Open AccessLocal circumstellar magnetic fields around evolved stars
Author(s) -
Soker Noam
Publication year - 2002
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2002.05817.x
Subject(s) - physics , stars , astrophysics , magnetic field , circumstellar envelope , astronomy , asymptotic giant branch , coherence (philosophical gambling strategy) , envelope (radar) , circumstellar disk , telecommunications , radar , quantum mechanics , computer science
I argue that the presence of magnetic fields around evolved stars, e.g. asymptotic giant branch stars, and in planetary nebulae, does not necessarily imply that the magnetic field plays a global dynamical role in shaping the circumstellar envelope. Instead, I favour magnetic fields with small coherence lengths, which result from stellar magnetic spots or from jets blown by an accreting companion. Although the magnetic field does not play a global role in shaping the circumstellar envelope, it may enhance local motion (turbulent) via magnetic tension and reconnection. The locally strong magnetic tension may enforce coherence flow, which may favour the masing process.