On the structure and energetics of large scale hydromagnetic disturbances in the solar photosphere

We have investigated the temporal evolution of the solar magnetic field during solar cycles 20, 21 and 22 by means of spherical harmonic decomposition and subsequent time series analysis. A 33 yr and a 25 yr time series of daily magnetic maps of the solar photosphere, recorded at the Mt. Wilson and NSO/Kitt Peak observatories respectively, were used to calculate the spherical coefficients of the radial magnetic field. Fourier and wavelet analysis were then applied to deduce the temporal variations. We compare the results of the two datasets and present examples of zonal modes which show significant variations, e. g. with a period of approx. 2.0—2.5 years. We provide evidence that this quasi-biennial oscillation originates mainly from the southern hemisphere. Furthermore, we show that low degree modes with odd l — m exhibit periods of 29.2 and 28.1 days while modes with even l — m show a dominant period of 26.9 days. A resonant modal structure of the solar magnetic field (apart from the 22 yr cycle) has not been found.

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Large-scale horizontal flows in the solar photosphere

Astronomy and Astrophysics ◽

10.1051/0004-6361/200912422 ◽

2009 ◽

Vol 506 (2) ◽

pp. 875-884 ◽

Cited By ~ 6

Author(s):

M. Švanda ◽

M. Klvaňa ◽

M. Sobotka

Keyword(s):

Large Scale ◽

Solar Photosphere ◽

Horizontal Flows

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Evidence for large-scale oscillations of the solar photosphere

The Astrophysical Journal ◽

10.1086/181641 ◽

1974 ◽

Vol 193 ◽

pp. L97 ◽

Cited By ~ 1

Author(s):

E. Fossat ◽

G. Ricort ◽

C. Aime ◽

F. Roddier

Keyword(s):

Large Scale ◽

Solar Photosphere

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On the structure and energetics of large scale hydromagnetic disturbances in the solar photosphere

Tellus ◽

10.3402/tellusa.v17i3.9074 ◽

1965 ◽

Vol 17 (3) ◽

pp. 334-340 ◽

Cited By ~ 2

Author(s):

Victor P. Starr ◽

Peter A. Gilman

Keyword(s):

Large Scale ◽

Solar Photosphere

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Relationship between magnetic field properties and statistical flow using numerical simulation and magnetic feature tracking on solar photosphere

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab710 ◽

2021 ◽

Vol 503 (3) ◽

pp. 3610-3616

Author(s):

K Takahata ◽

H Hotta ◽

Y Iida ◽

T Oba

Keyword(s):

Magnetic Field ◽

Magnetic Properties ◽

Differential Rotation ◽

Large Scale ◽

Solar Interior ◽

Dimensional Structure ◽

Magnetic Feature ◽

Solar Photosphere ◽

Solar Dynamics Observatory ◽

Large Scale Flow

ABSTRACT We perform radiative magnetohydrodynamic calculations for the solar-quiet region to investigate the dependence of statistical flow on magnetic properties and the three-dimensional structure of magnetic patches in the presence of large-scale flow that mimics differential rotation. It has been confirmed that strong magnetic field patches move faster in the longitudinal direction at the solar surface. Consequently, strong magnetic patches penetrate deeper into the solar interior. The motion of the deep-rooted magnetic patches is influenced by the faster differential rotation in the deeper layer. In this study, we perform realistic radiative magnetohydrodynamic calculations using r2d2 code to validate that stronger patches have deeper roots. We also add large-scale flow to mimic the differential rotation. The magnetic patches are automatically detected and tracked, and we evaluate the depth of 30 000 magnetic patches. The velocities of 2.9 million magnetic patches are then measured at the photosphere. We obtain the dependence of these values on the magnetic properties, such as field strength and flux. Our results confirm that strong magnetic patches tend to show deeper roots and faster movement, and we compare our results with observations using the point spread function of instruments at the Hinode and Solar Dynamics Observatory (SDO). Our result is quantitatively consistent with previous observational results of the SDO.

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Large-scale horizontal flows in the solar photosphere

Astronomy and Astrophysics ◽

10.1051/0004-6361:20077718 ◽

2007 ◽

Vol 477 (1) ◽

pp. 285-292 ◽

Cited By ~ 12

Author(s):

M. Švanda ◽

M. Klvaňa ◽

M. Sobotka ◽

V. Bumba

Keyword(s):

Large Scale ◽

Solar Photosphere ◽

Horizontal Flows

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Large-scale transport of solar and stellar magnetic flux

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319004587 ◽

2018 ◽

Vol 14 (A30) ◽

pp. 347-350

Author(s):

Emre Işık

Keyword(s):

Magnetic Fields ◽

Magnetic Flux ◽

Large Scale ◽

Surface Flux ◽

Current Understanding ◽

Solar Photosphere ◽

The Sun ◽

Forward Modelling ◽

Flux Transport ◽

Brightness Variability

AbstractSurface flux transport (SFT) models have been successful in reproducing how magnetic flux at the solar photosphere evolves on large scales. SFT modelling proved to be useful in reconstructing secular irradiance variations of the Sun, and it can be potentially used in forward modelling of brightness variations of Sun-like stars. We outline our current understanding of solar and stellar SFT processes, and suggest that nesting of activity can play an important role in shaping large-scale patterns of magnetic fields and brightness variability.

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