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In recent years evidence has been building that planet formation starts early, in the first $sim$ 0.5 Myr. Studying the dust masses available in young disks enables understanding the origin of planetary systems since mature disks are lacking the solid material necessary to reproduce the observed exoplanetary systems, especially the massive ones. We aim to determine if disks in the embedded stage of star formation contain enough dust to explain the solid content of the most massive exoplanets. We use Atacama Large Millimeter/submillimeter Array (ALMA) Band 6 observations of embedded disks in the Perseus star-forming region together with Very Large Array (VLA) Ka-band (9 mm) data to provide a robust estimate of dust disk masses from the flux densities. Using the DIANA opacity model including large grains, with a dust opacity value of $kappa_{rm 9 mm}$ = 0.28 cm$^{2}$ g$^{-1}$, the median dust masses of the embedded disks in Perseus are 158 M$_oplus$ for Class 0 and 52 M$_oplus$ for Class I from the VLA fluxes. The lower limits on the median masses from ALMA fluxes are 47 M$_oplus$ and 12 M$_oplus$ for Class 0 and Class I, respectively, obtained using the maximum dust opacity value $kappa_{rm 1.3mm}$ = 2.3 cm$^{2}$ g$^{-1}$. The dust masses of young Class 0 and I disks are larger by at least a factor of 10 and 3, respectively, compared with dust masses inferred for Class II disks in Lupus and other regions. The dust masses of Class 0 and I disks in Perseus derived from the VLA data are high enough to produce the observed exoplanet systems with efficiencies acceptable by planet formation models: the solid content in observed giant exoplanets can be explained if planet formation starts in Class 0 phase with an efficiency of $sim$ 15%. Higher efficiency of $sim$ 30% is necessary if the planet formation is set to start in Class I disks.
The increasing number of newly detected exoplanets at short orbital periods raises questions about their formation and migration histories. A particular puzzle that requires explanation arises from one of the key results of the Kepler mission, namely
Recent ALMA surveys of protoplanetary disks have shown that for most disks the extent of the gas emission is greater than the extent of the thermal emission of the millimeter-sized dust. Both line optical depth and the combined effect of radially dep
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We study a warping instability of a geometrically thin, non-self-gravitating, circumbinary disk around young binary stars on an eccentric orbit. Such a disk is subject to both the tidal torques due to a time-dependent binary potential and the radiati
The long-term evolution of a circumstellar disk starting from its formation and ending in the T Tauri phase was simulated numerically with the purpose of studying the evolution of dust in the disk with distinct values of viscous alpha-parameter and d