Discovery of starspots on Vega. First spectrocopic detection of surface structures on a normal A-type star Torsten Bohm

Séminaire

6 janvier 2017

le 06 jan 2017 de11h00à 13h002017/01/06 2017/01/06

Discovery of starspots on Vega. First spectrocopic detection of surface structures on a normal A-type star

The results of an in depth analysis of a data set consisting of 7000 high resolution spectra of Vega is presented. Standard A-type stars have extended radiative zones and should therefore not show any signatures of surface structures linked to magnetic activity. Surprisingly enough, such surface structures have unambiguously been discovered on Vega.

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