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SAC Seminar: Qian-Sheng Zhang - A solution to the "solar abundance problem"

26.08.2019 | Brigitte Christina Harke Henderson

Dato tor 29 aug
Tid 13:15 14:00
Sted 1520-732

Date: August 29 at 1:15pm

Title: A solution to the "solar abundance problem"

Abstract: Helioseismic observations have revealed many properties of the Sun: the depth and helium abundance of the convection zone, the sound speed, and the density profiles in the solar interior. Those constraints have been used to judge the stellar evolution theory. With the old solar composition (e.g., GS98), the solar standard model is in reasonable agreement with the helioseismic constraints. However, a solar model with a revised composition (e.g., AGSS09) with a low abundance Z of heavy elements cannot be consistent with those constraints. This is the so-called "solar abundance problem," standing for more than 10 yr even with the recent upward revised Ne abundance. Many mechanisms have been proposed to mitigate the problem. However, there is still no low-Z solar model satisfying all helioseismic constraints. In this paper, we report a possible solution to the solar abundance problem. With some extra physical processes that are not included in the standard model, solar models can be significantly improved. Our new solar models with convective overshoot, the solar wind, and early mass accretion show consistency with helioseismic constraints, the solar Li abundance, and observations of solar neutrino fluxes.

We look forward to seeing you there!

Best regards,

The SAC Seminar Team

Institut for Fysik og Astronomi, Medarbejdere, Offentligheden / Pressen, Studerende