Moddump recipes

This page lists common tasks that modify an existing Phantom dump file using built-in modules in src/utils/. For the generic moddump workflow (.in file handling, writing your own module), see Modifying phantom dump files.

Compile a specific module from your run directory (with a local Makefile from ~/phantom/scripts/writemake.sh):

make moddump MODFILE=moddump_addflyby.f90

Run in the same directory as the input ``.in`` file (see Modifying phantom dump files):

./phantommoddump dump_in dump_out [time]

Add a flyby to an evolved disc

Use this when you already have a relaxed or partially evolved disc and want to add an unbound perturber on a parabolic orbit (eccentricity = 1), without rebuilding the initial conditions from scratch.

This differs from a flyby set up at t=0 via phantomsetup, which creates both sinks and the disc together.

Module: moddump_addflyby.f90

cd ~/runs/mydisc
make moddump MODFILE=moddump_addflyby.f90
./phantommoddump relax_00150 flyby_00000 0.

You will be prompted for:

mass and accretion radius of the perturber
distance of minimum approach dma
initial distance in units of dma (n0; typically \(\gg 1\))
orbit orientation (ascending node angle, inclination)
suggested time between dumps as a fraction of the flyby time

The module reads the primary sink mass from the dump, recentres the system, and prints a suggested dtmax (in code units) for the output flyby.in. Edit flyby.in as needed, then run:

./phantom flyby.in

Orbital element conventions are described in Setting up orbits in phantom.

Add dust after gas relaxation

Module: moddump_dustadd.f90

Used in the dust settling test: relax a gas-only disc, then add dust particles before the science run.

make moddump MODFILE=moddump_dustadd.f90
./phantommoddump relax_00150 disc_00000 0.

Extend a disc in radius

Module: moddump_extenddisc.f90

Extends an existing disc outward, assuming the same surface density profile.

make moddump MODFILE=moddump_extenddisc.f90
./phantommoddump disc_00100 disc_extended_00000 0.

Add sinks or planets

Module	Purpose
`moddump_addsink`	Add a sink particle (interactive)
`moddump_addplanets`	Add embedded planets in a disc
`moddump_sinkbinary`	Add a binary sink pair
`moddump_binary`	Convert single star to binary
`moddump_binarystar`	Split relaxed star into binary components

Trim or edit the particle distribution

Module	Purpose
`moddump_removeparticles_radius`	Remove particles inside or outside a sphere
`moddump_removeparticles_cylinder`	Remove particles outside a cylinder
`moddump_recenter` / `moddump_CoM`	Recentre on centre of mass
`moddump_faceon`	Realign disc face-on, move origin
`moddump_rescale`	Change code units of the dump
`moddump_changemass`	Change particle masses
`moddump_disc`	Disc warp and magnetic field

Change resolution

Use the standalone binaries (or the moddump wrappers that call the same logic):

make splitpart
./splitpart dump_00000 dump_hi_00000

make mergepart
./mergepart dump_00000 dump_lo_00000

Import external dumps

Module	Purpose
`moddump_sphNG2phantom`	Import sphNG dump
`moddump_sphNG2phantom_disc`	sphNG disc with sinks
`moddump_sphNG2phantom_addBfield`	Import and add B-field

Inject particles from another simulation

See inject_sim for the inject_sim moddump module and the associated .in options (start_dump, final_dump, r_inject).

Other useful moddumps

Module	Purpose
`moddump_sink`	Edit sink properties interactively
`moddump_sink2gas`	Replace sinks with resolved gas
`moddump_growthtomultigrain`	Convert dust-growth dump for MCFOST
`moddump_LTE_to_rad` / `moddump_rad_to_LTE`	Switch radiation mode
`moddump_infall`	Add infalling cloud
`moddump_rotate`	Solid-body rotation on a sphere

A full list of modules is in src/utils/moddump_*.f90. To compile every moddump for testing:

make allmoddumps

Post-processing with phantomanalysis

To analyse dumps without modifying them, use phantomanalysis with a built-in analysis_* module (see Analysis of Phantom output). Common disc examples:

Module	Purpose
`analysis_disc`	Azimuthally averaged disc profiles
`analysis_dustydisc`	Disc analysis for `dustydisc` setups
`analysis_disc_planet`	Disc with embedded planet
`analysis_disc_stresses`	Stresses and alpha

make analysis ANALYSIS=analysis_disc.f90
./phantomanalysis dump_00100

Appendix: built-in module index

All moddump plugins live in src/utils/ as moddump_*.f90. All analysis plugins live as analysis_*.f90. Read the module header in each file for details. To compile a specific analysis module:

make analysis ANALYSIS=analysis_dustydisc.f90

moddump modules: moddump_addflyby, moddump_addplanets, moddump_addsink, moddump_binary, moddump_binarystar, moddump_changemass, moddump_CoM, moddump_disc, moddump_dustadd, moddump_dustsinkfrac, moddump_extenddisc, moddump_faceon, moddump_growthtomultigrain, moddump_infall, moddump_LTE_to_rad, moddump_mergepart, moddump_messupSPH, moddump_perturbgas, moddump_polytrope, moddump_radiotde, moddump_rad_to_LTE, moddump_recalcuT, moddump_recenter, moddump_removeparticles_cylinder, moddump_removeparticles_radius, moddump_rescale, moddump_rotate, moddump_sink, moddump_sink2gas, moddump_sinkbinary, moddump_splitpart, moddump_sphNG2phantom, moddump_sphNG2phantom_addBfield, moddump_sphNG2phantom_disc, moddump_taylorgreen, moddump_tdesink, moddump_temp, moddump_tidal, moddump_torus, plus moddump_default (template).

analysis modules (selection): analysis_disc, analysis_dustydisc, analysis_disc_planet, analysis_disc_stresses, analysis_disc_mag, analysis_disc_MFlow, analysis_dustmass, analysis_energies, analysis_angmom, analysis_ptmass, analysis_structurefn, analysis_clumpfind, analysis_mcfost, analysis_tde — and others in src/utils/analysis_*.f90.