(1) Stellar disks in the intermediate redshift range: listening to the galaxy evolution "Symphony". (2) Unveiling the narrow-line Seyfert 1 nature of Mrk 573 using near-infrared spectroscopy

Dr. Ruymán Azzollini, Dr. Cristina Ramos Almeida

Abstract

1) In this brief seminar (<~25 minutes+questions) I will present recent results on the study of "deep", high resolution, surface brightness profiles of a sample of ~500 late-type galaxies in the redshift range 0.1—1.1, making use of publicly available HST/ACS imaging of the GOODS-South field. We have classified and parameterized, according to usual prescriptions in this kind of analysis, these profiles, with special emphasis put on the so called ``truncated'' disks. This is the case in which, beyond a certain radius, termed as ``Break Radius'', the exponentially decaying surface brightness profile along the stellar disk gives way to an even more abrupt exponential decay. This radius can be taken as an spatial "scale" for the disk, as observed in a given band (in our case, the rest-frame B-band). Comparing with analogous analysis for galaxies in the Local Universe, as we have done, it is possible to extract valuable information on the evolution of several photometric properties of the stellar disks of galaxies, related to the stellar populations distributions. I will also present results on the analysis of the color profiles of this sample of galaxies, which have yield an interesting result which is, perhaps, the main reason that justifies calling this talk a "breaking news" seminar, as I will show. Summarizing, an overview of the results we have obtained will be given, and our conclusions on them, explaining how they can be understood in the frame of Galaxy Evolution (2) Based on high quality near-infrared spectroscopy (obtained with WHT/LIRIS) we reveal that the nucleus of Mrk 573 is an obscured Narrow-Line Seyfert 1 and not an archetypal Seyfert 2 as it has been classified until now. Currently only four AGNs have been classified into this category. We have detected permitted OI and FeII transitions, which indicates the existence of a high density region similar to the BLRs detected in type 1 AGN.

About the talk

(1) Stellar disks in the intermediate redshift range: listening to the galaxy evolution "Symphony". (2) Unveiling the narrow-line Seyfert 1 nature of Mrk 573 using near-infrared spectroscopy
Dr. Ruymán Azzollini, Dr. Cristina Ramos Almeida
Instituto de Estructura de la Materia, CSIC, Spain, University of Sheffield, UK
Thursday May 22, 2008 - 0:00  (Aula)
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