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Trajectory

Trajectory Diagram

OTSO.trajectory

trajectory(Stations: Union[str, Sequence[str]], customlocations: Optional[list] = None, solar_wind: SolarWindParams = {}, geomagnetic: GeomagneticParams = {}, tsyganenko: TsyganenkoParams = {}, datetime_params: DateTimeParams = {}, magfield_params: MagFieldParams = {}, integration_params: IntegrationParams = {}, particle_params: ParticleParams = {}, coordinate_params: CoordinateParams = {}, computation_params: ComputationParams = {}, data_retrieval_params: DataRetrievalParams = {}, custom_field_params: CustomFieldParams = {}, rigidity_params: RigidityParams = {}, *args, **kwargs)

Compute cosmic-ray particle trajectories using the OTSO framework.

Traces individual particles through the magnetosphere to determine their trajectories from given starting locations and rigidity.

Parameters:

  • Stations (str | list) –

    Station name(s) or identifiers for trajectory calculations.

  • customlocations (list, default: None ) –

    Custom locations as [["NAME", lat, lon]].

  • datetime_params (DateTimeParams, default: {} ) –

    Date/time parameters.

    Available keys:

    • year (int, default=2024): Year (e.g., 2023)
    • month (int, default=1): Month (1–12)
    • day (int, default=1): Day (1–31)
    • hour (int, default=12): Hour (0–23)
    • minute (int, default=0): Minute (0–59)
    • second (int, default=0): Second (0–59)
  • magfield_params (MagFieldParams, default: {} ) –

    Magnetic field models.

    Available keys:

    • internalmag (str, default="IGRF"): "NONE", "IGRF", "Dipole", "Custom Gauss"
    • externalmag (str, default="TSY89c"): "NONE", "TSY89c", "TSY01", "TSY15B", etc.
    • boberg (bool, default=False): Enable Boberg extension
    • bobergtype (str, default="EXTENSION"): Boberg extension type
    • magnetopause (str, default="Kobel"): "NONE", "Kobel", "Sibeck", "Lin", "Sphere"
    • spheresize (float, default=25): Spherical boundary radius (Re)
    • AdaptiveExternalModel (bool, default=False): Auto-select external model
  • rigidity_params (RigidityParams, default: {} ) –

    Rigidity scanning.

    Available keys:

    • startrigidity (float, default=20): Initial rigidity (GV)
    • endrigidity (float, default=0): Final rigidity (GV)
    • rigiditystep (float, default=0.01): Step size (GV)
    • rigidityscan (str, default="ON"): Enable scanning ("ON"/"OFF")
  • solar_wind (SolarWindParams, default: {} ) –

    Solar wind parameters.

    Available keys:

    • vx (float, default=-500): Solar wind velocity x-component (km/s)
    • vy (float, default=0): Solar wind velocity y-component (km/s)
    • vz (float, default=0): Solar wind velocity z-component (km/s)
    • bx (float, default=0): IMF x-component (nT)
    • by (float, default=5): IMF y-component (nT)
    • bz (float, default=5): IMF z-component (nT)
    • by_avg (float, default=0): Averaged IMF By (nT)
    • bz_avg (float, default=0): Averaged IMF Bz (nT)
    • density (float, default=1): Solar wind density (particles/cm³)
    • pdyn (float, default=0): Solar wind dynamic pressure (nPa)
  • geomagnetic (GeomagneticParams, default: {} ) –

    Geomagnetic indices.

    Available keys:

    • Dst (float, default=0): Dst index (nT)
    • kp (float, default=0): Kp index (0-9)
    • n_index (float, default=0): Newell coupling function
    • b_index (float, default=0): Boynton coupling function
    • sym_h_corrected (float, default=0): Corrected SYM-H index (nT)
  • tsyganenko (TsyganenkoParams, default: {} ) –

    Tsyganenko model coefficients.

    Available keys:

    • G1 (float, default=0): Tsyganenko G1 coefficient
    • G2 (float, default=0): Tsyganenko G2 coefficient
    • G3 (float, default=0): Tsyganenko G3 coefficient
    • W1 (float, default=0): Tsyganenko W1 coefficient
    • W2 (float, default=0): Tsyganenko W2 coefficient
    • W3 (float, default=0): Tsyganenko W3 coefficient
    • W4 (float, default=0): Tsyganenko W4 coefficient
    • W5 (float, default=0): Tsyganenko W5 coefficient
    • W6 (float, default=0): Tsyganenko W6 coefficient
  • integration_params (IntegrationParams, default: {} ) –

    Integration settings.

    Available keys:

    • intmodel (str, default="Boris"): "Boris", "4RK", "Vay", "HC"
    • gyropercent (float, default=15): Gyration period percentage
    • minaltitude (float, default=20): Minimum altitude (GDZ = km or other = Re)
    • maxdistance (float, default=100): Maximum distance (Re)
    • maxtime (float, default=0): Maximum time
    • mintrapdist (float, default=0): Minimum trapping distance
    • startaltitude (float, default=20): Starting altitude (GDZ = km or other = Re)
    • betaerror (float, default=0.001): Maximum allowed beta error for integration steps %
    • totalbetacheck (bool, default=False): Enable cumulative beta check during integration
    • adaptivestep (bool, default=True): Enable adaptive time steps
    • maxsteps (int, default=None): Maximum number of integration steps
  • particle_params (ParticleParams, default: {} ) –

    Particle settings.

    Available keys:

    • Anum (int, default=1): Atomic number (0=electron, 1=proton, 2=alpha)
    • anti (str, default="YES"): YES = anti-particle, NO = particle
    • zenith (float, default=0): Launch zenith angle
    • azimuth (float, default=0): Launch azimuth angle
  • coordinate_params (CoordinateParams, default: {} ) –

    Coordinate systems.

    Available keys:

    • coordsystem (str, default="GEO"): Coordinate system used for calculations
    • inputcoord (str, default="GDZ"): Input coordinate system
  • computation_params (ComputationParams, default: {} ) –

    Computation settings.

    Available keys:

    • corenum (int, default=None): Number of CPU cores for multicore processing
    • Verbose (bool, default=True): Enable verbose output
  • data_retrieval_params (DataRetrievalParams, default: {} ) –

    Data retrieval.

    Available keys:

    • serverdata (str, default="OFF"): Server data retrieval from OMNI
    • livedata (str, default="OFF"): real-time data retrieval from NOAA
  • custom_field_params (CustomFieldParams, default: {} ) –

    Custom fields.

    Available keys:

    • g (list, default=None): Gauss g coefficients
    • h (list, default=None): Gauss h coefficients
    • MHDfile (str, default=None): MHD simulation file
    • MHDcoordsys (str, default=None): MHD coordinate system

Returns:

  • list

    [trajectory_data, summary_text] - trajectory_data: Dictionary with positional information for trajectories - summary_text: Input parameter summary

Examples:

    import OTSO

    # Single particle trajectory
    traj_result = OTSO.trajectory(["OULU"], 
                                 rigidity_params={"startrigidity": 5.0},
                                 computation_params={"corenum": 2})

    # With specific magnetic field conditions
    traj_data = OTSO.trajectory(["DOMC"], 
                               rigidity_params={"startrigidity": 10.0},
                               datetime_params={"year": 2023, "month": 3},
                               magfield_params={"externalmag": "TSY01"})

    # Access the results
    trajectory_dict, metadata = traj_result