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A new dynamo pattern revealed by the tilt angle of bipolar sunspot groups

Tlatov, A.; Illarionov, E.; Sokoloff, D. +1 more

We obtain the latitude-time distribution of the averaged tilt angle of solar bipoles. For large bipoles, which are mainly bipolar sunspot groups, the spatially averaged tilt angle is positive in the Northern solar hemisphere and negative in the Southern, with modest variations during the course of the solar cycle. We consider the averaged tilt ang…

Helioseismic calibration of the equation of state and chemical composition in the solar convective envelope

Vorontsov, S. V.; Baturin, V. A.; Ayukov, S. V. +1 more

Accurate and precise measurements of solar p-mode frequencies allow sensitive diagnostics of the adiabatic exponent Γ₁ = (∂ln p/∂ln ρ)_S as a function of depth in the adiabatically stratified part of the solar convective envelope. The profile of the adiabatic exponent contains information about the chemical composition of the …

Detecting exo-moons with photometric transit timing - I. Effect of realistic stellar noise

Lewis, Karen M.

The timing errors for individual planetary transits using the photometric transit timing technique (TTV_p) are derived for light curves contaminated with either white additive noise, realistic stellar noise or filtered stellar noise. For the case of white noise, the timing errors are derived analytically, while timing errors for realisti…

Spectropolarimetric investigation of the photosphere during a solar microflare

Kondrashova, N. N.

The results of the study of the thermodynamical parameters and the magnetic field in the solar photosphere during the solar microflare on 2009 July 4 in the active region NOAA 11024 are presented. The analysis is based on the observations with the French-Italian telescope THEMIS (Heliographic Telescope for the Study of the Magnetism and Instabilit…