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Table 1

Default disk and stellar parameters of TRAPPIST-1 during the planet formation phase.

Symbol Description Value Comments

α viscosity parameter inner disk 10-3 a
δ ice fractional width of iceline 0.05
γ I prefactor in type-I migration rate 4 b
ξ # e-foldings to reach pebble size 10
τ p pebble dimensionless stopping time exterior to iceline 0.05 c
ζ dust fraction in pebbles 0.5
h inner disk aspect ratio 0.03
r out outer disk radius 200 au
B stellar magnetic field strength at surface 180G
M stellar mass 0.08M
M disk disk mass (gas) 0.04M
g accretion rate 10-10Myr-1
R stellar radius 0.5R
Z 0 disk metallicity (global solids-to-gas mass ratio) 0.02



Our default model. We also discuss more laminar and more turbulent disks (10-4α ≤ 10-2);


the stopping time of pebbles interior to the iceline is denoted τs with τsτp.

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