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arXiv · 2103.05849

Assessing the stellar population and the environment of an HII region on the far side of the Galaxy

A. -N. Chené·R. A. Benjamin·S. Ramírez Alegría·J. Borissova·R. Kurtev·C. Moni Bidin·F. Mauro·P. Lucas·Z. Guo·L. C. Smith·C. Gonzalez-Fernandez·V. D. Ivanov·D. Minniti·L. D. Anderson·W. P. Armentrout·D. Gonzalez·A. Herrero·K. Peña Ramírez
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Abstract

We have investigated the stellar and interstellar content of the distant star formation region IRAS 17591-2228 (WISE HII region GAL 007.47+0.06). It is associated to a water maser, whose parallax distance is d=20.4^{+2.8} {-2.2} kpc, supported by independent measurements of proper motion and radial velocity. It is projected in the same direction as an extremely red (J-Ks ~ 6 mag) group of stars, and a shell of mid-infrared emission. We qualify the group of stars as a cluster candidate, VVV CL177. Its radius spans between 0.45' and 1' and contains at least two young stellar objects with an extreme extinction near Av ~ 40 mag. Yet more analysis will be required to determine is it is a real single cluster associated with the water maser. The 13CO emissions at the radial velocity of the maser corresponds to the mid-infrared emission.

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A. -N. Chené, R. A. Benjamin, S. Ramírez Alegría, J. Borissova, R. Kurtev, C. Moni Bidin, F. Mauro, P. Lucas, Z. Guo, L. C. Smith, C. Gonzalez-Fernandez, V. D. Ivanov, D. Minniti, L. D. Anderson, W. P. Armentrout, D. Gonzalez, A. Herrero, K. Peña Ramírez. 2021-03-10. Assessing the stellar population and the environment of an HII region on the far side of the Galaxy. https://doi.org/10.3847/1538-4357%2Fabec6f

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