A 1.3 mm SMA survey of 29 variable young stellar objects

作者:Liu Hauyu Baobab*; Dunham Michael M; Pascucci Ilaria; Bourke Tyler L; Hirano Naomi; Longmore Steven; Andrews Sean; Carrasco Gonzalez Carlos; Forbrich Jan; Galvan Madrid Roberto; Girart Josep M; Green Joel D; Juarez Carmen; Kospal Agnes; Manara Carlo F; Palau Aina; Takami Michihiro; Testi Leonardo; Vorobyov Eduard I
来源:Astronomy & Astrophysics, 2018, 612: A54.
DOI:10.1051/0004-6361/201731951

摘要

Context. Young stellar objects (YSOs) may undergo periods of active accretion (outbursts), during which the protostellar accretion rate is temporarily enhanced by a few orders of magnitude. Whether or not these accretion outburst YSOs possess similar dust and gas reservoirs to each other, and whether or not their dust and gas reservoirs are similar as quiescent YSOs, are issues yet to be clarified. Aims. The aim of this work is to characterize the millimeter thermal dust emission properties of a statistically significant sample of long and short duration accretion outburst YSOs (i.e., FUors and EXors) and the spectroscopically identified candidates of accretion outbursting YSOs (i.e., FUor-like objects).& para;& para;Methods. We have carried out extensive Submillimeter Array (SMA) observations mostly at similar to 225 GHz (1.33 mm) and similar to 272 GHz (1.10 mm), from 2008 to 2017. We covered accretion outburst YSOs located at <1 kpc distances from the solar system.& para;& para;Results. We analyze all the existing SMA data of such objects, both published and unpublished, in a coherent way to present a millimeter interferometric database of 29 objects. We obtained 21 detections at >3 sigma significance. Detected sources except for the two cases of V883 Ori and NGC 2071 MM3 were observed with similar to 1" angular resolution. Overall our observed targets show a systematically higher millimeter luminosity distribution than those of the M-* > 0.3 M-circle dot Class II YSOs in the nearby (less than or similar to 400 pc) low-mass star-forming molecular clouds (e.g., Taurus, Lupus, Upp Scorpio, and Chameleon I). In addition, at 1 mm our observed confirmed binaries or triple-system sources are systematically fainter than the rest of the sources even though their 1 mm fluxes are broadly distributed. We may have detected similar to 30-60% millimeter flux variability from V2494 Cyg and V2495 Cyg, from the observations separated by approximately one year.

  • 出版日期2018-4-20