Посилання:The temperature gradient in and around solar magnetic fluxtubes / V.A. Sheminova, R.J. Rutten, L.H.M. Rouppe van der Voort // Кинематика и физика небесных тел. — 2005. — Т. 21, № 5-додаток. — С. 110-116. — Бібліогр.: 14 назв. — англ.
Підтримка:We are grateful to the observing staff of the SVST for much assistance, to Sami Solanki for sharing his fluxtube codes, to Yakiv Pavlenko for computing the RE models, to Luis Bellot Rubio for advice on magnetostatic modelling, and to Daniel Roy for earlier insights from similar modelling of the outer Ca II H wings. The SVST was part of the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrof´ısica de Canarias and operated by the Royal Swedish Academy of Sciences. Our Utrecht–Oslo collaboration is part of the European Solar Magnetism Network supported by the European Commission under contract HPRN-CT-2002-00313, which also funds L. H. M. Rouppe van der Voort. Our Kyiv–Utrecht collaboration is supported by INTAS under contract 00-00084. V. A. Sheminova acknowledges hospitality at Utrecht. R. J. Rutten acknowledges travel support from the Leids Kerkhoven–Bosscha Fonds and hospitality in Kyiv.
We use spectra covering the outer part of the extended wing of the solar Ca II K line observed at high angular resolution with the Swedish Vacuum Solar Telescope to test standard solar fluxtube models. The wings of the Ca II resonance lines are formed in LTE both with regard to excitation (source function) and to ionization (opacity) and, therefore, sample temperature stratifications in relatively straightforward fashion. We obtain best fits by combining steeper temperature gradients than those in the standard models for both the tube inside and the tube environment. Similarly steep gradients are also determined from a numerical magnetoconvection simulation by the late A. S. Gadun. It is found that the energy balance in the individual magnetic elements appears to be close to radiative equilibrium throughout the photosphere.