Ly α Cloud Size Evolution and Shape from QSO Groups
نویسنده
چکیده
We present results from Keck HIRES, KPNO 4m/RC Spec and HST FOS spectra of a low-redshift, close QSO pair and a close, higher-redshift QSO triplet in order to explore the size evolution, shape and clustering of Ly α absorbers. The results we highlight here indicate that there is no strong evidence for evolution of Ly α cloud size with redshift, that strong (Wo > 0.4Å) Ly α forest absorbers are probably not filaments, but probably more sheet-like. For C IV absorbers a large component of clustering on 200 km s < ∆v < 600 km s scales along single sightlines is due to internal velocities of single absorbers, not clustering between absorbers.
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