JWST/MIRI survey of 2-6 Myr Upper Scorpius disks finds diverse chemotypes, 10-1000x lower water luminosities, and evidence that outer dust traps control inner-disk chemistry.
Gas mass tracers in protoplanetary disks: CO is still the best
3 Pith papers cite this work. Polarity classification is still indexing.
abstract
Protoplanetary disk mass is a key parameter controlling the process of planetary system formation. CO molecular emission is often used as a tracer of gas mass in the disk. In this study we consider the ability of CO to trace the gas mass over a wide range of disk structural parameters and search for chemical species that could possibly be used as alternative mass tracers to CO. Specifically, we apply detailed astrochemical modeling to a large set of models of protoplanetary disks around low-mass stars, to select molecules with abundances correlated with the disk mass and being relatively insensitive to other disk properties. We do not consider sophisticated dust evolution models, restricting ourselves with the standard astrochemical assumption of $0.1~\mu $m dust. We find that CO is indeed the best molecular tracer for total gas mass, despite the fact that it is not the main carbon carrier, provided reasonable assumptions about CO abundance in the disk are used. Typically, chemical reprocessing lowers the abundance of CO by a factor of 3, compared to the case of photo-dissociation and freeze-out as the only ways of CO depletion. On average only 13% C-atoms reside in gas-phase CO, albeit with variations from 2 to 30%. CO$_2$, H$_2$O and H$_2$CO can potentially serve as alternative mass tracers, the latter two being only applicable if disk structural parameters are known.
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astro-ph.EP 3years
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UNVERDICTED 3roles
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A new grid of disk models with grain-surface CO chemistry plus an ML inference tool produces gas mass estimates from ALMA observations that match independent dynamical and HD values without requiring extreme elemental depletion.
2D radiation-hydrodynamical simulations find accretion outbursts unstable to Rossby-wave instability, forming vortices that suppress planetesimal formation until post-burst quiescence.
citing papers explorer
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Chemical Divergence and Water Depletion: Gas Properties of Evolved Upper Scorpius Disks Revealed by JWST/MIRI
JWST/MIRI survey of 2-6 Myr Upper Scorpius disks finds diverse chemotypes, 10-1000x lower water luminosities, and evidence that outer dust traps control inner-disk chemistry.
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DiskMINT-GARDEN: Self-consistent Models to Estimate Disk Masses
A new grid of disk models with grain-surface CO chemistry plus an ML inference tool produces gas mass estimates from ALMA observations that match independent dynamical and HD values without requiring extreme elemental depletion.
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Planet formation at the inner edge of the dead zone II. Outbursts, rings, vortices, and suppression of planetesimal formation
2D radiation-hydrodynamical simulations find accretion outbursts unstable to Rossby-wave instability, forming vortices that suppress planetesimal formation until post-burst quiescence.