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arXiv · 0809.3495

Suzaku and XMM-Newton Observations of Diffuse X-ray Emission from the Eastern Tip Region of the Carina Nebula

Yuichiro Ezoe·Kenji Hamaguchi·Robert A. Gruendl·You-Hua Chu·Robert Petre·Michael F. Corcoran
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Abstract

The eastern tip region of the Carina Nebula was observed with the Suzaku XIS for 77 ks to conduct a high-precision spectral study of extended X-ray emission. XMM-Newton EPIC data of this region were also utilized to detect point sources. The XIS detected strong extended X-ray emission from the entire field-of-view with a 0.2--5 keV flux of $0.7\sim4\times10^{-14}$ erg s$^{-1}$ arcmin$^{-2}$. The emission has a blob-like structure that coincides with an ionized gas filament observed in mid-infrared images. Contributions of astrophysical backgrounds and the detected point sources were insignificant. Thus the emission is diffuse in nature. The X-ray spectrum of the diffuse emission was represented by a two-temperature plasma model with temperatures of 0.3 and 0.6 keV and an absorption column density of 2$\times10^{21}$ cm$^{-1}$. The X-ray emission showed normal nitrogen-to-oxygen abundance ratios and a high iron-to-oxygen abundance ratio. The spectrally deduced parameters, such as temperatures and column densities, are common to the diffuse X-ray emission near $η$ Car. Thus, the diffuse X-ray emission in these two fields may have the same origin. The spectral fitting results are discussed to constrain the origin in the context of stellar winds and supernovae.

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Yuichiro Ezoe, Kenji Hamaguchi, Robert A. Gruendl, You-Hua Chu, Robert Petre, Michael F. Corcoran. 2008-09-20. Suzaku and XMM-Newton Observations of Diffuse X-ray Emission from the Eastern Tip Region of the Carina Nebula. https://arxiv.org/abs/0809.3495

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