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arXiv · 1711.01794

The Green Bank Ammonia Survey: Unveiling the Dynamics of the Barnard 59 star-forming Clump

Abstract

Understanding the early stages of star formation is a research field of ongoing development, both theoretically and observationally. In this context, molecular data have been continuously providing observational constraints on the gas dynamics at different excitation conditions and depths in the sources. We have investigated the Barnard 59 core, the only active site of star formation in the Pipe Nebula, to achieve a comprehensive view of the kinematic properties of the source. These information were derived by simultaneously fitting ammonia inversion transition lines (1,1) and (2,2). Our analysis unveils the imprint of protostellar feedback, such as increasing line widths, temperature and turbulent motions in our molecular data. Combined with complementary observations of dust thermal emission, we estimate that the core is gravitationally bound following a virial analysis. If the core is not contracting, another source of internal pressure, most likely the magnetic field, is supporting it against gravitational collapse and limits its star formation efficiency.

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E. Redaelli, F. O. Alves, P. Caselli, J. E. Pineda, R. K. Friesen, A. Chacón-Tanarro, C. D. Matzner, A. Ginsburg, E. Rosolowsky, J. Keown, S. S. R. Offner, J. Di Francesco, H. Kirk, P. C. Myers, A. Hacar, A. Cimatti, H. H. Chen, M. C. Chen, Y. M. Seo, K. I. Lee. 2017-11-06. The Green Bank Ammonia Survey: Unveiling the Dynamics of the Barnard 59 star-forming Clump. https://doi.org/10.3847/1538-4357%2Faa9703

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