Name/Affiliation: Oleksii Kuzmychov (Kiepenheuer-Institut für Sonnenphysik Freiburg, Germany)
Magnetic fields on brown dwarfs
We analyze the spectra of two brown dwarfs, which were obtained with the low resolution polarimeter LRIS (Keck observatory) in August 2012, in order to infer their magnetic properties. For doing this, we model polarimetric spectra of diatomic molecules - CrH, FeH, and TiO - and atomic lines. The objects observed exhibit transient but periodic radio pulses that are possibly driven by electron-cyclotron maser (Hallinan et al. 2007, 2008). For this mechanism to work, a few kG magnetic field is however required. In order to examine whether these objects possess such a strong magnetic field, we employ molecular spectropolarimetry (Berdyugina et al. 2000, 2005; Afram et al. 2008; Kuzmychov & Berdyugina 2013), that allows us to explore the magnetic fields in cool atmospheres of brown dwarfs and exoplanets. We are able to constrain the magnetic field strengths in these objects.