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Short Talks da Pós-Graduação (Astrofísica extragaláctica)

10 de abril: 12:30 - 13:30

Palestrante: Janaina Correa do Nascimento
Titulo: TBC
Resumo: TBC
Palestrante: Luis Gabriel Dahmer Hahn
Título: A panchromatic spatially resolved study of the inner 500pc of NGC1052 – II: Gas excitation and kinematics
Resumo: We map the optical and near-infrared properties of the emission lines of the inner 320x535pc² of the elliptical galaxy NGC 1052. The optical and NIR spectra were obtained using the Integral Field Units of GMOS and NIFS, respectively. We detect four kinematical components. A broad line visible in Ha, with a FWHM of ~3200km/s. An intermediate-width component with 280<FWHM<450km/s and central peak velocities up to 400km/s, which dominates the flux in our data. Two narrow (FWHM<150km/s) emissions, one visible in [OIII], suggesting a nuclear flow, and one visible in the other emission lines, extending beyond the field-of-view of our data, compatible with a previously detected component which was attributed to large-scale shocks. Our results suggest that the ionization of this region cannot be explained by a single mechanism, with shocks being the dominant mechanism in the nucleus and an ionization cone in the same direction of the radio jets of this galaxy, responsible for the extended ionization.
Palestrante: Emilio Zanatta
Título: Extragalactic Star Clusters – GCs in M87 and Nuclear Star Clusters in Coma
Resumo: In this talk I will present results obtained studying the fraction of nuclear star clusters in the Coma cluster and the rich globular cluster system of the giant elliptical M87 in the Virgo cluster. In the first part, I will talk about the peculiar high amount of nucleated galaxies in Coma when compared to Virgo and Fornax clusters. On the second half, I will show the what I’ve been working on so far trying to solve the questions posed by Powalka et al. 2016 regarding current popular stellar population models and the GC system of M87. For this end, I’ve been working with new NIR data from the very center of M87 as well as optical data from the literature and new stellar population models accounting for abundance variations.
Palestrante: Fernanda Roman de Oliveira
Título: Diving deep into jellyfish galaxies
Resumo: Existing research recognises the critical role played by environment on galaxy evolution.  However, the mechanisms behind the morphological change and quenching of galaxies are not fully understood. In dense environments, ram pressure stripping (RPS) is an important physical mechanism that transforms galaxies by depleting their interstellar gas content through a hydrodynamic friction as the galaxies fall into the intracluster medium. Jellyfish galaxies, the most striking examples of galaxies undergoing RPS, are a key element to understand this problem.  Little is known about the characteristics of the irregular morphologies of these objects and it is not clear what factors contribute to the following steps on the evolution of the stripped galaxies. By employing a quantitative measurement of morphometric indicators with the software Morfometryka, we attempt to achieve a deeper understanding on how the RPS affects the morphologies of jellyfish galaxies. Our findings suggest that jellyfish galaxies share more similarities with irregular dwarf galaxies than to lenticular galaxies, which was previously proposed as an outcome of the RPS phase.
Palestrante: Augusto Lassen
Título: TBC
Palestrante: Mônica Tergolina
Título: Probing the luminous and dark matter profiles in the inner regions of a group-scale lens at z=0.6
Resumo: Studying the density profiles of galaxy groups offers an important insight on how large scale structure in the Universe formed and evolved, since galaxy groups bridge the gap between individual galaxies and galaxy clusters. We aim to probe the density profile of the galaxy group that is gravitational lensing HELMS18, a dusty star-forming galaxy at $z=2.39$ from the Herschel’s HerMES Large Mode Survey (HELMS), by using strong gravitational lensing. We will use high-resolution data of HELMS18 obtained with the Atacama Large Millimeter/submillimeter Array (ALMA). Using the semi-linear inversion method we will model these data, recovering mass properties of the group-scale lens and also intrinsic properties of the high-redshift lensed galaxy.
Palestrante: Bruno Dall’Agnol de Oliveira
Titulo: The feedback power of luminous type 2 AGNs
Resumo: The existence of Supermassive Black Holes in galactic nuclei can produce great amounts of radiation, when matter is accreted through its accretion disk. We analyzed the influence of this radiation in the interstellar medium gas, studying a sample of 9 luminous quasars (L[OIII]λ5007 > 10^42 erg/s), with narrow band images from Hubble Space Telescope. We found that the high excitation gas have the same bipolar morphology observed in less luminous Active Galactic Nuclei, still indicating the presence of the dust torus for these high luminosities. Presently, I am studying the kinematics of this sample using integral field spectroscopy (with GMOS-IFU), in order to measure the effects of a possible feedback. I will show the preliminary results of this new work.
Palestrante: Nicolas Dullius Mallmann
TItulo: TBC
Resumo: TBC


10 de abril
12:30 - 13:30


Anfiteatro Antonio Cabral