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arXiv · 1410.2558

Weak and Compact Radio Emission in Early Massive Star Formation Regions: An Ionized Jet Toward G11.11-0.12P1

V. Rosero·P. Hofner·M. McCoy·S. Kurtz·K. M. Menten·F. Wyrowski·E. D. Araya·L. Loinard·C. Carrasco-González·L. F. Rodríguez·R. Cesaroni·S. P. Ellingsen
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Abstract

We report 1.3 cm and 6 cm continuum observations toward the massive proto-stellar candidate G11.11-0.12P1 using the Karl G. Jansky Very Large Array (VLA). We detect a string of four unresolved radio continuum sources coincident with the mid-IR source in G11P1. The continuum sources have positive spectral indices consistent with a thermal (free-free) ionized jet. The most likely origin of the ionized gas are shocks due to the interaction of a stellar wind with the surrounding high-density material. We also present NIR United Kingdom Infrared Telescope (UKIRT) archival data which show an extended structure detected only at K-band (2.2 $\mu$m), which is oriented perpendicular to the jet, and that may be scattered light from a circumstellar disk around the massive protostar. Our observations plus the UKIRT archival data thus provide new evidence that a disk/jet system is present in the massive protostellar candidate located in the G11.11-0.12P1 core.

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V. Rosero, P. Hofner, M. McCoy, S. Kurtz, K. M. Menten, F. Wyrowski, E. D. Araya, L. Loinard, C. Carrasco-González, L. F. Rodríguez, R. Cesaroni, S. P. Ellingsen. 2014-10-09. Weak and Compact Radio Emission in Early Massive Star Formation Regions: An Ionized Jet Toward G11.11-0.12P1. https://doi.org/10.1088/0004-637x/796/2/130

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