Gemini NIFS survey of feeding and feedback processes in nearby Active Galaxies: I - Stellar kinematics

We use the Gemini Near-Infrared Integral Field Spectrograph (NIFS) to map the stellar kinematics of the inner few hundred parsecs of a sample of 16 nearby Seyfert galaxies, at a spatial resolution of tens of parsecs and spectral resolution of 40 km/s. We find that the line-of-sight (LOS) velocity fields for most galaxies are well reproduced by rotating disk models. The kinematic position angle (PA) derived for the LOS velocity field is consistent with the large scale photometric PA. The residual velocities are correlated with the hard X-ray luminosity, suggesting that more luminous AGN have a larger impact in the surrounding stellar dynamics. The central velocity dispersion values are usually higher than the rotation velocity amplitude, what we attribute to the strong contribution of bulge kinematics in these inner regions. For 50% of the galaxies, we find an inverse correlation between the velocities and the $h_3$ Gauss-Hermitte moment, implying red wings in the blueshifted side and blue wings in the redshifted side of the velocity field, attributed to the movement of the bulge stars lagging the rotation. Two of the 16 galaxies (NGC 5899 and Mrk 1066) show an S-shape zero velocity line, attributed to the gravitational potential of a nuclear bar. Velocity dispersion maps show rings of low-$\sigma$ values (50-80 km/s) for 4 objects and "patches" of low-sigma for 6 galaxies at 150-250 pc from the nucleus, attributed to young/ intermediate age stellar populations.Comment: To be published in MNRA

Report on Chemical Analysis and Further Dating of Dinosaur Bones and Dinosaur Petroglypths

Much of the material in this report was presented at the 1990 ICC poster sessions. Our radiocarbon dates of dinosaur bones and the other information in this report should be alarming to the evolutionary community and should be given serious study considering our preliminary results

A Decade of Near-Infrared Variability in NGC4388: Insights into the AGN Structure

Variability studies have proven to be a powerful diagnostic tool for understanding the physics and properties of of Active Galactic Nuclei (AGNs). They provide insights into the spatial and temporal distribution of the emitting regions, the structure and dynamics of the accretion disk, and the properties of the central black hole. Here, we have analysed the K-band spectral variability of the Seyfert 1.9/2 galaxy NGC4388 spanning five epochs over a period of ten years. We have performed spectral synthesis of the nuclear region and found that the contribution of warm dust (T~800K) declined by 88% during these 10 years. In the same period, the [CaVIII] coronal line decreased 61%, whereas BrG emission declined 35%. For the HeI and H2, we did not detect any significant variation beyond their uncertainties. Based on the time span of these changes, we estimate that the region where the warm dust is produced is smaller than 0.6pc, which suggests that this spectral feature comes from the innermost part of the region sampled, directly from the AGN torus. On the other hand, the bulk of [CaVIII] is produced in the inner ~2pc and the nuclear BrG region is more extended, spanning a region larger than 3pc. Lastly, HeI and H2 are even more external, with most of the emission probably being produced in the host galaxy rather than in the AGN. This is the first spectroscopic variability study in the NIR for an AGN where the central source is not directly visible.Comment: Accepted in MNRAS. 8 pages, 3 figure

Influência do tempo de condução de agroflorestas na atividade microbiológica do solo.

A atividade biológica é um ótimo indicador de qualidade do solo, pois é um atributo sensível ás características bióticas e abióticas do sistema. A fim de quantificar esses atributos, foram coletadas amostras de solo nas profundidades de 0 a 2,5 cm, 2,5 a 5 cm, 5 a 10 cm, 10 a 15 cm, 15 a 30 cm, 30 a 45 cm e 45 a 60 cm para obtenção do carbono da biomassa microbiana (BMS-C), respiração basal do solo (RBS) e quociente metabólico (qCO2) em áreas de regeneração natural de 10 anos e agroflorestas de 5 e 10 anos. As áreas de regeneração natural apresentaram teores mais elevados de BMS-C e maior RBS, porém maiores qCO2 foram encontrados nas agroflorestas de 10 anos devido ao manejo utilizado nas agroflorestas.Resumo expandido