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We study the kinematic properties of the ionised gas outflows and ambient interstellar medium (ISM) in a large and representative sample of local luminous and ultra-luminous infrared galaxies (U/LIRGs) (58 systems, 75 galaxies) at galactic and sub-galactic (i.e., star-forming clumps) scales, thanks to integral field spectroscopy (IFS)-based high signal-to-noise integrated spectra. The velocity dispersion of the ionized ISM in U/LIRGs (〈σ〉 ~ 70 km s-1) is larger than in lower luminosity local star-forming galaxies (〈σ〉 ~ 25 km s-1). While for isolated disc LIRGs star formation appears to sustain turbulence, gravitational energy release associated with interactions and mergers plays an important role in driving σ in the U/LIRG range. We find that σ has a dependency on the star formation rate density (ΣSFR), which is weaker than expected if it were driven by the energy released by the starburst. The relatively small role of star formation (SF) driving the σ in U/LIRGs is reinforced by the lack of an increase in σ associated with high luminosity SF clumps. We also find that the impact of an active galactic nucleus (AGN) in ULIRGs is strong, increasing on average σ by a factor 1.5. Low-z U/LIRGs cover a range of velocity dispersion (σ ~ 30 to 100 km s-1) and star formation rate density (ΣSFR ~ 0.1 to 20 M⊙ yr-1 kpc-2) similar to those of high-z SFGs. Moreover, the observed weak dependency of σ on ΣSFR for local U/LIRGs (σ ∝ ΣSFR +0.06) is in very good agreement with that measured in some high-z samples. The presence of ionized gas outflows in U/LIRGs seems universal based on the detection of a broad, usually blueshifted, Hα line. The observed dependency of the maximum velocity of the outflow (Vmax) on the star formation rate (SFR) is of the type Vmax(non - AGN) ∝ SFR(LIR)+ 0.24. We find that AGNs in U/LIRGs are able to generate faster (~×2) and more massive (~× 1.4) ionized gas outflows than pure starbursts. The derived ionized mass loading factors (η) are in general below 1, with only a few AGNs above this limit. The escaping gas fraction is low with only less massive (log(M dyn/M⊙) < 10.4) U/LIRGs having outflowing terminal velocities higher than their escape velocities, and more massive galaxies retaining the gas, even if they host an AGN. The observed average outflow properties in U/LIRGs are similar to high-z galaxies of comparable SFR. However, while high-z galaxies seem to require ΣSFR > 1 M ⊙ yr-1 kpc-2 for launching strong outflows, this threshold is not observed in low-z U/LIRGs even after correcting for the differential fraction of the gas content. In the bright SF clumps found in LIRGs, ionized gas outflows appear to be very common (detection rate over 80%). Their observed properties are less extreme than those associated with the entire galaxy. The clumps in LIRGs follow the general size-L-σ scaling relations found for low- and high-z clumps, though they are in general smaller, less luminous, and are characterized by lower σ than at high-z. For a given observed (no internal extinction correction applied) star formation surface density, outflows in LIRG clumps would be about one to two orders of magnitude less energetic than the outflows launched by clumps in high-z SF galaxies., This work has been supported by the Spanish Ministry of Science and Innovation (MICINN) under grants ESP2007-65475-C02-01, AYA2010-21161-C02-01, AYA2012-32295, AYA2012-39408-C02-C01,and by the Marie Curie Initial Training Network ELIXIR of the European Commission under contract PITN-GA-2008-214227.

We present the results of high resolution mapping of the CO(1-0) and CO(2-1) emission of the ultraluminous infrared galaxy (ULIRG) IRAS 10190+1322, with the IRAM interferometer, down to an angular resolution of ~0.3 arcsec. This object is composed of two interacting galaxies with a projected nuclear separation of 6 kpc, and was selected to analyze the physical and dynamical properties of the molecular gas in each galaxy in order to study the conditions that lead a galaxy pair to become ultraluminous in the infrared. With the exception of Arp 220, the closest ULIRG, this is the first time that the CO emission is morphologically and kinematically resolved in the two interacting galaxies of a ULIRG system. In one of the galaxies the molecular gas is highly concentrated, distributed in a circumnuclear disk of 1.7 kpc in size. The molecular gas in the presumably less infrared luminous galaxy is distributed in a more extended disk of 7.4 kpc. The molecular gas mass accounts for ~10% of the dynamical mass in each galaxy. Both objects are rich enough in molecular gas, Mgas ~ 4 10^9 Msun, as to experience an infrared ultraluminous phase., 4 pages, 3 figures. Accepted for publication in A&A Letters Special Issue for the new extended configuration of the Plateau de Bure Interferometer

LINERs are found in ~30% of all bright galaxies, including luminous infrared galaxies. They form a heterogeneous class powered by a variety of ionizing mechanisms such as low-luminosity AGNs, starbursts, shocks, or any combination of these.In early-type spirals, LINERs are powered by a low-luminosity AGN, or by an AGN surrounded by circumnuclear star-forming regions. In luminous infrared galaxies, LINERs are powered by starbursts with associated wind-related extended shocks, and an AGN may play a minor role, if any. LINERs in some FR I radio galaxies show a strong evidence for the presence of a massive central black hole, and there are indications for the existence of shocks in the nuclear disks of these galaxies. Yet, the dominant ionizing mechanism for LINERs in radio-quiet ellipticals and FR I host galaxies is still unclear.Multifrequency high spatial resolution imaging and spectroscopy are essential to discriminate among the different ionizing mechanisms present in LINERs.

22 pages, 4 figures.-- ArXiv pre-print available at: http://arxiv.org/abs/astro-ph/0606186, We use Hubble Space Telescope (HST) NICMOS continuum and Paα observations to study the near-infrared and star formation properties of a representative sample of 30 local (d ~ 35-75 Mpc) luminous infrared galaxies (LIRGs, infrared [8-1000 μm] luminosities of log LIR = 11-11.9 Lsun). The data provide spatial resolutions of 25-50 pc and cover the central ~3.3-7.1 kpc regions of these galaxies. About half of the LIRGs show compact (~1-2 kpc) Paα emission with a high surface brightness in the form of nuclear emission, rings, and minispirals. The rest of the sample show Paα emission along the disk and the spiral arms extending over scales of 3-7 kpc and larger. About half of the sample contains H II regions with Hα luminosities significantly higher than those observed in normal galaxies. There is a linear empirical relationship between the mid-IR 24 μm and hydrogen recombination (extinction-corrected Paα) luminosity for these LIRGs, and the H II regions in the central part of M51. This relation holds over more than four decades in luminosity, suggesting that the mid-IR emission is a good tracer of the star formation rate (SFR). Analogous to the widely used relation between the SFR and total IR luminosity of R. Kennicutt, we derive an empirical calibration of the SFR in terms of the monochromatic 24 μm luminosity that can be used for luminous, dusty galaxies., AAH and LC acknowledge support from the Spanish Programa Nacional de Astronomía y Astrofísica under grant AYA2002-01055 and Plan Nacional del Espacio ESP2005-01480, and PGPG from the Spanish Programa Nacional de Astronomía y Astrofísica under grant AYA 2004-01676. This work has been funded by NASA grant HST-GO-10169 and by NASA through contract 1255094 issued by JPL/Caltech.

Based on observations carried out with ALMA in Cycle 0.-- et al., [Aims]: We investigate the fueling and the feedback of star formation and nuclear activity in NGC 1068, a nearby (D = 14 Mpc) Seyfert 2 barred galaxy, by analyzing the distribution and kinematics of the molecular gas in the disk. We aim to understand if and how gas accretion can self-regulate. [Methods]: We have used the Atacama Large Millimeter Array (ALMA) to map the emission of a set of dense molecular gas (n(H2) ' 1056 cm3) tracers (CO(3-2), CO(6-5), HCN(4-3), HCO+(4-3), and CS(7-6)) and their underlying continuum emission in the central r ∼ 2 kpc of NGC 1068 with spatial resolutions ∼0:3000:500 (∼20-35 pc for the assumed distance of D = 14 Mpc). [Results]: The sensitivity and spatial resolution of ALMA give an unprecedented detailed view of the distribution and kinematics of the dense molecular gas (n(H2) ≈ 1056cm3) in NGC 1068. Molecular line and dust continuum emissions are detected from a r ∼ 200 pc off-centered circumnuclear disk (CND), from the 2.6 kpc-diameter bar region, and from the r ∼ 1:3 kpc starburst (SB) ring. Most of the emission in HCO+, HCN, and CS stems from the CND. Molecular line ratios show dramatic order-of-magnitude changes inside the CND that are correlated with the UV/X-ray illumination by the active galactic nucleus (AGN), betraying ongoing feedback. We used the dust continuum fluxes measured by ALMA together with NIR/MIR data to constrain the properties of the putative torus using CLUMPY models and found a torus radius of 20+6 10 pc. The Fourier decomposition of the gas velocity field indicates that rotation is perturbed by an inward radial flow in the SB ring and the bar region. However, the gas kinematics from r ∼ 50 pc out to r ∼ 400 pc reveal a massive (Mmol ∼ 2:7+0:9 1:2 × 107 M) outflow in all molecular tracers. The tight correlation between the ionized gas outflow, the radio jet, and the occurrence of outward motions in the disk suggests that the outflow is AGN driven. [Conclusions]: The molecular outflow is likely launched when the ionization cone of the narrow line region sweeps the nuclear disk. The outflow rate estimated in the CND, dM=dt ∼ 63+21 37 M yr1, is an order of magnitude higher than the star formation rate at these radii, confirming that the outflow is AGN driven. The power of the AGN is able to account for the estimated momentum and kinetic luminosity of the outflow. The CND mass load rate of the CND outflow implies a very short gas depletion timescale of ≤1 Myr. The CND gas reservoir is likely replenished on longer timescales by efficient gas inflow from the outer disk. © ESO 2014., S.G.B. and I.M. acknowledge support from Spanish grants AYA2010-15169 and from the Junta de Andalucia through TIC-114 and the Excellence Project P08-TIC-03531. S.G.B., A.L., and A.F. acknowledge support from MICIN within program CONSOLIDER INGENIO 2010, under grant “Molecular Astrophysics: The Herschel and ALMA Era–ASTROMOL” (ref CSD2009-00038). S.G.B., A.U., L.C., and P.P. acknowledge support from Spanish grant AYA2012-32295. FC acknowledges the European Research Council for the Advanced Grant Program Num. 267399-Momentum. A.A.H. acknowledges support from the Universidad de Cantabria through the Augusto G. Linares programme and from the Spanish Plan Nacional grants AYA2009-05705-E and AYA2012-31447. C.R.A. is supported by a Marie Curie Intra European Fellowship within the 7th European Community Framework Programme (PIEF-GA-2012-327934). C.R.A. also ackowledges financial support from the Spanish Ministry of Science and Innovation (MICINN) through project PN AYA2010-21887-C04.04 (Estallidos).

We have started an observational program to cover a representative sample of radio galaxies containing radio jets in order to study the optical properties of the parent galaxy, their relationship to the radio properties as well as to detect optical emission associated with the radio structures.

Sensitive high spatial resolution optical and infrared imaging and optical spectroscopy are presented for the active galaxy IC 5063. Physical and kinematic conditions are derived for the emission regions, and deep images of the dust and optical line emission are presented. These support the proposition that the gas and dust arise from a recent merger event. Strong evidence is found for the presence of a hidden, luminous ionization source in the nucleus of IC 5063. This comprises the detection of a broad faint H-alpha emission line with FWZI roughly 6000 km/s, the detection of high-excitation forbidden Fe VII emission lines and the presence of an extended emission-line region with a well-defined region of high excitation. One of the best examples of a highly anisotropic ionizing radiation field is found, with the high-excitation line emission displaying a distinctive X or conical morphology. This cone has a 50 deg opening angle in projection, extends over 22 kpc and has a large-scale X-type morphology, very probably due to dust obscuration of the ionization beam. This is in turn consistent with consideration of the energetic balance between the ionized gas and infrared emission. 69 refs.

CCD photometry of the jet in the Thuan-Gunn r and g filters obtained under good seeing conditions is presented. Elliptical models of the underlying stellar emission were subtracted from the reduced and calibrated images. The high signal to noise ratio and good spatial resolution make it possible to determine very accurately the morphological properties of the jet. These observations reveal a number of new features: the outermost knot (H) can be resolved into several components, and the spectral index of the knots between the r and g bands is in general steeper than in that in the radio and shows a trend to become steeper with distance from the nucleus. The implications of these results for current radiation jet models will be briefly discussed.

We present preliminary results of a CCD survey of nearby (z

The behavior of the C IV 1550 A emission line strength in variable active galactic nuclei (AGNs) such as Seyfert 1 galaxies and one broad-line radio galaxy (BLRG) is discussed on the basis of low-resolution spectra from IUE. The results are compared with those obtained previously for QSO samples. The variation of individual AGNs indicate that they present matter-bounded conditions when the AGN is in a high-luminosity state. Such behavior is illustrated by the variations seen in the Seyfert 1 galaxy F9, where the transition from photon-bounded to matter-bounded occurs at a transition luminosity of ergs/sec per Hz. The results indicate the existence of a transition luminosity, which appears to be typical for an individual galaxy. An absolute luminosity limit also appears to be present both in the C IV line at 45.0 ergs/sec and for the continuum at 31.7 ergs/sec per Hz. 25 references.

CCD photometry of the M87 jet in the Thuan-Gunn r and g filters is presented. Accurate elliptical models of the underlying stellar emission were subtracted from the reduced and calibrated frames. The residual images show a number of morphological features not clearly seen before such as the faint extension at the end of the jet and faint red diffuse emission parallel to the jet on its northern side. The optical spectrum of the knots between the r and g bands is steeper than in the radio and, in general, becomes steeper with distance from the nucleus. The implications of this new result for particle acceleration mechanisms in jets are briefly discussed. The nondetection of a counterjet at an intensity level 300 times fainter than the jet places stronger constraints to relativistic beaming models of M87. 30 references.