Skip to main content
×
×
Home

Investigating Magnetic Activity in the Galactic Centre by Global MHD Simulation

  • Takeru K. Suzuki (a1) (a2), Yasuo Fukui (a2), Kazufumi Torii (a2) (a3), Mami Machida (a4), Ryoji Matsumoto (a5) and Kensuke Kakiuchi (a2)...
Abstract

By performing a global magnetohydrodynamical (MHD) simulation for the Milky Way with an axisymmetric gravitational potential, we propose that spatially dependent amplification of magnetic fields possibly explains the observed noncircular motion of the gas in the Galactic centre (GC) region. The radial distribution of the rotation frequency in the bulge region is not monotonic in general. The amplification of the magnetic field is enhanced in regions with stronger differential rotation, because magnetorotational instability and field-line stretching are more effective. The strength of the amplified magnetic field reaches ≳ 0.5 mG, and radial flows of the gas are excited by the inhomogeneous transport of angular momentum through turbulent magnetic field that is amplified in a spatially dependent manner. As a result, the simulated position-velocity diagram exhibits a time-dependent asymmetric parallelogram-shape owing to the intermittency of the magnetic turbulence; the present model provides a viable alternative to the bar-potential-driven model for the parallelogram shape of the central molecular zone. In addition, Parker instability (magnetic buoyancy) creates vertical magnetic structure, which would correspond to observed molecular loops, and frequently excited vertical flows. Furthermore, the time-averaged net gas flow is directed outward, whereas the flows are highly time dependent, which would contribute to the outflow from the bulge.

    • Send article to Kindle

      To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

      Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

      Find out more about the Kindle Personal Document Service.

      Investigating Magnetic Activity in the Galactic Centre by Global MHD Simulation
      Available formats
      ×
      Send article to Dropbox

      To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

      Investigating Magnetic Activity in the Galactic Centre by Global MHD Simulation
      Available formats
      ×
      Send article to Google Drive

      To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

      Investigating Magnetic Activity in the Galactic Centre by Global MHD Simulation
      Available formats
      ×
Copyright
References
Hide All
Balbus, S. A., & Hawley, J. F. 1991, ApJ, 376, 214
Bally, J., Stark, A. A., Wilson, R. W., & Henkel, C. 1987, ApJ, 65, 13
Chandrasekhar, S. 1961, Hydrodynamic and hydromagnetic stability (Oxford: Clarendon)
Crocker, R. M., Jones, D. I., Aharonian, F., et al. 2011, MNRAS, 411, L11
Fujishita, M., Torii, K., Kudo, N., et al. 2009, PASJ, 61, 1039
Fukui, Y., Yamamoto, H., Fujishita, M., et al. 2006, Science, 314, 106
Kudo, N., Torii, K., Machida, M., et al. 2011, PASJ, 63, 171
Lang, C. C., Morris, M., & Echevarria, L. 1999, ApJ, 526, 727
Liszt, H. S., & Burton, W. B. 1980, ApJ, 236, 779
Machida, M., Nakamura, K. E., Kudoh, T., et al. 2013, ApJ, 764, 81
Machida, M., Matsumoto, R., Nozawak, S., et al. 2009, PASJ, 61, 411
Miyamoto, M., & Nagai, R. 1975, PASJ, 27, 533
Nishikori, H., Machida, M., & Matsumoto, R. 2006, ApJ, 641, 862
Nishiyama, S., Hatano, H., Tamura, M., et al. 2010, ApJ, 722, L23
Parker, E. N. 1966, ApJ, 145, 811
Pillai, T., Kauffmann, J., Tan, J. C., et al. 2015, ApJ, 799, 74
Riquelme, D., Bronfman, L., Mauersberger, R., May, J., & Wilson, T. L. 2010, A&A, 523, A45
Shibata, K., & Matsumoto, R. 1991, Nature, 353, 633
Suzuki, T. K., Fukui, Y., Torii, K., Machida, M., & Matsumoto, R. 2015, MNRAS, 454, 3049
Suzuki, T. K., & Inutsuka, S.-i. 2009, ApJ, 691, L49
Suzuki, T. K., & Inutsuka, S.-i. 2014, ApJ, 784, 121
Suzuki, T. K., Muto, T., & Inutsuka, S.-i. 2010, ApJ, 718, 1289
Takeuchi, T., Yamamoto, H., Torii, K., et al. 2010, PASJ, 62, 557
Torii, K., Kudo, N., Fujishita, M., et al. 2010a, PASJ, 62, 1307
Torii, K., Kudo, N., Fujishita, M., et al. 2010b, PASJ, 62, 675
Tsuboi, M., Inoue, M., Handa, T., et al. 1986, AJ, 92, 818
Velikhov, E. P. 1959, Zh. Eksp. Teor. Fiz., 36, 1398
Yusef-Zadeh, F., Morris, M., & Chance, D. 1984, Nature, 310, 557
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Proceedings of the International Astronomical Union
  • ISSN: 1743-9213
  • EISSN: 1743-9221
  • URL: /core/journals/proceedings-of-the-international-astronomical-union
Please enter your name
Please enter a valid email address
Who would you like to send this to? *
×

Keywords

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 27 *
Loading metrics...

Abstract views

Total abstract views: 106 *
Loading metrics...

* Views captured on Cambridge Core between 9th February 2017 - 20th August 2018. This data will be updated every 24 hours.