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تسجيل مستخدم جديدA 1.3 mm SMA Survey of 29 Variable Young Stellar Objects
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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/gas reservoirs to each other, and whether or not their dust/gas reservoirs are similar as quiescent YSOs, are issues not yet clarified. 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). We have carried out extensive Submillimeter Array (SMA) observations mostly at $sim$225 GHz (1.33 mm) and $sim$272 GHz (1.10 mm), from 2008 to 2017. We covered accretion outburst YSOs located at $<$1 kpc distances from the solar system. We analyze all the existing SMA data of such objects, both published and unpublished, in a coherent way to present a millimeter interferometric database of 29 objects.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 $sim$1$$ angular resolution. Overall our observed targets show a systematically higher millimeter luminosity distribution than those of the $M_{*}>$0.3 $M_{odot}$ Class II YSOs in the nearby ($lesssim$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 $sim$30-60% millimeter flux variability from V2494 Cyg and V2495 Cyg, from the observations separated by $sim$1 year.
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