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Black holes with a mass a million times the mass of our Sun or more—i.e., supermassive black holes—tend to reside in galactic centers. The mass of a supermassive black hole scales with the mass and stellar velocity dispersion of the bulge of the host galaxy. Thus, the central supermassive black hole in a galaxy appears to grow in conjunction with its host, but the physical mechanisms leading to such a coupling are not yet understood. Accreting supermassive black holes also comply with similar scaling relationships, which suggests that the accretion process plays an important role in the evolution of the host galaxy. We are exploring this question using a multiwavelength investigation of a sample of about 130 nearby southern galaxies that have accreting supermassive black holes. This study began as the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7), and we have obtained integral field spectroscopy for the central regions of all 130 of the galaxies. Radio-imaging follow-up work is ongoing, using the Giant Metre-Wave Radio Telescope and the Australia Telescope Compact Array. Several individual galaxies in our sample have been studied in detail as well. All of our data are intended for public release, with the first two releases already done. We present a brief status report of our investigation. [ABSTRACT FROM AUTHOR]

We derived the mass distribution of 8 nearby E-Sb galaxies from the CALIFA survey (http://califa.caha.es/). The two-dimensional stellar kinematics has been obtained with the PPAK integral-field spectrograph on the 3.5-m telescope at the Calar Alto Observatory. We solved the Jeans equations in the axisymmetric case and constructed dynamical models. The circular velocity curves of our sample's elliptical galaxies, E, show higher dynamical masses than the spirals, S0/Sb. The dark matter fractions of the galaxies were inferred by comparing the total dynamical mass-to-light ratio (M/L)dyn with the stellar mass-to-light ratio (M/L)pop estimated by fitting stellar population models. (M/L)dyn/(M/L)pop is above one for all galaxies and higher for the ellipticals than the spirals. The brightest galaxies from our sample are the most dark matter dominated objects. [ABSTRACT FROM AUTHOR]

The new integral-field spectrograph MUSE will acquire hyperspectral images of the deep sky, requiring huge amounts of raw data to be processed, posing a challenge to modern algorithms and technologies. In order to achieve the required sensitivity to observe very faint objects, many observations need to be reconstructed and co-added into a single data cube. In this paper, we propose a new fusion method to combine all raw observations while removing most of the instrumental and observational artifacts such as blur or cosmic rays. Thus, the results can be accurately and consistently analyzed by astronomers. We use a Bayesian framework allowing for optimal data fusion and uncertainty estimation. The knowledge of the instrument allows to write the direct problem (data acquisition on the detector matrix) and then to invert it through Bayesian inference, assuming a smoothness prior for the data cube to be reconstructed. Compared to existing methods, the originality of the new technique is in the propagation of errors throughout the fusion pipeline and the ability to deal with various acquisition parameters for each input image. For this paper, we focus on small-size, simulated astronomical observations with varying parameters to validate the image formation model, the reconstruction algorithm and the predicted uncertainties. [ABSTRACT FROM AUTHOR]

During the 2004–2008 period the Nearby Supernova Factory discovered ∼1000 supernovæ, and obtained detailed spectrophotometric time series of ∼190 SNe Ia with the SuperNova Integral Field Spectrograph. These supernovæ are located in the nearby Hubble flow (0.03

We discuss two-dimensional mapping of the near-infrared emission-line intensity distributions and kinematics of the narrow-line region (NLR) of NGC 4151, obtained with the Gemini Near-Infrared Integral Field Spectrograph, with a projected spatial resolution of ≈8 pc. The ionized gas intensity distribution follows the projected bi-cone morphology observed in previous optical narrow-band images, and its kinematics reveal outflows along the bi-cone. We propose a kinematic model in which the gas in the NLR moves at a velocity of ≈600 km s-1 up to ∼100 pc from the nucleus. A completely distinct morphology and kinematic structure is observed for the molecular gas, which avoids the region of the bi-cone and has velocities close to systemic, and is consistent with an origin in the galaxy plane. The molecular gas thus traces the AGN feeding, while the ionized gas traces its feedback. [ABSTRACT FROM AUTHOR]

I report results of recent integral field spectroscopy of the inner few hundred parsecs (pc) around nearby Active Galactic Nuclei (AGN) at a sampling of a few pc, obtained with the Gemini Telescopes. In the lowest activity AGNs, it is possible to observe inflows in ionized gas along nuclear spirals and filaments. In more luminous AGN inflows have been observed also in hot molecular gas (H2) emission in the near-IR. In most cases the H2 kinematics is dominated by circular rotation in the plane around the nucleus, tracing the AGN feeding. The ionized gas, on the other hand, traces the AGN feedback. Its kinematics shows two components: (1) one originating in the plane, and dominated by circular rotation; (2) another outflowing along the Narrow-Line Region (NLR) whose flux distribution and kinematics frequently correlate with structures seen in radio maps. Mass outflow rates along the NLR range from 10-2 to 1 M⊙ yr-1, corresponding to 10–100 times the accretion rate to the AGN, indicating that most of the NLR gas mass has been entrained from the galaxy plane. The average kinetic power of the NLR outflows is ≈10-4 times the bolometric luminosity. [ABSTRACT FROM AUTHOR]

Although very successful (more than 350 planets discovered up to now), indirect methods for extrasolar planet detection (Radial velocities, transits) are sensitive to planets quite close to their hosts. Moreover, accurate studies of the planet characteristics are feasible only for a subset of objects which are strongly irradiated by their parent stars. High contrast imaging will be the new frontier of exoplanets search and characterization. This technique will provide the opportunity to have at once a deep glance in the neighborhood of the target star in a yet unexplored region of star-planet separation. The possibility to couple integral field spectrograph to extreme adaptive optics module at the focus of 8 m telescope class (SPHERE for VLT and GPI for south Gemini) and in future to ELTs (EPICS) gives also the possibility to have a first order characterization of the exoplanets themselves. Here we present the potentiality of the high contrast imaging with the detection and characterization capability of the new planet finder instruments comparing them with the RVs and transit methods. [ABSTRACT FROM AUTHOR]

We obtained medium-resolution infrared K-band integral field spectroscopy with VLT/Sinfoni for the brown dwarf TWA 5 B, a companion to the weak-line T Tauri star TWA 5 in the TW Hya association. We compare the final spectrum with theoretical model atmospheres from DRIFT-PHOENIX (Dehn et al. 2007, Helling et al. 2008 ab, Witte 2008) for temperature from 2000 to 3100 K, gravity log g = 3.0, 3.5, and 4.0 (g in cm/s2) and metallicity -0.5, 0.0 (solar), and 0.5; we also varried the extinction towards TWA 5 B while searching for the best-fit model between Av = 0.0 and 15 mag. The best-fitting model spectrum yields the following parameters for TWA 5 B: Effective temperature Teff≃2800 K, metallicity [M/H]≃-0.5 (for metal content M), surface gravity log g≃4.0, and extinction Av = 0.0 mag. From these parameters and the distance towards TWA (∼65 pc), we can compute the mass of the brown dwarf to be roughly 25 Jupiter masses, but with large error bars including massive planets and low-mass stars. Given its projected separation from the primary star, ∼123 AU, it has certainly more likely formed star-like, i.e. being a brown dwarf companion. [ABSTRACT FROM AUTHOR]

Integral field (“3D”) spectroscopy is an emerging observing technique in the process of becoming a common user tool, with a variety of powerful instruments becoming available at most major observatories. The application of this new method has a number of advantages over conventional techniques for both extended and point sources. We describe our experience with 3D spectroscopy applied to extremely low surface brightness regions in haloes of galactic planetary nebulae, and to extragalactic planetary nebulae in local group galaxies. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

We use the Integral Field Spectrograph VIMOS to map the physical parameters in a sample of 24 star forming galaxies selected from the SDSS database. Among the most important parameters that we derive are the dynamical mass and star formation rate. We present examples of the maps that we obtain and demonstrate their potential with a case study of the interacting Seyfert 1.9 LEDA 135736. [ABSTRACT FROM AUTHOR]

We present here the first results of a research project devoted to the characterization of the physical properties of the planetary nebulae haloes. We succeeded in determining some properties in the halo of NGC 3242, but we did not detect any halo feature down to the detection limit in NGC 4361. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]