We report R ∼ 4300 Very Large Telescope SINFONI adaptive optics integral field K-band spectroscopy of the nucleus of the Seyfert 1 galaxy NGC 3227 at a spatial resolution of 0.085 ′′ (7 pc). We present the morphologies and kinematics of emission lines and absorption features, and give the first derivation of a black hole mass in a Seyfert 1 nucleus from spatially resolved stellar dynamics. We show that the gas in the nucleus has a mean column density of order 10 24 -10 25 cm −2 and that it is geometrically thick, in agreement with the standard 'molecular torus' scenario. We discuss which heating processes may be responsible for maintaining the vertical height of the torus. We have also resolved the nuclear stellar distribution, and find that within a few parsecs of the AGN there has been an intense starburst. The most recent episode of which began ∼40 Myr ago but has now ceased. The current luminosity of stars within 30 pc of the AGN, ∼3 × 10 9 L ⊙ , is comparable to that of the AGN. Based on a comparison of the respective size scales, we argue that the star formation has been occuring in the obscuring torus. Finally, we present the first derivation of a black hole mass in a Seyfert 1 nucleus from stellar dynamics which marginally spatially resolve the black hole's sphere of influence. We apply Schwarzschild orbit superposition models to our full 2-dimensional data and derive the mass of the black hole, paying careful attention to the input parameters which are often uncertain: the contribution of the large scale bulge and its mass-to-light ratio; the recent star formation in the nucleus and its mass-to-light ratio; the contribution of the gas mass to the potential; and the inclination. Our models yield a 1σ range for the black hole mass of M BH = 7 × 10 6 -2 × 10 7 M ⊙ .
We present ∼ 0. ′′ 5 resolution near-infrared integral field spectroscopy of the Hα line emission of 14 z ∼ 2 UV-selected BM/BX galaxies, obtained with SINFONI at the ESO Very Large Telescope. The average Hα half-light radius is r 1/2 ≈ 4 h −1 70 kpc, and line emission is detected over 20 h −1 70 kpc in several sources. In nine galaxies, we detect spatially-resolved velocity gradients, from 40 to 410 km s −1 over ∼ 10 h −1 70 kpc. The observed kinematics of the larger systems are generally consistent with orbital motions. Four galaxies are well described by rotating disks with clumpy morphologies, and we extracted rotation curves out to radii 10 h −1 70 kpc. One or two galaxies exhibit signatures more consistent with mergers. Analyzing all 14 galaxies of the sample in the framework of rotating disks, we infer mean inclination-and beam-corrected maximum circular velocities of v c ∼ 180 ± 90 km s −1 and dynamical masses from ∼ 0.5 to 25 × 10 10 h −1 70 M ⊙ within r 1/2 . On average, the dynamical masses are consistent with estimates of photometric stellar masses assuming a Chabrier or Kroupa initial mass function (IMF) but too small for a 0.1 − 100 M ⊙ Salpeter IMF. The specific angular momenta of our BM/BX galaxies are similar to those of local late-type galaxies. In the single disk framework, the specific angular momenta of the baryons are comparable to those of their dark matter halos. Extrapolating from the average v c at 10 h −1 70 kpc, the virial mass of the typical halo of a galaxy in our sample is 10 11.7±0.5 h −1 70 M ⊙ , in good agreement with previous estimates from the clustering and number density of the BM/BX population. Kinematic modeling of the three best cases implies a ratio of v c to local velocity dispersion v c /σ ∼ 2 − 4 and accordingly a large geometric thickness. We argue that this suggests a mass accretion (alternatively, gas exhaustion) timescale of ∼ 500 Myr. We also argue that if our BM/BX galaxies were initially gas rich, their clumpy disks will subsequently lose their angular momentum and form compact bulges on a timescale of ∼ 1 Gyr. In support of this scenario, the object with brightest K-band magnitude and among the reddest in J − K colour in our sample (suggesting it is the most evolved) exhibits a maximum in [N II]/Hα ratio and a minimum in Hα equivalent width at the geometric/kinematic center, which we interpret as indicative of an inside-out metallicity and age gradient. mation and QSO activity at z ∼ 2 − 2.5 (e.g., Fan et al. 2001;Chapman et al. 2005).It is, however, less clear exactly how galaxies were assembled. In particular, when and at what rate did galaxies of different masses form? What is the connection between bulge and disk formation? Progress in solving these questions is hampered by our incomplete knowledge of various key physical and observational aspects. For instance, we still have a poor understanding of the competing processes of cooling, angular momentum exchange and loss, and feedback from star formation and active galactic nuclei (AGN), which drive galaxy ev...
SINFONI is an adaptive optics assisted near-infrared integral field spectrometer for the ESO VLT. The Adaptive Optics Module (built by the ESO Adaptive Optics Group) is a 60-elements curvature-sensor based system, designed for operations with natural or sodium laser guide stars. The near-infrared integral field spectrometer SPIFFI (built by the Infrared Group of MPE) provides simultaneous spectroscopy of 32 x 32 spatial pixels, and a spectral resolving power of up to 3300. The adaptive optics module is in the phase of integration; the spectrometer is presently tested in the laboratory. We provide an overview of the project, with particular emphasis on the problems encountered in designing and building an adaptive optics assisted spectrometer. 1. SINFONI: ADAPTIVE OPTICS AND INTEGRAL FIELD SPECTROSCOPY SINFONI (SINgle Faint Object Near-IR Investigation) is an adaptive optics assisted near infrared integral field spectrometer mounted to the European Southern Observatory (ESO) VLT (Very Large Telescope). The instrument is a combination ofthe Adaptive Optics module [1], a clone ofMACAO (Multiple Application Curvature Adaptive Optics), developed and built by ESO, and of the near infrared integral field spectrograph SPIFFI (SPectrograph for Infrared Faint Field Imaging) [2], developed and built by the Max-Planck-Institute for extraterrestrial Physics (MPE).Currently, ESO offers two state-of-the-art near infrared instruments at the VLT: ISAAC [3] for seeing limited infrared imaging and spectroscopy, and NAOS/CONICA [4,5] for high order adaptive optics imaging and low-resolution spectroscopy. However, spectroscopy of faint objects with diffraction limited angular resolution at an eight-meter telescope will strongly benefit from a dedicated instrument, which combines the following characteristics: first, diffraction limited observations at near infrared wavelengths, optimized for faint wave-front reference stars and laser guide star operations; second, instantaneous spectroscopy of a two dimensional field with sufficiently high spectral resolution for deep observations between the night sky emission lines.Both partner institutes collected extensive experience with diffraction-limited spectroscopy with their instruments ADONIS/SHARP [6] at the La Silla 3.6 m telescope, and ALFA/3D [7] at the Calar Alto Observatory 3.5 m telescope. Our conclusion is that when observing with adaptive optics, integral field spectroscopy gains significantly over long-slit spectroscopy and Fabry-Perot imaging. The latter suffers significantly from the variation of the sky emission and the point-spread-function (PSF) between consecutive images, and consumes exorbitant observing time for large wavelength coverage. Long-slit spectroscopy, on the other hand, lacks the essential two-dimensional information for decomposing the spatial flux distribution, and loses most ofthe source flux for a diffraction limited slit width and moderate correction of the atmospheric aberrations. In addition, flexure within the instruments complicates the acquisition of...
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