A crucial but unexplored chromosphere line for measuring stellar helium abundances

Stellar helium abundance is an important stellar parameter which can shed light on the formation history of globular cluster and even galactic bulge.
However, it is hard to be measured since only the helium 10830A chromospheric line presents in A-K type stars. To test its potential to become a helium an abundance tracer of these stars, I will introduce the formation mechanism of this helium line, the cross-match result of previous equivalent width measurement with recent surveys.

 
Speaker: 
Mingjie Jian (Tokyo U)
Place: 
1st meeting room, KIAA
Time: 
Friday, September 27, 2019 - 12:00PM to Friday, September 27, 2019 - 1:00PM