Detailed X-ray line properties of θ² Ori A in quiescence

  title={Detailed X-ray line properties of $\theta$² Ori A in quiescence},
  author={Arik W. Mitschang and Norbert S. Schulz and David P. Huenemoerder and Joy S. Nichols and Paola Testa Smithsonian Astrophysical Observatory Mit Ka Astrophysics and Space Research},
  journal={The Astrophysical Journal},
We investigate X-ray emission properties of the peculiar X-ray source θ2 Ori A in the Orion Trapezium region using more than 500 ks of HETGS spectral data in the quiescent state. The amount of exposure provides tight constraints on several important diagnostics involving O, Ne, Mg, and Si line flux ratios from He-like ion triplets, resonance line ratios of the H- and He-like lines, and line widths. Accounting for the influence of the strong UV radiation field of the O9.5V star, we can now place… 

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