Institut national de recherche scientifique français Univerité Pierre et Marie Curie Université Paris Diderot - Paris 7

The Semel Polarimeter and the Anglo-Australian Telescope (AAT)

Friday 28 January 2011, by Ian Waite (University of Southern Queensland, Toowoomba, Australia)

Tuesday 28 September 2010 à 11h00 , Lieu : Salle de confĂ©rence du bât. 17

The Semel Polarimeter, developed by Meir Semel from LESIA, has been in use as a visitor instrument on the Australian Astronomical Telescope for the past 20 years to map the magnetic fields around various types of stars to produce a wealth of scientific results. Magnetic fields play a crucial role in the evolution of these stars. The key questions that we are currently investigating are “How do young stars actually generate magnetic fields and at what stage do these stars begin to produce solar-like magnetic cycles?”. Using the technique of Zeeman Doppler imaging we have mapped the magnetic field topology of a small number of young Sun-like stars at multiple epochs. This presentation outlines recent results from these observations and discusses implications for magnetic field generation and its evolution as these stars attempt to undergo magnetic reversals prior to the onset of the more familiar solar-like cycles.

Co-author: Stephen Marsden(University of Southern Queensland & James Cook University)