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We present the Atacama Large Millimeter/submillimeter Array Survey of Gas Evolution of PROtoplanetary Disks (AGE-PRO), a large program of the ALMA. AGE-PRO aims to systematically trace the evolution of gas disk mass and size throughout the lifetime of protoplanetary disks. It uses a carefully selected sample of 30 disks around M3-K6 stars in three nearby star-forming regions: Ophiuchus (0.5–1 Myr), Lupus (1–3 Myr), and Upper Sco (2–6 Myr). Assuming the three regions had similar initial conditions and evolutionary paths, we find the median gas disk mass appears to decrease with age. Ophiuchus disks have the highest median gas mass (6MJup), while the Lupus and Upper Sco disks have significantly lower median masses (0.68 and 0.44MJup, respectively). Notably, the gas and dust disk masses appear to evolve on different timescales. This is evidenced by the median gas-to-dust mass ratio, which decreases from 122 in the youngest disks (<1 Myr) to 46 in Lupus disks, and then increases to 120 in the Upper Sco disks. The median gas disk sizes range between 74 and 110 au, suggesting that typical gas disks are much smaller than those of well-studied, massive disks. Population synthesis models suggest that magnetohydrodynamic wind-driven accretion can reproduce median disk properties across all three regions, when assuming compact disks with a declining magnetic field over time. In contrast, turbulent-driven models overestimate gas masses of >1 Myr disks by an order of magnitude. Here, we discuss the program’s motivation, survey design, sample selection, observation and data calibration processes, and highlight the initial results.
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This content will become publicly available on July 31, 2026
The ALMA Survey of Gas Evolution of PROtoplanetary Disks (AGE-PRO). VI. Comparison of Dust Evolution Models to AGE-PRO Observations
Abstract The potential for planet formation of a circumstellar disk depends on the dust and gas reservoirs, which evolve as a function of the disk age. The Atacama Large Millimeter/submillimeter Array AGE-PRO Large Program has measured several disk properties across three star-forming regions of different ages, and in this study, we compare the observational results to dust evolution simulations. UsingDustPyfor the dust evolution, andRADMC-3Dfor the radiative transfer, we ran a large grid of models spanning stellar masses of 0.25, 0.50, 0.75, and 1.0M⊙, with different initial conditions, including: disk sizes, disk gas masses, and dust-to-gas ratio, and viscosity. Our models are performed assuming smooth, weakly, or strongly substructured disks, aiming to investigate if any observational trend can favor or exclude the presence of dust traps. The observed gas masses in the disks of the AGE-PRO sample are not reproducible with our models, which only consider viscous evolution with constantα, suggesting that additional physical mechanisms play a role in the evolution of the gas mass of disks. When comparing the dust continuum emission fluxes and sizes at 1.3 mm, we find that most of the disks in the AGE-PRO sample are consistent with simulations that have either weak or strong dust traps. The evolution of spectral index in the AGE-PRO sample is also suggestive of an unresolved population of dust traps. Future observations at high angular resolution are still needed to test several hypotheses that result from comparing the observations to our simulations, including that more massive disks in gas mass have the potential to form dust traps at larger disk radii.
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- Award ID(s):
- 2205617
- PAR ID:
- 10646928
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- The Astrophysical Journal
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 989
- Issue:
- 1
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 6
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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