The Waldmeier effect and the flux transport solar dynamo

Autor:	Karak, Bidya Binay, Choudhuri, Arnab Rai
Rok vydání:	2010
Předmět:	Astrophysics - Solar and Stellar Astrophysics Astrophysics - Earth and Planetary Astrophysics Astrophysics - High Energy Astrophysical Phenomena
Zdroj:	Monthly Notices Roy. Astron. Soc. 410, 1503-1512 (2011)
Druh dokumentu:	Working Paper
DOI:	10.1111/j.1365-2966.2010.17531.x
Popis:	We confirm that the evidence for the Waldmeier effect WE1 (the anti-correlation between rise times of sunspot cycles and their strengths) and the related effect WE2 (the correlation between rise rates of cycles and their strengths) is found in different kinds of sunspot data. We explore whether these effects can be explained theoretically on the basis of the flux transport dynamo models of sunspot cycles. Two sources of irregularities of sunspot cycles are included in our model: fluctuations in the poloidal field generation process and fluctuations in the meridional circulation. We find WE2 to be a robust result which is produced in different kinds of theoretical models for different sources of irregularities. The Waldmeier effect WE1, on the other hand, arises from fluctuations in the meridional circulation and is found only in the theoretical models with reasonably high turbulent diffusivity which ensures that the diffusion time is not more than a few years. Comment: Being reviewed in MNRAS
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1008.0824 Zobrazit plný text záznamu View this record from Arxiv