiv.org/abs/1011.5042

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