This paper summarizes the largest survey to date (Danforth andShull 2008) of the intergalactic medium (IGM) at low redshift, utilizing data fromthe Far Ultraviolet Spectroscopic Explorer and Hubble Space Telescope satellites.The IGM was detected in absorption against background AGN at z < 0.4. Thesurvey identifies 650 Lyα and 83 O VI absorbers. O VI has a steeper power slopethan H I (dN/dz ∝N_~(-β),β_(O VI) ～ 2,β_(H I) = 1.7). Approximately 40% of baryonsat low redshift are accounted for in the IGM (30% in the Lyα forest, 10% in thewarm-hot IGM). O VI 1032-38 A and N V 1238-42 A absorbers are reliable WHIMtracers and are inconsistent with photoionization. The O VI transition is currentlya much better WHIM tracer (N ～100) than X-ray O VII and O VIII detections (N～ 1-2). The O VI detection frequency (dN/dz) implies metal transport out to 250-300 kpc from dwarf galaxies (L = 0.03 L~*).
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机译：本文利用远紫外光谱浏览器和哈勃太空望远镜卫星的数据总结了迄今为止在低红移下银河系中间介质（IGM）的最大调查（Danforth and Shull 2008），在z <0.4的背景AGN吸收下检测到IGM。 。调查确定了650个Lyα和83个O VI吸收剂。 O VI的功率斜率比H I陡（dN / dz ∝N_〜（-β），β_（O VI）〜2，β_（H I）= 1.7）。 IGM中约有40％的重子低红移发生在IGM中（Lyα森林中为30％，热IGM中为10％）。 O VI 1032-38 A和N V 1238-42 A吸收剂是可靠的WHIM示踪剂，与光电离不一致。 O X跃迁目前是WHIM示踪剂（N〜100）比X射线O VII和O VIII检测（N〜1-2）好得多。 O VI的检测频率（dN / dz）意味着金属从矮星系（L = 0.03 L〜*）传输到250-300 kpc。
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