Magneto-hydrodynamic simulations of galactic gaseous disk

2015 Fiscal Year Final Research Report

• Project/Area Number: 23740153
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Astronomy
• Research Institution: Kyushu University
• Principal Investigator: Machida Mami 九州大学, 理学(系)研究科(研究院), 助教 (50455200)
• Project Period (FY): 2011-04-28 – 2016-03-31
• Keywords: 銀河ガス円盤 / 磁気流体数値実験 / 磁気乱流 / 観測的可視化 / 理論天文学

Outline of Final Research Achievements

We performed three-dimensional magneto-hydrodynamic simulations of galactic gaseous disk due to clarify a mechanism of amplification of galactic magnetic fields. The weak toroidal magnetic fields we assumed initially are amplified by magneto-rotational instability. When the magnetic pressure amplified by MRI became comparable to the gas pressure, magnetic fields are buoyantly rising to the halo region and the ratio of gas pressure to magnetic pressure reached quasi-steady state. We also performed observational visualization using the simulation data. We calculated synchrotron intensity and polarized intensity. The intensity map of GHz-bands traced the magnetic spiral arms inside the galactic disk. On the other hands, halo magnetic fields are observed in MHz-bands.

Free Research Field

理論天文学