Abstract
Two-dimensional simulations of time-dependent solar magnetogranulation are used to analyze the horizontal magnetic fields and the response of the synthesized Stokes profiles of the IR FeI λ1564.85 nm line to the magnetic fields. The 1.5-h series of MHD models used for the analyses reproduces a region of the magnetic network in the photosphere with an unsigned magnetic flux density of 192 G at the solar surface. According to the magnetic-field distribution obtained, the most probable absolute strength of the horizontal magnetic field at an optical depth of τ 5 = 1(τ 5 denotes τ at λ = 500 nm) is 50 G, while the mean value is 244 G. On average, the horizontal magnetic fields are stronger than the vertical fields to heights of about 400 km in the photosphere due to their higher density and the larger area they occupy. The maximum factor by which the horizontal fields are greater is 1.5. Strong horizontal magnetic flux tubes emerge at the surface as spots with field strengths of more than 500 G. These are smaller than granules in size, and have lifetimes of 3–6 min. They form in the photosphere due to the expulsion of magnetic fields by convective flows coming from deep subphotospheric layers. The data obtained qualitatively agree with observations with the Hinode space observatory.
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T. Kosugi, K. Matsuzaki, T. Sakao, et al., Solar Phys. 243, 3 (2007).
B. Lites, H. Socas-Navarro, M. Kubo, et al., Publ. Astron. Soc. Japan 59, 571 (2007).
B. Lites, M. Kubo, H. Socas-Navarro, et al., Astrophys. J. 460, 1237 (2008).
B. Lites, K. D. Leka, A. Skumanich, et al., Astrophys. J. 460, 1019 (1996).
N. Meunier, S. K. Solanki, and W. C. Livingston, Astron. Astrophys. 331, 771 (1998).
B. Lites, A. Skumanich, and V. Martinez Pillet, Astron. Astrophys. 333, 1053 (1998).
B. De Pontieu, Astrophys. J. 569, 474 (2002).
M. J. Martinez González, M. Collados, B. Ruiz Cobo, and S. K. Solanki, Astron. Astrophys. 469, L39 (2007).
R. Centeno, H. Socas-Navarro, B. Lites, et al., Astrophys. J. 666, L137 (2007).
D. Orozco Suárez, L. R. Bellot Rubio, J. C. del Toro Iniesta, et al., Astrophys. J. 670, L61 (2007).
J. W. Harvey, D. Branston, C. J. Henney, and C. U. Keller, Astrophys. J. 659, L177 (2007).
R. Ishikawa, S. Tsuneta, K. Ichimoto, et al., Astron. Astrophys. 481, L25 (2008).
U. Grossmann-Doerth, M. Schüssler, and O. Steiner, Astron. Astrophys. 337, 928 (1998).
A. S. Gadun, V. A. Sheminova, and S. K. Solanki, Kinemat. Fiz. Nebesn. Tel 15(5), 387 (1999).
A. S. Gadun, S. K. Solanki, V. A. Sheminova, and S. R. O. Ploner, Solar Phys. 203, 1 (2001).
W. Schaffenberger, S. Wedemeyer-Bohm, O. Steiner, and B. Freytag, in Solar MHD Theory and Observations, Ed. by J. Leibacher, R. E. Stein, and H. Uitenbroek, ASP Conf. Ser. 354, 345 (2006).
O. Steiner, R. Rezaei, W. Schaffenberger, and S. Wedemeyer-Bohm, Astrophys. J. 680, L85 (2008).
M. Schüssler and A. Vögler, Astron. Astrophys. 481, L5 (2008).
O. Steiner, in Modern Solar Facilities-Advanced Solar Science, Ed. by F. Kneer, K. G. Puschmann, and A. D. Wittmann (Universitatsverlag, Göttingen, 2007).
M. Asplund, H.-G. Ludwig, Å. Nordlund, and R. F. Stein, Astron. Astrophys. 359, 669 (2000).
A. S. Gadun, S. K. Solanki, and A. Johannesson, Astron. Astrophys. 350, 1018 (1999).
S. R. O. Ploner, S. K. Solanki, and A. S. Gadun, Astron. Astrophys. 352, 679 (1999).
I. N. Atroshchenko and V. A. Sheminova, Kinemat. Fiz. Nebesn. Tel 12(4), 32 (1996).
A. S. Gadun, Kinemat. Fiz. Nebesn. Tel 16(2), 99 (2000).
V. A. Sheminova and A. S. Gadun, Astron. Zh. 77, 790 (2000) [Astron. Rep. 44, 701 (2000)].
W. Deinzer, G. Hensler, M. Schüssler, and E. Weisshaar, Astron. Astrophys. 139, 435 (1984).
P. N. Brandt and A. S. Gadun, Kinemat. Fiz. Nebesn. Tel 11(4), 44 (1995).
S. R. O. Ploner, M. Schüssler, S. K. Solanki, and A. S. Gadun, in Advanced Solar Polarimetry—Theory, Observation, and Instrumentation, Ed. by M. Sigwarth, ASP Conf. Ser. 236, 363 (2001).
R. F. Stein and Å. Nordlund, in IAU Colloquim 188: Magnetic Coupling of the Solar Atmosphere, Ed. by H. Sawaya-Lacoste (ESA Publ. Division, 2002), p. 83.
L. R. Bellot Rubio, R. Luis, I. Rodrígues Hidalgo, et al., Astron. Astrophys. 560, 1010 (2001).
S. R. O. Ploner, M. Schüssler, S. K. Solanki, et al., in Advanced Solar Polarimetry—Theory, Observation, and Instrumentation, Ed. by M. Sigwarth, ASP Conf. Ser. 236, 371 (2001).
V. A. Sheminova, Kinemat. Fiz. Nebesn. Tel 21(3), 172 (2005) [Kinem. Phys. Celest. Bodies 21, 120 (2005)].
V. A. Sheminova, Solar Phys. 254, 29 (2009).
A. Vögler, S. Shelyag, M. Schüssler, et al., Astron. Astrophys. 429, 335 (2005).
R. F. Stein and Å. Nordlund, Astrophys. J. 642, 1246 (2006).
B.W. Lites, Astrophys. J. 573, 431 (2002).
J. Sánchez Almeida, Astron. Astrophys. 450, 1198 (2006).
I. Domínguez Cerdeña, J. Almeida Sánchez, and F. Kneer, Astrophys. J. 407, 741 (2003).
P. S. Barklem, N. Piskunov, and B. J. O’Mara, Astron. Astrophys. Suppl. Ser. 142, 467 (2000).
V. A. Sheminova, Calculating the Profiles of Stokes Parameters of Magnetoactive Absorption Lines in Stellar Atmospheres, Dep. VINITI May 30, 1990, No. 2940-V90 (Kiev, Ukraina, 1990) [in Russian].
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Original Russian Text © V.A. Sheminova, 2009, published in Astronomicheskiĭ Zhurnal, 2009, Vol. 86, No. 5, pp. 518–528.