KOPS - The Institutional Repository of the University of Konstanz

Magnetic buoyancy in simulated galactic discs with a realistic circum galactic medium

Magnetic buoyancy in simulated galactic discs with a realistic circum galactic medium

Cite This

Files in this item

Files Size Format View

There are no files associated with this item.

STEINWANDEL, Ulrich P., Marcus C. BECK, Alexander ARTH, Klaus DOLAG, Benjamin P. MOSTER, Peter NIELABA, 2019. Magnetic buoyancy in simulated galactic discs with a realistic circum galactic medium. In: Monthly Notices of the Royal Astronomical Society. 483(1), pp. 1008-1028. ISSN 0035-8711. eISSN 1365-2966. Available under: doi: 10.1093/mnras/sty3083

@article{Steinwandel2019Magne-44890, title={Magnetic buoyancy in simulated galactic discs with a realistic circum galactic medium}, year={2019}, doi={10.1093/mnras/sty3083}, number={1}, volume={483}, issn={0035-8711}, journal={Monthly Notices of the Royal Astronomical Society}, pages={1008--1028}, author={Steinwandel, Ulrich P. and Beck, Marcus C. and Arth, Alexander and Dolag, Klaus and Moster, Benjamin P. and Nielaba, Peter} }

Nielaba, Peter Magnetic buoyancy in simulated galactic discs with a realistic circum galactic medium 2019-02-07T09:15:41Z 2019-02-07T09:15:41Z Nielaba, Peter 2019 Steinwandel, Ulrich P. Dolag, Klaus eng Dolag, Klaus Arth, Alexander Moster, Benjamin P. Steinwandel, Ulrich P. We present simulations of isolated disc galaxies in a realistic environment performed with the Tree-SPMHD-Code Gadget<sub>-3</sub>. Our simulations include a spherical circum-galactic medium (CGM) surrounding the galactic disc, motivated by observations and the results of cosmological simulations. We present three galactic models with different halo masses between 10e<sup>10</sup> Msol and 10e<sup>12</sup> Msol, and for each we use two different approaches to seed the magnetic field, as well as a control simulation without a magnetic field. We find that the amplification of the magnetic field in the centre of the disc leads to a biconical magnetic outflow of gas that magnetizes the CGM. This biconical magnetic outflow reduces the star formation rate (SFR) of the galaxy by roughly 40 percent compared to the simulations without magnetic fields. As the key aspect of our simulations, we find that small scale turbulent motion of the gas in the disc leads to the amplification of the magnetic field up to tens of 10e-6 G, as long as the magnetic field strength is low. For stronger magnetic fields turbulent motion does not lead to significant amplification but is replaced by an alpha-omega dynamo. The occurance of a small scale turbulent dynamo becomes apparent through the magnetic power spectrum and analysis of the field lines' curvature. In accordance with recent observations we find an anti-correlation between the spiral structure in the gas density and in the magnetic field due to a diffusion term added to the induction equation. Beck, Marcus C. Arth, Alexander Beck, Marcus C. Moster, Benjamin P.

This item appears in the following Collection(s)

Search KOPS


Browse

My Account