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Chandra HETGS Multi-Phase Spectroscopy of the Young Magnetic O Star theta^1 Orionis C

Marc Gagne·Mary E. Oksala·David H. Cohen·Stephanie K. Tonnesen·Asif ud-Doula·Stanley P. Owocki·Richard H. D. Townsend·Joseph J. MacFarlane
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Abstract

We report on four Chandra grating observations of the oblique magnetic rotator theta^1 Ori C (O5.5 V) covering a wide range of viewing angles with respect to the star's 1060 G dipole magnetic field. We employ line-width and centroid analyses to study the dynamics of the X-ray emitting plasma in the circumstellar environment, as well as line-ratio diagnostics to constrain the spatial location, and global spectral modeling to constrain the temperature distribution and abundances of the very hot plasma. We investigate these diagnostics as a function of viewing angle and analyze them in conjunction with new MHD simulations of the magnetically channeled wind shock mechanism on theta^1 Ori C. This model fits all the data surprisingly well, predicting the temperature, luminosity, and occultation of the X-ray emitting plasma with rotation phase.

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Marc Gagne, Mary E. Oksala, David H. Cohen, Stephanie K. Tonnesen, Asif ud-Doula, Stanley P. Owocki, Richard H. D. Townsend, Joseph J. MacFarlane. 2005-06-06. Chandra HETGS Multi-Phase Spectroscopy of the Young Magnetic O Star theta^1 Orionis C. https://doi.org/10.1086/430873

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