Multi-Site observations of SU Aurigae

Y. C. Unruh; J. -F. Donati; J. M. Oliveira; A. Collier Cameron; C. Catala; H. F. Henrichs; C. M. Johns-Krull; B. Foing; J. Hao; H. Cao; J. D. Landstreet; H. C. Stempels; J. A. de Jong; J. Telting; N. Walton; P. Ehrenfreund; A. Hatzes; J. E. Neff; T. Böhm; T. Simon; L. Kaper; K. G. Strassmeier; Th. Granzer

doi:10.1111/j.1365-2966.2004.07445.x

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arXiv · astro-ph/0401081

Multi-Site observations of SU Aurigae

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Abstract

We present results from the 1996 MUSICOS (MUlti-SIte COntinuous Spectroscopy) campaign on the T Tauri star SU Aurigae. We find a 2.7-d periodicity in the He I (587.6 nm) line and somewhat longer, less well-pronounced periodicities in the Balmer lines and in Na D. Our observations support the suggestion that the wind and infall signatures are out of phase on SU Aur. We present Doppler images of SU Aur that have been obtained from least-squares deconvolved profiles. Images taken about one rotation apart show only limited overlap, in particular at low latitudes. This is in part due to limitations in signal-to-noise, and in part due to line profile deformations that arise from short-lived and/or non-surface features. The agreement at high latitudes is better and suggests that at least some longer-lived features are present. The analysis of Stokes V profiles yields a marginal magnetic field detection during one of the phases.

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Y. C. Unruh, J. -F. Donati, J. M. Oliveira, A. Collier Cameron, C. Catala, H. F. Henrichs, C. M. Johns-Krull, B. Foing, J. Hao, H. Cao, J. D. Landstreet, H. C. Stempels, J. A. de Jong, J. Telting, N. Walton, P. Ehrenfreund, A. Hatzes, J. E. Neff, T. Böhm, T. Simon, L. Kaper, K. G. Strassmeier, Th. Granzer. 2004-01-07. Multi-Site observations of SU Aurigae. https://doi.org/10.1111/j.1365-2966.2004.07445.x

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