February 2-5, 2021

Oral Presentation

IR pseudo-observations of merger driven DOGs and their evolution

Author(s): Naomichi Yutani (Kagoshima University)

Presenter: naomichi Yutani (kagoshima university)

Dust-Obscured Galaxies (DOGs) are optically faint and infrared bright galaxies. They are important population to understand the evolution of galaxies and AGN (Active Galactic Nuclei). In this talk, I will present the evolution of two-color diagrams and SED based on N-body/SPH simulations of galaxy mergers and radiative transfer calculations.

Narayanan et al. (2010) claimed that the formation of DOGs is thought to be due to galaxy mergers. Based on SEDs, there are two sub-categories in DOGs; Bump DOGs (hereafter B-DOGs) and Power-law DOGs (hereafter P-DOGs). The origin of B-DOGs and P-DOGs is not clear, but Narayana+(2010) pointed out that starburst and AGN, respectively dominate them. In their simulation, sub-grid physics is assumed in the structure of 100 pc or smaller. However, it is needed to resolve a torus-scale (i.e., 10 pc or smaller) to understand the ISM structures in the nuclear region and how this relates to the AGN activity and DOGs. Therefore, we focus on the final phase of galaxy mergers using high-resolution (8pc) N-body/SPH simulations. We use N-body/SPH code ASURA (Saitoh et al. 2008, 2009). We then obtained the time evolution of SED of the system by the radiative transfer simulation code RADMC-3D (Dullemond et al. 2012).

We succeeded in reproducing properties of DOGs, e.g., the WISE color and IR luminosity during the evolution. Besides, we identified B-DOGs and P-DOGs from the pseudo-observations. We found that even P-DOGs, which are dominated by AGN, have properties of as B-DOGs depending on the column density.

ASIAA will not contact participants for credit card information by phone. Privacy and Security Policy