Skip to content

Research at St Andrews

Global-scale consequences of magnetic-helicity injection and condensation on the sun

Research output: Contribution to journalArticle

Author(s)

Duncan Hendry Mackay, Rick DeVore, Spiro Antiochos

School/Research organisations

Abstract

In the recent paper of Antiochos, a new concept for the injection of magnetic helicity into the solar corona by small-scale convective motions and its condensation onto polarity inversion lines (PILs) has been developed. We
investigate this concept through global simulations of the Sun’s photospheric and coronal magnetic fields, and compare the results with the hemispheric pattern of solar filaments. Assuming that the vorticity of the cells is
predominately counter-clockwise/clockwise in the northern/southern hemisphere, the convective motions inject negative/positive helicity into each hemisphere. The simulations show that: (1) on a north–south oriented PIL,
both differential rotation and convective motions inject the same sign of helicity, which matches that required to reproduce the hemispheric pattern of filaments. (2) On a high-latitude east–west oriented polar crown or subpolar
crown PIL, the vorticity of the cells has to be approximately 2–3 times greater than the local differential-rotation gradient in order to overcome the incorrect sign of helicity injection from differential rotation. (3) In the declining
phase of the cycle, as a bipole interacts with the polar field, in some cases, helicity condensation can reverse the effect of differential rotation along the east–west lead arm but not in all cases. The results show that this
newly developed concept of magnetic helicity injection and condensation, in conjunction with the mechanisms used in Yeates et al., is a viable explanation for the hemispheric pattern of filaments. Future observational studies
should focus on examining the vorticity component within convective motions to determine both its magnitude and latitudinal variation relative to the differential-rotation gradient on the Sun.
Close

Details

Original languageEnglish
Article number164
Number of pages15
JournalAstrophysical Journal
Volume784
Issue number2
DOIs
Publication statusPublished - 1 Apr 2014

    Research areas

  • Magnetic fields - sun, Activity - sun, Corona

Discover related content
Find related publications, people, projects and more using interactive charts.

View graph of relations

Related by author

  1. Understanding the plasma and magnetic field evolution of a filament using observations and non-linear force-free field modelling: evolution of an intermediate filament

    Yardley, S. L., Savcheva, A., Green, L. M., van Driel-Gesztelyi, L., Long, D., Williams, D. R. & Mackay, D. H., 23 Dec 2019, In : Astrophysical Journal. 887, 2, 14 p., 240.

    Research output: Contribution to journalArticle

  2. A space weather tool for identifying eruptive active regions

    Pagano, P., Mackay, D. H. & Yardley, S. L., 22 Nov 2019, In : Astrophysical Journal. 886, 2, 81.

    Research output: Contribution to journalArticle

  3. Nonlinear force-free field modeling of solar coronal jets in theoretical configurations

    Meyer, K. A., Savcheva, A. S., Mackay, D. H. & DeLuca, E. E., 25 Jul 2019, In : Astrophysical Journal. 880, 1, p. 1-13 13 p., 62.

    Research output: Contribution to journalArticle

  4. Observing the simulations: applying ZDI to 3D non-potential magnetic field simulations

    Lehmann, L. T., Hussain, G. A. J., Jardine, M. M., Mackay, D. H. & Vidotto, A. A., 11 Mar 2019, In : Monthly Notices of the Royal Astronomical Society. 483, 4, p. 5246–5266

    Research output: Contribution to journalArticle

Related by journal

  1. A cancellation nanoflare model for solar chromospheric and coronal heating. II. 2D theory and simulations

    Syntelis, P., Priest, E. R. & Chitta, L. P., 7 Feb 2019, In : Astrophysical Journal. 872, 1, 15 p., 32.

    Research output: Contribution to journalArticle

  2. A space weather tool for identifying eruptive active regions

    Pagano, P., Mackay, D. H. & Yardley, S. L., 22 Nov 2019, In : Astrophysical Journal. 886, 2, 81.

    Research output: Contribution to journalArticle

  3. Estimating magnetic filling factors from Zeeman–Doppler magnetograms

    See, V., Matt, S. P., Folsom, C. P., Saikia, S. B., Donati, J-F., Fares, R., Finley, A. J., Hébrard, É. M., Jardine, M. M., Jeffers, S. V., Lehmann, L. T., Marsden, S. C., Mengel, M. W., Morin, J., Petit, P., Vidotto, A. A. & Waite, I. A., 9 May 2019, In : Astrophysical Journal. 876, 2, 118.

    Research output: Contribution to journalArticle

  4. First determination of 2D speed distribution within the bodies of coronal mass ejections with cross-correlation analysis

    Ying, B., Bemporad, A., Giordano, S., Pagano, P., Feng, L., Lu, L., Li, H. & Gan, W., 23 Jul 2019, In : Astrophysical Journal. 880, 1, 14 p., 41.

    Research output: Contribution to journalArticle

Related by journal

  1. Astrophysical Journal (Journal)

    Carolin Villforth (Reviewer)
    2011 → …

    Activity: Publication peer-review and editorial work typesPeer review of manuscripts

  2. Astrophysical Journal (Journal)

    Christiane Helling (Reviewer)
    1 Jan 200631 Dec 2017

    Activity: Publication peer-review and editorial work typesPeer review of manuscripts

  3. Astrophysical Journal (Journal)

    Duncan Hendry Mackay (Editor)
    1997 → …

    Activity: Publication peer-review and editorial work typesEditor of research journal

  4. Astrophysical Journal (Journal)

    Alan William Hood (Editor)
    1980 → …

    Activity: Publication peer-review and editorial work typesEditor of research journal

ID: 5312680

Top