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arXiv · astro-ph/0408262

The LyB and OVI Forest in the Local Universe

Charles W. Danforth·J. Michael Shull
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Abstract

Intergalactic absorbers along lines of sight to distant quasars are a powerful diagnostic for the evolution and content of the IGM. In this study, we search known low-z Ly-alpha absorption systems for equivalent absorption in higher Lyman lines as well as the important metal ions OVI and CIII. OVI absorption is detected roughly half the time and shows a smaller range of column density than HI. This implies a multi-phase IGM with warm neutral and hot ionized components. We use our OVI detection statistics to determine that the fraction of intergalalctic mass at 10^5-10^6 K is at least 5% of the total baryonic mass in the local (z<0.15) universe.

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Charles W. Danforth, J. Michael Shull. 2004-08-13. The LyB and OVI Forest in the Local Universe. https://arxiv.org/abs/astro-ph/0408262

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