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