S. Komossa et S. Mathur, Supersolar metal abundances and the broad line region of narrow-line seyfert 1 galaxies, ASTRON ASTR, 374(3), 2001, pp. 914-918
Narrow-line Seyfert 1 galaxies (NLSy1) are intriguing due to their extreme
continuum and emission line properties which are not yet well understood. T
his paper is motivated by the recent suggestion that NLSy1 galaxies might b
e young active galactic nuclei (AGNs) and that they may have supersolar met
al abundances. We have examined the stability of broad emission line region
(BLR) clouds under isobaric perturbation and its dependence on gas metal a
bundances. We show that supersolar metallicity increases the range where mu
ltiple phases in pressure balance may exist. This is particularly important
for NLSy1s with steep X-ray spectra where it delays the trend of hindrance
of a multi-phase equilibrium. Finally, the role of warm absorbers in the c
ontext of this scenario is assessed.