Unshifted Metastable He I* Mini-Broad Absorption Line System in the Narrow Line Type 1 Quasar SDSS J080248.18++551328.9

We report the identification of an unusual absorption line system in the quasar SDSS J080248.18$+$551328.9 and present a detailed study of the system, incorporating follow-up optical and NIR spectroscopy. A few tens of absorption lines are detected, including He I*, Fe II* and Ni II* that arise from metastable or excited levels, as well as resonant lines in Mg I, Mg II, Fe II, Mn II, and Ca II. All of the isolated absorption lines show the same profile of width $\Delta v\sim 1,500$km s$^{-1}$ centered at a common redshift as that of the quasar emission lines, such as [O II], [S II], and hydrogen Paschen and Balmer series. With narrow Balmer lines, strong optical Fe II multiplets, and weak [O III] doublets, its emission line spectrum is typical for that of a narrow-line Seyfert 1 galaxy (NLS1). We have derived reliable measurements of the gas-phase column densities of the absorbing ions/levels. Photoionization modeling indicates that the absorber has a density of $n_{\rm H} \sim (1.0-2.5)\times 10^5~ {\rm cm}^{-3}$ and a column density of $N_{\rm H} \sim (1.0-3.2)\times 10^{21} \sim {\rm cm}^{-2}$, and is located at $R\sim100-250$ pc from the central super-massive black hole. The location of the absorber, the symmetric profile of the absorption lines, and the coincidence of the absorption and emission line centroid jointly suggest that the absorption gas is originated from the host galaxy and is plausibly accelerated by stellar processes, such as stellar winds \zhy{and/or} supernova explosions. The implications for the detection of such a peculiar absorption line system in an NLS1 are discussed in the context of co-evolution between super-massive black hole growth and host galaxy build-up.Comment: 28 pages, 16 figures; accepted for publication in Astrophysical Journa

Difference in Narrow Emission Line Spectra of Seyfert 1 and 2 galaxies

In the unification scheme of Seyfert galaxies, a dusty torus blocks the continuum source and broad line region in Seyfert 2 galaxies. However it is not clear whether or not and to what extent the torus affects the narrow line spectra. In this paper, we show that Seyfert 1 and Seyfert 2 galaxies have different distributions on the [OIII]/H$\beta$ vs [NII]/H$\alpha$ diagram (BPT diagram) for narrow lines. Seyfert 2 galaxies display a clear left boundary on the BPT diagram and only 7.3% of them lie on the left. By contrast, Seyfert 1 galaxies do not show such a cutoff and 33.0% of them stand on the left side of the boundary. Among Seyfert 1 galaxies, the distribution varies with the extinction to broad lines. As the extinction increases, the distribution on BPT diagram moves to larger [NII]/H$\alpha$ value. We interpret this as an evidence for the obscuration of inner dense narrow line region by the dusty torus. We also demonstrate that the [OIII] and broad line luminosity correlation depends on the extinction of broad lines in the way that high extinction objects have lower uncorrected [OIII] luminosities, suggesting that [OIII] is partially obscured in these objects. Therefore, using [OIII] as an indicator for the nuclear luminosity will systematically under-estimate the nuclear luminosity of Seyfert 2 galaxies.Comment: 12 pages, 2 figures, accepted for publication in ApJ Lette

Ensemble Learning Independent Component Analysis of Normal Galaxy Spectra

In this paper, we employe a new statistical analysis technique, Ensemble Learning for Independent Component Analysis (EL-ICA), on the synthetic galaxy spectra from a newly released high resolution evolutionary model by Bruzual & Charlot. We find that EL-ICA can sufficiently compress the synthetic galaxy spectral library to 6 non-negative Independent Components (ICs), which are good templates to model huge amount of normal galaxy spectra, such as the galaxy spectra in the Sloan Digital Sky Survey (SDSS). Important spectral parameters, such as starlight reddening, stellar velocity dispersion, stellar mass and star formation histories, can be given simultaneously by the fit. Extensive tests show that the fit and the derived parameters are reliable for galaxy spectra with the typical quality of the SDSS.Comment: 41 pages, 23 figures, to be published in A

Metal-Enriched Outflows in the Ultra-Luminous infrared Quasar Q1321+058

Quasar outflows may play important role in the evolution of its host galaxy and central black hole. In this paper, we present a detailed study of multiple outflows in the obscured ultra-luminous infrared quasar Q1321+058. The outflows reveal themselves in the complex optical and UV emission line spectrum, with a broad component blueshifted by 1650 km/s and a narrow component by 360 km/s, respectively.The higher velocity component shows ever strong N III] and strong Si III], in addition to strong [O III]5007 and [Ne III]3869 emission lines, suggesting an overabundance of N and Si relative to C. The abundance pattern is consistent a fast chemical enriching process associated with a recent starburst. The outflow extends to several tens to hundred parsecs from the quasar, and covers only a very small sky. We find that the outflow with line emitting gas is energetically insufficient to remove the ISM of the host galaxy. The velocity range and the column density suggest that the outflow might be part of the low ionization broad absorption line region as seen in a small class of quasars. The optical and UV continuum is starlight-dominated and can be modelled with a young-aged (1 Myr) plus an intermediate-aged (~0.5-1 Gyr) stellar populations, suggesting a fast building of the stellar mass in the host galaxy, consistent with the starburst-type metal abundances inferred from the high velocity outflow spectrum. The broad band spectral energy distribution shows that it is an obscured quasar with its bulk emission in the middle infrared. The star formation rate, independently estimated from UV, far-infrared, and emission line luminosity, is much lower than that is required for the co-evolution of the black hole and its host spheroid.Comment: 31 pages, accepted to Ap