Seminario DAS: Unveiling variable stars in our Galaxy, from squalling newborns to old smokers

Speaker: Dr. Zhen Guo 
Affiliation: Instituto de Fisica y Astronomia, Universidad de Valparaiso. 

Abstract: There are more than 100 billion stars in our Milky Way Galaxy, and almost all types of stars exhibit stellar variability triggered by various physical mechanisms. The study of stellar variation provides key information in astrophysics, such as the formation, evolution, and final stagesof a star's life. In the past decade, the VVV survey team has been closely monitoring variable stars located towards the centre of our Galaxy, using the  VISTA telescope in Chile. In this talk, I will present our latest results on searching and classifying large-amplitude variable stars in the infrared wavelengths. Some of these variables are young stellar objects exhibiting outbursting behaviours, and the rest are evolved post-main-sequence red giant stars with temporary dimming events. These discoveries have raised concerns about the current theoretical models of stellar evolution. Finally, I will briefly introduce our future plans with Rubin and Mozi telescopes.