Stellar mid-life crisis: subcritical magnetic dynamos of solar-like stars and the breakdown of gyrochronology

  title={Stellar mid-life crisis: subcritical magnetic dynamos of solar-like stars and the breakdown of gyrochronology},
  author={Bindesh Tripathi and Dibyendu Nandy and Soumitro Banerjee},
Recent observations reveal the surprising breakdown of stellar gyrochronology relations at about the Sun’s age hinting that middle-aged, solar-like stars transition to a magnetically inactive future. We provide a theoretical basis for these intriguing observations inspired by simulations with a mathematical dynamo model that can explore long-term solar cycle fluctuations. We reproduce the observed bimodal distribution of sunspot numbers, but only for subcritical dynamos. Based on a bifurcation… Expand
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