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HST/STIS Spectroscopy of 3C 273

S. R. Heap·G. M. Williger·R. Dave·R. J. Weymann·E. B. Jenkins·T. M. Tripp
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Abstract

We present preliminary results on the low-redshift Lyman alpha forest as based on STIS spectra of 3C 273. A total of 121 intergalactic Lyman alpha-absorbing systems were detected, of which 60 are above the 3.5 sigma completness limit, log N(HI)~12.3. The median Doppler parameter, b=27 km/s, is similar to that seen at high redshift. However the distribution of HI column densities (dN/dN(HI) propto N(HI)^-beta) has a steeper slope, beta = 2.02 +- 0.21, than is seen at high redshift. Overall, the observed N(HI)-b distribution is consistent with that derived from a Lambda CDM hydrodynamic simulation.

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S. R. Heap, G. M. Williger, R. Dave, R. J. Weymann, E. B. Jenkins, T. M. Tripp. 2001-09-06. HST/STIS Spectroscopy of 3C 273. https://arxiv.org/abs/astro-ph/0109100

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