| Name: | K M Hiremath |
| Affiliation: | Indian Institute of Astrophysics, Bengaluru-560034 |
| Conference ID : | ASI2024_90 |
| Title : | Origin of Sun's Near Surface Rotation Shear Layer: Evidence of Mass accretion During Early History of the Sun |
| Authors : | Hiremath, K. M |
| Authors Affiliation: | Indian Institute of Astrophysics, Koramangala, Bengaluru-560034 |
| Mode of Presentation: | Poster |
| Abstract Category : | Sun, Solar System, Exoplanets, and Astrobiology |
| Abstract : | Helioseismic inferences show that sun's rotational gradient increases and is positive from base of convection zone to 0.935 radius of the sun. Whereas near surface (from 0.935 to 1.0 sun's radius) rotational gradient decreases and is negative. Hydrodynamic and MHD simulations reproduce very well the rotational isocontours from base of the convection zone to 0.935 radius of the sun. Although, these studies apparently reproduce near surface rotational shear layer, one serious physical problem with such solutions is that negative rotational gradient near the surface does not satisfies MHD stability criterion unless the sun has acquired a strong steady large-scale toroidal magnetic field structure. Although helioseismic inferences have inferred such a strong toroidal magnetic field structure, its origin is not understood. Hence, if one accepts negative rotational gradient and toroidal magnetic field structure to coexist, inevitable explanation is probable planetary mass accretion on the surface during early history of the sun that can satisfactorily explains near surface rotational profile and other unsolved astrophysical problems such as "Faint Young Sun Paradox" and low mass terrestrial planets in the vicinity of the sun. |
