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arXiv · 1206.0863

[S IV] in the NGC 5253 Supernebula: Ionized Gas Kinematics at High Resolution

Sara C. Beck·John H. Lacy·Jean L. Turner·Andrew Kruger·Matt Richter·Lucian P. Crosthwaite
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Abstract

The nearby dwarf starburst galaxy NGC 5253 hosts a deeply embedded radio-infrared supernebula excited by thousands of O stars. We have observed this source in the 10.5{\mu}m line of S+3 at 3.8 kms-1 spectral and 1.4" spatial resolution, using the high resolution spectrometer TEXES on the IRTF. The line profile cannot be fit well by a single Gaussian. The best simple fit describes the gas with two Gaussians, one near the galactic velocity with FWHM 33.6 km s-1 and another of similiar strength and FWHM 94 km s-1 centered \sim20 km s-1 to the blue. This suggests a model for the supernebula in which gas flows towards us out of the molecular cloud, as in a "blister" or "champagne flow" or in the HII regions modelled by Zhu (2006).

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Sara C. Beck, John H. Lacy, Jean L. Turner, Andrew Kruger, Matt Richter, Lucian P. Crosthwaite. 2012-06-05. [S IV] in the NGC 5253 Supernebula: Ionized Gas Kinematics at High Resolution. https://doi.org/10.1088/0004-637x/755/1/59

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