Super-solar Metallicity in the NLS1 Galaxy Markarian 1044

The determination of the bulk metallicity and the abundance mixture of various elements is very difficult in quasars and AGNs because only a few lines are observed and the ionization correction is unknown. Most abundance studies of AGNs assume the N/C ratio scales as metallicity (nitrogen goes as metallicity squared) and so serves as a metallicity indicator. We present an accurate metallicity determination of the narrow-line Seyfert 1 (NLS1) galaxy Markarian 1044, using O VI column density measurements from the Far Ultraviolet Spectroscopic Explorer (FUSE) together with C IV, N V, and H I from Hubble Space Telescope (HST) observations. In this absorption line study we find that the circumnuclear gas in Mrk 1044 has a metallicity of at least five times solar. This is consistent with the expectation that NLS1s have a high metallicity, similar to that found in high-redshift quasars. More surprisingly, we find that the absorbing material requires a near-solar mixture. In other words, the N/C is consistent with the solar ratio, and does not scale with the metallicity. This suggests that the chemical enrichment scenario for this object, and perhaps for AGNs in general, may be different from the traditional model of galactic metal enrichment, at least in the high-metallicity regime.