Science Products & Timeseries Reference
Output Data Guide
Complete reference for Sailfish science products (2D fields) and timeseries (integrated quantities) outputs, including physical meanings and applications.
Science Products (2D Fields)
Science products are 2D spatial arrays saved to HDF5 files at intervals specified by spi. Each product represents a physical quantity distributed across the computational domain.
Available Products
| Column | Name | Symbol | Units | Description |
|---|---|---|---|---|
| 0 | mass_density | ρ | M L⁻² | Surface mass density of gas |
| 1 | x_velocity | vₓ | L T⁻¹ | Velocity component in x-direction |
| 2 | y_velocity | vᵧ | L T⁻¹ | Velocity component in y-direction |
| 3 | gas_pressure | P | M L⁻¹ T⁻² | Gas pressure (depends on thermodynamics) |
| 4 | gravitational_torque_density | τ | M L T⁻² | Gravitational torque density per unit area |
| 5 | x_vertices | x | L | x-coordinates of mesh vertices |
| 6 | y_vertices | y | L | y-coordinates of mesh vertices |
| 7 | M1_x | x₁ | L | x-position of primary mass |
| 8 | M1_y | y₁ | L | y-position of primary mass |
| 9 | M2_x | x₂ | L | x-position of secondary mass |
| 10 | M2_y | y₂ | L | y-position of secondary mass |
Timeseries Data
Timeseries are globally integrated quantities computed at intervals specified by tsi. Each timeseries represents a single scalar value characterizing the entire simulation domain.
Angular Momentum & Torques
| Column | Name | Symbol | Units | Description |
|---|---|---|---|---|
| 0 | Jdot_grav | J̇ₘᵣₐᵥ | M L² T⁻³ | Total gravitational torque on disk |
| 1 | Jdot_excised | J̇ₑₓc | M L² T⁻³ | Gravitational torque excluding inner region |
| 8 | Jdot_accrete | J̇ₐcc | M L² T⁻³ | Angular momentum loss to accretion |
| 9 | Jdot_spin | J̇ₛₚᵢₙ | M L² T⁻³ | Spin torque (not implemented) |
| 11 | Ldisk | L | M L² T⁻¹ | Total angular momentum of disk |
| 15 | Jdisk_excised | Lₑₓc | M L² T⁻¹ | Angular momentum excluding inner region |
Angular Momentum Budget
Conservation: dL/dt = J̇ₘᵣₐᵥ + J̇ₐcc + J̇ₛₚᵢₙ
Physical Interpretation:
Jdot_grav: Torque from binary gravitational fieldJdot_accrete: Angular momentum carried away by accreted materialJdot_excised: Excludes regions near binary (r < a)
Mass & Accretion
| Column | Name | Symbol | Units | Description |
|---|---|---|---|---|
| 6 | Mdot1 | Ṁ₁ | M T⁻¹ | Mass accretion rate onto primary |
| 7 | Mdot2 | Ṁ₂ | M T⁻¹ | Mass accretion rate onto secondary |
| 10 | Mdisk | M_disk | M | Total mass in disk |
| 12 | Mdot_buffer | Ṁ_buf | M T⁻¹ | Buffer zone mass flux (not implemented) |
| 14 | Mdisk_excised | M_exc | M | Disk mass excluding inner region |
| 21 | Mdot_inner_boundary | Ṁ_ᵢₙ | M T⁻¹ | Mass flux through inner boundary |
Momentum & Forces
| Column | Name | Symbol | Units | Description |
|---|---|---|---|---|
| 16 | Pdot_x_grav | Ṗₓ,ₘᵣₐᵥ | M L T⁻³ | x-momentum change from gravity |
| 17 | Pdot_y_grav | Ṗᵧ,ₘᵣₐᵥ | M L T⁻³ | y-momentum change from gravity |
| 18 | Pdot_x_accrete | Ṗₓ,ₐcc | M L T⁻³ | x-momentum loss to accretion |
| 19 | Pdot_y_accrete | Ṗᵧ,ₐcc | M L T⁻³ | y-momentum loss to accretion |
Momentum Budget
Forces: Gravitational and accretion forces on disk
Applications: Disk migration, orbital evolution feedback
Disk Structure Analysis
| Column | Name | Symbol | Units | Description |
|---|---|---|---|---|
| 2 | psi_re | ℜ(ψ) | M | Real part of m=1 density mode |
| 3 | psi_im | ℑ(ψ) | M | Imaginary part of m=1 density mode |
| 4 | ex | eₓ | - | x-component of eccentricity vector |
| 5 | ey | eᵧ | - | y-component of eccentricity vector |
Mode Analysis
m=1 Density Mode: ψ = ∫ ρ e^(iφ) dA
Eccentricity Vector: e⃗ = (1/M_nominal) ∫ ρ e⃗_orbital dA
Applications: Disk precession, spiral wave tracking, asymmetry detection
Time Coordinate
| Column | Name | Symbol | Units | Description |
|---|---|---|---|---|
| 20 | time | t | T | Simulation time in user units |
Time Conversion
User Time: t_user = t_raw / tunits
Orbital Periods: For tunits = -1, one orbit = 1 time unit
Diagnostic Set Configurations
Pre-defined Sets
Products: 0, 1, 2, 3, 4, 5, 6 (all available)
Timeseries: 0-21 (complete set)
Use: Development, comprehensive analysis
diagnostic_set = "custom"
sp = [0, 1, 2, 3] # Density + velocities + pressure
ts = [0, 10, 11, 20] # Torque + mass/momentum + time
Products: User-specified columns
Timeseries: User-specified columns
Use: Production runs, focused studies
Products: None defined (empty set)
Timeseries: None defined (empty set)
Use: Performance testing, minimal I/O