Protostars and Planets VI, Heidelberg, July 15-20, 2013

Poster 1K099

BIASES IN POPULATION STATISTICS INTRODUCED BY YSO MAGNETIC FIELDS

Deen, Casey (Max Planck Institut für Astronomie)

Abstract:
Timescales for star and planet formation derive from comparisons of the observed positions of young clusters in the HR diagram with theoretical isochrones. While there are many reasons to expect an intrinsic scatter in the HR diagram (initial conditions, accretion histories, duration of star formation), for the youngest clusters, the act of determining effective temperatures and luminosities is fraught with uncertainty. Using MoogStokes, a polarized radiative transfer code, to account for the effects of magnetic fields on the emergent spectra, I show that strong magnetic fields (of the strengths measured in young stellar objects) can significantly alter the appearance of the spectrum. Neglecting the effect of the magnetic field when determining properties of the young object (spectral type and luminosity) will artificially shift the location of the object in the HR diagram, biasing any statistics derived from a population of young objects. By properly accounting for the effects of the magnetic field, it is possible to a) properly place objects on the HR diagram, and b) measure magnetic field strengths in young objects

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