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arXiv · 1901.03815

Osaka Feedback Model: Isolated Disk Galaxy Simulations

Ikkoh Shimizu·Keita Todoroki·Hidenobu Yajima·Kentaro Nagamine
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Abstract

We study various implementations of supernova feedback model and present the results of our `Osaka feedback model' using isolated galaxy simulations performed by the smoothed particle hydrodynamics (SPH) code {\small GADGET-3}. Our model is a modified version of Stinson et al.'s work, and we newly add the momentum kick for SN feedback rather than only thermal feedback. We incorporate the physical properties of SN remnants from the results of Chevalier and McKee \& Ostriker, such as the effective radius of SN bubble and the remnant life-time, in the form of Sedov-Taylor (ST)-like solutions with the effect of radiative cooling. Our model utilizes the local, physical parameters such as density and temperature of the ISM rather than galactic or halo properties to determine the galactic wind velocity or mass-loading factor. The Osaka model succeeds in self-regulating star formation, and naturally produces galactic outflow with variable velocities depending on the local environment and available SN energy as a function of time.An important addition to our previous work by Aoyama et al. is the implementation of the {\small CELib} chemistry library which allows us to deal with the time-dependent input of energy and metal yields for type Ia \& II supernovae (SNe) and asymptotic giant branch (AGB) stars. As initial tests of our model, we apply it to isolated galaxy simulations, and examine various galactic properties and compare with observational data including metal abundances.

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Ikkoh Shimizu, Keita Todoroki, Hidenobu Yajima, Kentaro Nagamine. 2019-01-12. Osaka Feedback Model: Isolated Disk Galaxy Simulations. https://doi.org/10.1093/mnras%2Fstz098

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