Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-06-04
Astronomy and Astrophysics
Astrophysics
18 pages, 5 figures, accepted to Astron. Lett
Scientific paper
10.1134/S1063773708110054
The model that describes operation of dynamo in fully convective stars is presented. It is based on representation of stellar magnetic field as a superposition of finite number of poloidal and toroidal free damping modes. In the frame of adopted low of stellar differential rotation we estimated minimal value of dynamo number D, starting from which generation of cyclic magnetic field in stars without radiative core is possible. We also derived expression for period of the cycle. It was found that dynamo cycles of fully convective stars and stars with thin convective envelopes differ in a qualitative way: 1) distribution of spots over latitude during the cycle is different in these stars; 2) the model predicts that spot formation in fully convective stars should be strongly suppressed at some phases of the cycle. We have analyzed historical lightcurve of WTTS star V410 Tau and found that long term activity of the star is not periodic process. Rather one can speak about quasi cyclic activity with characteristic time of $\sim 4$ yr and chaotic component over imposed. We concluded also that redistribution of cool spots over longitude is the reason of long term variations of V410 Tau brightness. It means that one can not compare directly results of photometric observations with predictions of our axially symmetric (for simplicity) model which allows to investigate time evolution of spot's distribution over latitude. We then discuss what kind of observations and in which way could be used to check predictions of the dynamo theory.
Ermash A. A.
Lamzin Sergei A.
Nefedov S. N.
Sokoloff Dimitry
No associations
LandOfFree
The model of dynamo with small number of modes and magnetic activity of T Tauri stars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The model of dynamo with small number of modes and magnetic activity of T Tauri stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The model of dynamo with small number of modes and magnetic activity of T Tauri stars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-154408