The complications of learning from Super Soft Source X-ray spectra

Jan-Uwe Ness

doi:10.1016/j.asr.2019.09.002

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arXiv · 1909.09711

The complications of learning from Super Soft Source X-ray spectra

Jan-Uwe Ness

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Abstract

Super Soft X-ray Sources (SSS) are powered by nuclear burning on the surface of an accreting white dwarf, they are seen around 0.1-1 keV (thus in the soft X-ray regime), depending on effective temperature and the amount of intervening interstellar neutral hydrogen N_H. The most realistic model to derive physical parameters from observed SSS spectra would be an atmosphere model that simulates the radiation transport processes. However, observed SSS high-resolution grating spectra reveal highly complex details that cast doubts on the feasibility of achieving unique results from atmosphere modeling. In this article, I discuss two independent atmosphere model analyses of the same data set, leading to different results. I then show some of the details that complicate the analysis and conclude that we need to approach the interpretation of high-resolution SSS spectra differently. We need to focus more on the data than the models and to use more phenomenological approaches as is traditionally done with optical spectra.

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Jan-Uwe Ness. 2019-09-20. The complications of learning from Super Soft Source X-ray spectra. https://doi.org/10.1016/j.asr.2019.09.002

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