Sebastian Lipari

Extreme optical Fe II emission in luminous IRAS active galactic nuclei

Results of a program of studies and observations of strong optical Fe II emission in luminous and ultraluminous IRAS AGN are presented. New spectroscopic observations and studies of three known ultraluminous IRAS AGN with extreme optical Fe II emission, the discovery that PHL 1092 is a new ultraluminous IRAS AGN, and the detection of two new AGN with strongly variable flux in the optical Fe II emission lines are reported. These results are used to test the correlations between the Fe II emission and properties at other wavelengths such as the L(IR) and the radio emission. IR AGN with extreme Fe II emission are found to belong to a very important group of AGN, whose properties provide insight into the origin of the extreme Fe II emission and into the relation between the starburst and AGN phenomena.

Massive star formation and superwinds in IRAS 19254-7245 (the superantennae )

The ultraluminous IRAS galaxy IRAS 19254-7245 is investigated by means of aperture spectroscopy and images. It shows the spectral characteristics of a Seyfert 2-type galaxy with the emission lines split into four independent kinematical components separated by a velocity of 1491 km s −1 . A heavy internal obscuration corresponding to E(B-V)=1.40 and a total amount of ionized gas equal to M g =1.1×10 8 M ⊙ have been measured in the circumnuclear emission-line regions. The upper limit to the total dust mass is M d =1.5×10 7 M ⊙ and the corresponding cold gas mass is M cg =3.0×10 9 M ⊙ , while the total amount of molecular gas detected in the whole system is M H2 =3.0×10 10 M ⊙

Infrared mergers and infrared quasi-stellar objects with galactic winds – II. NGC 5514: two extranuclear starbursts with LINER properties and a supergiant bubble in the rupture phase

A study of the morphology, kinematics and ionization structure of the IR merger NGC5514, is here presented. This study is based mainly on INTEGRAL twodimensional (2D) spectroscopy (obtained at the 4.2 m William Herschel Telescope, WHT), plus optical and near IR images. Clear evidence of two extra-nuclear starbursts with young outflows (OFs) and LINER activity are reported. One of these OFs has generated a supergiant bubble and the other is associated with an extended complex of H ii region. In the galactic bubble it was found that: (i) the [S ii], H�, [N ii], [O i] and [O iii] emission line maps show a bubble with a distorted ellipsoidal shape, with major and minor axes of �6.5 kpc (13.

Infrared mergers and infrared quasi-stellar objects with galactic winds – III. Mrk 231: an exploding young quasi-stellar object with composite outflow/broad absorption lines (and multiple expanding superbubbles)

A study of outflow (OF) and BAL systems in Mrk 231 (and in similar IR QSOs) is presented. This study is based mainly on 1D and 2D spectroscopy (obtained at La Palma/WHT, HST, IUE, ESO/NTT, KPNO, APO and CASLEO observatories) plus HST images. For Mrk 231 we report evidence that the extreme nuclear OF process has at least 3 main components on different scales, which are probably associated with: (i) the radio jet, at pc scale; and (ii) the extreme starburst at pc and kpc scale. This OF has generated 4 or more concentric expanding bubbles and the BAL systems. Specifically, inside and very close to the nucleus the 2D spectra show the presence of an OF emission bump in the blend Hα+[N ii], with a peak at the same velocity of the main BAL–I system (VEjectionBAL−I ∼ –4700km s ). This bump was more clearly detected in the area located at 0. 6–1. 5 (490–1220 pc), to the south-west of the nucleus core, showing a strong and broad peak. In addition, in the same direction (at PA ∼60, i.e. close to the PA of the small scale radio jet) at 1. 7–2. 5, we also detected multiple narrow emission line components, with “greatly” enhanced [N ii]/Hα ratio (very similar to the spectra of jets bow shocks). These results suggest that the BAL–I system is generated in OF clouds associated with the parsec scale jet. The HST images show 4 (or 5) nuclear bubbles or shells with radius r ∼ 2.9, 1.5, 1.0, 0.6 and 0.2 kpc. For these bubbles, the 2D Hα velocity field (VF) map and 2D spectra show: (i) At the border of the more extended bubble (S1), a clear expansion of the shell with blueshifted velocities (with circular shape and at a radius r ∼ 5. 0). This bubble shows a rupture arc –to the south– suggesting that the bubble is in the blowout phase. The axis of this rupture or ejection (at PA ∼00) is coincident with the axis of the intermediate and large scale structures detected at radio wavelengths. (ii) In addition, in the 3 more external bubbles (S1, S2, S3), the 2D WHT spectra show multiple emission line components with OF velocities, of 〈VOFBubble〉 S1, S2 and S3 = [−(650−410)±30], [−500±30], and [−230±30]km s. (iii) In all the circumnuclear region (1. 8 < r < 5), the [N ii]/Hα and [S ii]/Hα narrow emission line ratios show high values (> 0.8), which are consistent with LINER/OF processes associated with fast velocity shocks. Therefore, we suggest that these giant bubbles are associated with the large scale nuclear OF component, which is generated –at least in part– by the extreme nuclear starburst: i.e., type II SN explosions. The variability of the short lived BAL–III Na ID system was studied, covering almost all the period in which this system appeared (between ∼1984–2004). We found that the BAL-III light curve (LC) is clearly asymmetric with: a steep increase, a clear maximum and an exponential fall (similar to the shape of a SN LC). The origin of this BAL-III system is discussed, mainly in the frame work of an extreme explosive event, probably associated with giant SNe/hypernova explosions. Finally, the IR colours diagram and the UV-BAL systems of IR+GW/OF+Fe ii QSOs are analysed. This study shows a new BAL IR QSO and suggest/confirm that these objects could be nearby young BAL QSOs, similar to those detected recently at z ∼ 6.0. We propose that the phase of young QSO is associated with: accretion of large amount of gas (by the SMBH) + extreme starbursts + extreme composite OFs/BALs. c

IR Mergers and IR QSOs with Galactic Winds. II. NGC 5514, two Extra-nuclear Starburts/LINERs with a Supergiant Bubble in the Rupture Phase

A study of the morphology, kinematics and ionization structure of the IR merger NGC5514, is here presented. This study is based mainly on INTEGRAL twodimensional (2D) spectroscopy (obtained at the 4.2 m William Herschel Telescope, WHT), plus optical and near IR images. Clear evidence of two extra-nuclear starbursts with young outflows (OFs) and LINER activity are reported. One of these OFs has generated a supergiant bubble and the other is associated with an extended complex of H ii region. In the galactic bubble it was found that: (i) the [S ii], H�, [N ii], [O i] and [O iii] emission line maps show a bubble with a distorted ellipsoidal shape, with major and minor axes of �6.5 kpc (13.

The nearest extreme starburst: bubbles, young star clusters and outflow in the merger NGC 3256

We have studied the extreme starburst in the infrared merger NGC 3256. We detect four galactic bubbles (using ESO New Technology Telescope and Hubble Space Telescope WFPC2 Hα images). These shells would be associated with previous supernova explosions. The first analysis of the spatial distribution of young star cluster candidates shows that more than 90 per cent of them are located in a complex starburst structure, including some of the bubble walls, three nuclei and three blue asymmetrical spiral arms. We have made a kinematic study of the ionized gas in the core of the main optical nucleus, performed with HST STIS spectra. The shape of the rotation curve and the emission-line profile can be explained by the presence in the core of young star clusters with outflow. Any low-luminosity active galactic nucleus associated with this core would have a mass less than 107 M⊙. It is also probable that the compact X-ray and radio emission of ULX(7)N – the source coincident with the main optical nucleus – is the result of a few recent supernova remnants.

LUMINOUS INFRARED GALAXIES. II. NGC 4945: A NEARBY OBSCURED STARBURST/SEYFERT NUCLEUS

We have studied the physical conditions, reddening, and kinematics in the nuclear and circumnuclear regions of the luminous IR source NGC 4945. The I-band image shows a wide cone of radiation that emerges from the partially obscured nuclear region. The Hα + [N II] image reveals an extended nuclear region located at the same position as the I-band nucleus. Two extended filaments emerge from this region as well. Aperture optical spectroscopy of the nuclear region shows strong reddening in the continuum, and only the blends Hα + [N II] and [S II] appear in emission. The long-slit spectroscopy at P.A. = 90°, coincident with the main Hα filament, shows in the nuclear region a weak [O I] LINER or weak [O III] Seyfert spectrum and blueshifted broad components in the [N II] and [S II] lines that are probably associated with superwinds. The velocity curve (at P.A. = 90°) is clearly asymmetric, with the mean velocity shifted toward the obscured nuclear region.

High-resolution study of luminous infrared galaxies. I: The composite nature of the Seyfert 1 galaxy IRAS 20044-6114 (NGC 6860)

The physical conditions in the ionized gas, the stellar population, and the kinematics of the Seyfert 1 galaxy IRAS 20044-6114 (NGC 6860) are studied by high spatial resolution optical imaging and optical and near-IR spectroscopy of this luminous IR source. The broadband images show a compact nucleus, two weak spiral arms, a bar, a bulge, an inner ring, and a possible outer ring. The I-alpha image reveals bright emission-line regions associated with the Seyfert nucleus and an inner ring of intense star formation. The forbidden O III 5007-A image shows that the high-excitation gas is elongated perpendicularly to the direction of the bar, and reveals a bright compact object at about 40 arcsec NE of the nucleus which is undetectable in the broadband images. This object is interpreted as a dwarf young H II galaxy. The optical, near-IR, and FIR results show clear evidence that the nuclear and circumnuclear regions have composite and complex structure: a variable Seyfert 1 nucleus embedded in an intense and dusty star formation. environment.

Diagnostics of Quasar Broad Absorption Line Geometry: X-Ray Observations and Two-dimensional Optical Spectroscopy

A new generation of sensitive X-ray measurements are indicating that the existence of X-ray attenuation column densities, NH > 1024 cm-2, is quite common among broad absorption line quasars (BALQSOs). This is significant to the geometry of the broad absorption line (BAL) outflow. In particular, such an X-ray shield also shields equatorial accretion disk winds from the UV, thereby preventing high-velocity equatorial outflows from being launched. By contrast, bipolar winds initiated by continuum radiation pressure from the funnel of a slim accretion disk flare outward (like a trumpet) and offer vastly different absorbing columns to the X-ray and UV emission that are emitted from distinct regions of the disk, ~6M and ~10M-40M, respectively (where M is the radius of the black hole). Recent numerical work indicates that it is also possible to launch bipolar outflows from the inner regions of a thin disk. The recent discovery with VLBI that the Galactic analog of a BALQSO, the X-ray binary Circinus X-1 (with high-velocity P Cygni X-ray absorption lines), is viewed virtually along the radio jet axis (and therefore along the spin axis of the black hole and the normal to the accretion disk) has rekindled interest in the bipolar models of BALQSOs. We explore this possibility by studying the nearest BALQSO, Mrk 231. High-resolution two-dimensional optical spectroscopy and VLBI mappings of the radio jet axis indicate that the BAL outflow is parallel to the parsec-scale radio jet.

IRAS 02366-3101 : an accretion disk candidate among luminous IRAS galaxies

In this Letter we present the detection, for the first time, of double-peaked broad Balmer Hα and Hβ emission-line profiles in a luminous IRAS galaxy : IRAS 02366-3101 with log L FIR =10.94 L ⊙ . This detection shows that IRAS 02366-3101 is a candidate to host an accretion disk around a supermassive black hole in its nucleus, although other alternatives cannot be ruled out