read_earthpoints

gdt.missions.fermi.gbm.localization.dol.legacy_functions.read_earthpoints(geodir, nai_unit_vec, back_unit_vec, scat_geom, path='/home/docs/checkouts/readthedocs.org/user_builds/astro-gdt-fermi/checkouts/latest/src/gdt/missions/fermi/gbm/localization/dol/data/earth_points.npy')[source]

Read array of position vectors used to compute scattering of photons off Earth’s atmosphere.

NOTE: This method can read from newer numpy files and older text files.

Parameters:

  • geodir (np.ndarray(3, np.float64)) – Vector pointing from spacecraft to center of the Earth

  • nai_unit_vec (np.ndarray(12, float32)) – Unit vectors along the direction of each NaI detector on spacecraft

  • back_unit_vec (np.ndarray(12, float32)) – Unit vector along the anti-direction of each NaI detector on spacecraft

  • scat_geom (int32) – Scattering geometry. 0=forward, 1=backward.

Returns:

  • earthpoints (np.ndarray((3,236), float32)) – Array of position vectors relative to the Earth that were used to build atmospheric scattering matrix obtained with read_scatter_data()

  • gperp (np.ndarray(3, 12), float32)) – Direction perpendicular to line between Earth center and each NaI detector

  • gpmag (np.ndarray(12, float32)) – Magnitude of each gperp vector

  • elev (np.ndarray(12, float32)) – Elevation angle for each detector in radians