English
Related papers

Related papers: Dynamo Saturation in Rapidly Rotating Solar-Type S…

200 papers

The Babcock-Leighton dynamo, which relies on the generation of a poloidal field through the decay and dispersal of tilted bipolar magnetic regions (BMRs), is a promising paradigm for explaining the features of the solar magnetic cycle. In…

Solar and Stellar Astrophysics · Physics 2025-12-12 Vindya Vashishth , Bidya Binay Karak

Observations show that faster-rotating stars tend to have stronger magnetic activity and shorter magnetic cycles. The cyclical magnetic activity of the Sun and stars is believed to be driven by the dynamo process. The success of the…

Solar and Stellar Astrophysics · Physics 2024-06-05 Zebin Zhang , Jie Jiang , Leonid Kitchatinov

The Sun and solar-type stars exhibit irregular cyclic variations in their magnetic activity over long time scales. To understand this irregularity, we employed the flux transport dynamo models to investigate the behavior of one solar mass…

Solar and Stellar Astrophysics · Physics 2024-12-25 Vindya Vashishth

Observations of the solar magnetic cycle showed that the amplitude of the cycle did not grow all the time in the past. Thus, there must be a mechanism to halt the growth of the magnetic field in the Sun. We demonstrate a recently proposed…

Solar and Stellar Astrophysics · Physics 2021-02-02 Bidya Binay Karak

We present results from a three-dimensional Babcock--Leighton dynamo model that is sustained by the explicit emergence and dispersal of bipolar magnetic regions (BMRs). On average, each BMR has a systematic tilt given by Joy's law.…

Solar and Stellar Astrophysics · Physics 2017-09-22 Bidya Binay Karak , Mark Miesch

Stellar dynamos are driven by complex couplings between rotation and turbulent convection, which drive global-scale flows and build and rebuild stellar magnetic fields. When stars like our sun are young, they rotate much more rapidly than…

We attempt to provide a quantitative theoretical explanation for the observations that Ca II H/K emission and X-ray emission from solar-like stars increase with decreasing Rossby number (i.e., with faster rotation). Assuming that these…

Solar and Stellar Astrophysics · Physics 2014-07-30 Bidya Binay Karak , Leonid L. Kitchatinov , Arnab Rai Choudhuri

Observations of chromospheric and coronal emissions from various solar-type stars show that the stellar magnetic activity varies with the rotation rates of the stars. The faster the star rotates, its magnetic activity gets stronger but…

Solar and Stellar Astrophysics · Physics 2019-10-16 Gopal Hazra , Jie Jiang , Bidya Binay Karak , Leonid Kitchatinov

Like the solar cycle, stellar activity cycles are also irregular. Observations reveal that rapidly rotating (young) Sun-like stars exhibit a high level of activity with no Maunder-like grand minima and rarely display smooth regular activity…

Solar and Stellar Astrophysics · Physics 2023-05-10 Vindya Vashishth , Bidya Binay Karak , Leonid Kitchatinov

Stellar magnetic activity of solar like stars is thought to be due to an internal dynamo. While the Sun has been the subject of intense research for refining dynamo models, observations of magnetic cyclic activity in solar type stars have…

Solar and Stellar Astrophysics · Physics 2015-06-03 Olivier Do Cao , Allan Sacha Brun

Stellar activity is fundamental to stellar evolution and the formation and habitability of exoplanets. The interaction between convective motions and rotation in cool stars results in a dynamo process that drives magnetic surface activity.…

In this work, we have studied the variability and frequency of occurrence of the grand minima using kinematic dynamo models of one solar mass star with different rotation rates and depths of convection zones. We specify the large-scale…

Solar and Stellar Astrophysics · Physics 2022-12-06 Vindya Vashishth

Using a new catalog of 824 solar and late-type stars with X-ray luminosities and rotation periods we have studied the relationship between rotation and stellar activity. From an unbiased subset of this sample the power law slope of the…

Solar and Stellar Astrophysics · Physics 2015-06-11 Nicholas J. Wright , Jeremy J. Drake , Eric E. Mamajek , Gregory W. Henry

We present a sample of 824 solar and late-type stars with X-ray luminosities and rotation periods. This is used to study the relationship between rotation and stellar activity and derive a new estimate of the convective turnover time. From…

Solar and Stellar Astrophysics · Physics 2015-05-30 Nicholas J. Wright , Jeremy J. Drake , Eric E. Mamajek , Gregory W. Henry

This paper proposes the idea that the observed dependence of stellar activity cycles on rotation rate can be a manifestation of a stronger dependence on the effective temperature. Observational evidence is recalled and theoretical arguments…

Solar and Stellar Astrophysics · Physics 2023-06-26 Leonid Kitchatinov

In Sun and sun-like stars, it is believed that the cycles of the large-scale magnetic field are produced due to the existence of differential rotation and helicity in the plasma flows in their convection zones (CZs). Hence, it is expected…

Solar and Stellar Astrophysics · Physics 2021-12-08 Vindya Vashishth , Bidya Binay Karak , Leonid Kitchatinov

One interpretation of the activity and magnetism of late-type stars is that these both intensify with decreasing Rossby number up to a saturation level, suggesting that stellar dynamos depend on both rotation and convective turbulence. Some…

Solar and Stellar Astrophysics · Physics 2020-03-23 Jyri J. Lehtinen , Federico Spada , Maarit J. Käpylä , Nigul Olspert , Petri J. Käpylä

We explore the cause of the solar cycle variabilities using a novel 3D Babcock--Leighton dynamo model. In this model, based on the toroidal flux at the base of the convection zone, bipolar magnetic regions (BMRs) are produced with…

Solar and Stellar Astrophysics · Physics 2019-01-30 Bidya Binay Karak , Mark Miesch

We present statistically robust observational evidence which imposes new limits on dynamo saturation in young solar-type stars. These are inferred from the increasing amplitude of the V-band optical flux with rotation, caused by the filling…

Astrophysics · Physics 2007-05-23 Mark A. O'Dell , Peter M. Panagi , Martin A. Hendry , Andrew Collier-Cameron

The solar magnetic activity cycle has an amplitude that varies within a wide but limited range of values. This implies that there are nonlinear mechanisms that prevent runaway solutions. The purpose of this paper is to propose observable…

Solar and Stellar Astrophysics · Physics 2020-09-02 Jie Jiang
‹ Prev 1 2 3 10 Next ›