HST / STIS Spectroscopy of 3 C
نویسنده
چکیده
We present preliminary results on the low-redshift Lyα forest as based on STIS spectra of 3C 273. A total of 121 intergalactic Lyα-absorbing systems were detected, of which 60 are above the 3.5σ com-pletness limit, logN HI ≈12.3. The median line-width parameter, b = 27 km/s, is similar to that seen at high redshift. However the distribution of HI column densities has a steeper slope, β = 2.02 ± 0.21, than is seen at high redshift. Overall, the observed N HI –b distribution is consistent with that derived from a ΛCDM hydrodynamic simulation.
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