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Settings and inputs

The TOML settings file

The command line reads one TOML file (morrigan -c <file>). Units at this boundary are Earth masses, au, degrees, and Gyr; everything is converted once on read and the model runs in SI.

[run_simulation]

Setting Meaning Units
t, t_ref, t_event Initial clock, secular reference epoch, and first event time; all zero for a fresh run s
flag_event 1 to compute the secular solution and first crossing at start; leave at 1 -
a_min Perihelion inside which a body has fallen into the star au
max_time Length of the dynamical evolution Gyr
random_seed Base seed for the batch; each system's seed is mixed from this and the system index -
save_directory Where result tables are written; relative paths resolve from the working directory -

[init_par]

Setting Meaning Units
N Number of embryos -
e Initial eccentricity shared by all embryos -
impact_angle Impact angle for every collision; its sine is the impact parameter deg
Mp Embryo masses, one per embryo Earth masses
Ms Stellar mass solar masses
rho_p Bulk density shared by all embryos kg m-3
inner_edge Orbit of the innermost embryo au
spacing Spacing between adjacent embryos mutual Hill radii

[batch] (optional)

Setting Meaning
ndisk Number of systems to run (default 1)
nproc Worker processes for a batch (default: cores minus one)

The in-memory entry point

morrigan.run_system(seed, masses, eccentricity, inner_edge, spacing, density, impact_angle, evolution_time, inner_cutoff, stellar_mass) takes SI inputs (kg, m) apart from the stellar mass in solar masses and the evolution time in Gyr, and returns survivors and per-impact records in SI with times in years. The record schema is documented in Coupling to PROTEUS.