Properties of a Chemically Enriched Ly α Absorption System at z = 0 . 167 and Implications for the Total Baryons
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چکیده
We present a detailed analysis of the chemical abundances, ionization state, and origin of a partial Lyman limit system (N(H I) ≈ 10 cm) at low redshift (z = 0.167 towards PKS0405−1219). We also present the first estimate of the total baryons in extended gaseous envelopes around galaxies based on a simple photoionization model for the Lyα absorbers. We find that extended gaseous envelopes can explain between 5–20% of the total baryons predicted by the big bang nucleosynthesis model.
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تاریخ انتشار 2001