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تسجيل مستخدم جديدDiagnosing 0.1-10 au scale morphology of the FU,Ori disk using ALMA and VLTI/GRAVITY
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We report new Atacama Large Millimeter/submillimeter Array Band 3 (86-100 GHz; $sim$80 mas angular resolution) and Band 4 (146-160 GHz; $sim$50 mas angular resolution) observations of the dust continuum emission towards the archetypal and ongoing accretion burst young stellar object FU Ori, which simultaneously covered its companion, FU Ori S. In addition, we present near-infrared (2-2.45 $mu$m) observations of FU Ori taken with the General Relativity Analysis via VLT InTerferometrY (GRAVITY; $sim$1 mas angular resolution) instrument on the Very Large Telescope Interferometer (VLTI). We find that the emission in both FU Ori and FU Ori S at (sub)millimeter and near infrared bands is dominated by structures inward of $sim$10 au radii. We detected closure phases close to zero from FU Ori with VLTI/GRAVITY, which indicate the source is approximately centrally symmetric and therefore is likely viewed nearly face-on. Our simple model to fit the GRAVITY data shows that the inner 0.4 au radii of the FU Ori disk has a triangular spectral shape at 2-2.45 $mu$m, which is consistent with the H$_{2}$O and CO absorption features in a $dot{M}sim$10$^{-4}$ $M_{odot},yr^{-1}$, viscously heated accretion disk. At larger ($sim$0.4-10 au) radii, our analysis shows that viscous heating may also explain the observed (sub)millimeter and centimeter spectral energy distribution when we assume a constant, $sim$10$^{-4}$ $M_{odot},yr^{-1}$ mass inflow rate in this region. This explains how the inner 0.4 au disk is replenished with mass at a modest rate, such that it neither depletes nor accumulates significant masses over its short dynamic timescale. Finally, we tentatively detect evidence of vertical dust settling in the inner 10 au of the FU Ori disk, but confirmation requires more complete spectral sampling in the centimeter bands.
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FU Orionis objects are low-mass pre-main sequence stars characterized by dramatic outbursts of several magnitudes in brightness. These outbursts are linked to episodic accretion events in which stars gain a significant portion of their mass. The phys
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We have studied the environment of the FU Ori type star V582 Aur. Our aim is to explore the star-forming region associated with this young eruptive star. Using slitless spectroscopy we searched for H alpha emission stars within a field of 11.5arcmin
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