ABSENCE OF SIGNIFICANT COOL DISKS IN YOUNG STELLAR OBJECTS EXHIBITING REPETITIVE OPTICAL OUTBURSTS

作者：Liu Hauyu Baobab; Galvan Madrid Roberto; Vorobyov Eduard I; Kospal Agnes; Rodriguez Luis F; Dunham Michael M; Hirano Naomi; Henning Thomas; Takami Michihiro; Dong Ruobing; Hashimoto Jun; Hasegawa Yasuhiro; Carrasco Gonzalez Carlos

来源：Astrophysical Journal Letters, 2016, 816(2): L29.

DOI：10.3847/2041-8205/816/2/L29

• stars: formation

We report Submillimeter Array 1.3 mm high angular resolution observations toward the four EXor-type outbursting young stellar objects VY Tau, V1118 Ori, V1143 Ori, and NY Ori. The data mostly show low dust masses Mdust in the associated circumstellar disks. Among the sources, NY Ori possesses a relatively massive disk with M-dust similar to 9 x 10(-4) M-circle dot. V1118 Ori has a marginal detection equivalent to M-dust similar to 6 x 10(-5) M-circle dot. V1143 Ori has a non-detection also equivalent to M-dust < 6 x 10(-5) M-circle dot. For the nearest source, VY Tau, we get a surprising non-detection that provides a stringent upper limit M-dust < 6 x 10(-6) M-circle dot. We interpret our findings as suggesting that the gas and dust reservoirs that feed the short-duration, repetitive optical outbursts seen in some EXors may be limited to the small-scale, innermost region of their circumstellar disks. This hot dust may have escaped our detection limits. Follow-up, more sensitive millimeter observations are needed to improve our understanding of the triggering mechanisms of EXor-type outbursts.

• 出版日期2016-1-10
• 单位中国科学院; 中国科学院国家天文台