YSOVAR: Mid-infrared Variability of Young Stellar Objects and Their Disks in the Cluster IRAS 20050+2720

Author(s)
Katja Poppenhaeger, Ann Marie Cody, Kevin R. Covey, Hans Moritz Günther, Lynne A. Hillenbrand, Jan Forbrich
Abstract

We present a time-variability study of young stellar objects (YSOs) in the cluster IRAS 20050+2720, performed at 3.6 and 4.5 μm with the Spitzer Space Telescope; this study is part of the Young Stellar Object VARiability (YSOVAR) project. We have collected light curves for 181 cluster members over 60 days. We find a high variability fraction among embedded cluster members of ca. 70%, whereas young stars without a detectable disk display variability less often (in ca. 50% of the cases) and with lower amplitudes. We detect periodic variability for 33 sources with periods primarily in the range of 2–6 days. Practically all embedded periodic sources display additional variability on top of their periodicity. Furthermore, we analyze the slopes of the tracks that our sources span in the color–magnitude diagram (CMD). We find that sources with long variability time scales tend to display CMD slopes that are at least partially influenced by accretion processes, while sources with short variability timescales tend to display extinction-dominated slopes. We find a tentative trend of X-ray detected cluster members to vary on longer timescales than the X-ray undetected members.

Organisation(s)
Department of Astrophysics
External organisation(s)
Western Washington University, Harvard-Smithsonian Center for Astrophysics, National Aeronautics & Space Administration (NASA), California Institute of Technology (Caltech), Universität Hamburg
Journal
The Astronomical Journal
Volume
150
No. of pages
22
ISSN
0004-6256
DOI
https://doi.org/10.1088/0004-6256/150/4/118
Publication date
10-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Keywords
ASJC Scopus subject areas
Astronomy and Astrophysics, Space and Planetary Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/ysovar-midinfrared-variability-of-young-stellar-objects-and-their-disks-in-the-cluster-iras-200502720(caf1b19a-a673-4ee4-b298-10348ab848b9).html