The search for large scale coherent stellar magnetic fields, Dr. Mark Slovak (UHM Physics)

Thursday Apr 7, 2016, 3:15 PM → 4:45 PM Pacific/Honolulu

WAT 112 (Watanabe Hall)

The quantum mechanical derivation of the strong-field Zeeman effect (splitting of spectral lines of atoms in an external magnetic field) is briefly reviewed and illustrated by the mercury (Hg) 435.80 nm sigma Zeeman quartet. An overview of stellar magnetism in the Hertzsprung-Russell (H-R) diagram is presented, illustrated by solar magnetism as the only extant example of spatially resolved, time dependent stellar magnetic field mapping. Magnetic observations of bright post main sequence giant stars (symbiotic and VV Cephei variables) using a multichannel photoelectric Zeeman analyzer at the coude focus of the McDonald Observatory 2.7 m telescope illustrate the difficulty of high precision stellar magnetic field determinations (+/- 100 Gauss) and contradict earlier photographic determinations claiming large fields.