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The Metallicity of the Redshift 4.16 Quasar BR2248-1242

Craig Warner·Fred Hamann·Joseph C. Shields·Anca Constantin·Craig B. Foltz·Frederic H. Chaffee
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Abstract

We estimate the metallicity in the broad emission-line region of the redshift z=4.16 quasar, BR2248-1242, by comparing line ratios involving nitrogen to theoretical predictions. BR2248-1242 has unusually narrow emission lines with large equivalent widths, thus providing a rare opportunity to measure several line-ratio abundance diagnostics. The combined diagnostics indicate a metallicity of ~2 times solar. This result suggests that an episode of vigorous star formation occurred near BR2248-1242 prior to the observed z=4.16 epoch. The time available for this enrichment episode is only ~1.5 Gyr at z=4.16 (for H_{0}=65 km s^-1 Mpc^-1, Omega_{m}=0.3 and Omega_Lambda ~< 1). This evidence for high metallicities and rapid star formation is consistent with the expected early-epoch evolution of dense galactic nuclei.

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Craig Warner, Fred Hamann, Joseph C. Shields, Anca Constantin, Craig B. Foltz, Frederic H. Chaffee. 2001-11-05. The Metallicity of the Redshift 4.16 Quasar BR2248-1242. https://doi.org/10.1086/338575

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