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arXiv · 0905.1807

Photometric monitoring of the young star Par 1724 in Orion

R. Neuhaeuser·A. Koeltzsch·St. Raetz·T. O. B. Schmidt·M. Mugrauer·N. Young·F. Bertoldi·T. Roell·T. Eisenbeiss·M. M. Hohle·M. Vanko·C. Ginski·W. Rammo·M. Moualla·C. Broeg
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Abstract

We report new photometric observations of the 200000 year old naked weak-line run-away T Tauri star Par 1724, located north of the Trapezium cluster in Orion. We observed in the broad band filters B, V, R, and I using the 90cm Dutch telescope on La Silla, the 80cm Wendelstein telescope, and a 25cm telescope of the University Observatory Jena in Grossschwabhausen near Jena. The photometric data in V and R are consistent with a 5.7 day rotation period due to spots, as observed before between 1960ies and 2000. Also, for the first time, we present evidence for a long-term 9 or 17.5 year cycle in photometric data (V band) of such a young star, a cycle similar to that to of the Sun and other active stars.

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R. Neuhaeuser, A. Koeltzsch, St. Raetz, T. O. B. Schmidt, M. Mugrauer, N. Young, F. Bertoldi, T. Roell, T. Eisenbeiss, M. M. Hohle, M. Vanko, C. Ginski, W. Rammo, M. Moualla, C. Broeg. 2009-05-12. Photometric monitoring of the young star Par 1724 in Orion. https://doi.org/10.1002/asna.200911196

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