Open Access
Table 3
Parameter definitions.
Symbol | Definition/value | Description |
---|---|---|
r | Normalised radius at 1 AU | |
σ | Gas surface-density | |
P | Vertically integrated pressure | |
T | ![]() |
Gas temperature |
v | Gas velocity-field | |
v′ | v − ΩK reθ | Relative gas-velocity (with respect to the angular gas velocity) |
Φ⊙ | Central object potential | |
ΦSG | Gas SG potential | |
Φind | Indirect potential (offset of Φ⊙) | |
ΩK | ![]() |
Pressure-supported rotation-rate |
γ | 1.4 | Adiabatic index |
cs | ![]() |
Gas sound-speed |
H | ![]() |
Pressure scale-height |
h(r) | ![]() |
Disc aspect ratio |
Q | Ωkcs/(πGσ) | Local Toomre’s parameter |
Q0 | Ωkcs/(πGσ0) | Toomre’s parameter at 50 AU for the Axis-symmetric disc |
Qc | 1/h = 20 | Critical Toomre parameter |
q0 | Q0/Qc | SG parameter |
Ro | ∇ × v′/2Ωk | Rossby number |
![]() |
〈Ro〉core | Vortex spin |
χ | Vortex aspect-ratio | |
Δr | Vortex radial-width | |
δ | Δr/H | Vortex radial-extent |
t0 | 353 yr | Orbital period at 50 AU |
Cσ | σ/σ0 − 1 | Density contrast |
CP | P/P0 − 1 | Pressure contrast |
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