Some notes on conventions ========================= Coordinates ----------- Default coordinate system _________________________ NuRadioMC uses a local cartesian coordinate system. The origin is at the surface, where the x axis is towards Easting, the y axis towards Northing, and the z axis upwards. Points ______ All points (e.g. antenna positions) are specified with respect to the coordinate origin. The position (0,0,0) is at the surface and x = 0, y = 0 is typically at the center of the station. Angles ______ The zenith/theta angle is defined with respect to z axis, i.e. * 0 deg = upwards * 90deg = towards horizon * 180 deg = downwards. The azimuth/phi angle is counting northwards from East. Directions __________ All direction are pointing to "where it came from", i.e. opposite to the direction of propagation. E.g. * 0 deg zenith angle = coming from above = propagating downwards * 180 deg zenith angle = coming from below = propagating upwards (through the Earth) Exception: The ``launch_vector``, the direction to which the Askaryan signal is emitted to reach the antenna, is defined into the direction of propagation. Units ----- Physical quantities in ``NuRadioMC`` use Auger base units. To print, plot and convert dimensional quantities, a convenient module is included in ``NuRadioReco``. Details are given :ref:`here `. Particle types -------------- Particle types are encoded using the `PDG convention `_. The most relevant particle ids for us are [12,14,16] for the electron, muon and tau neutrino, respectively, with an overall minus sign indicating their corresponding anti-particles. A more extensive overview is included as a table in the :ref:`event generation manual `. Fourier transformations ----------------------- To ensure Fourier transforms have the correct units, please use the convenience functions provided in NuRadioReco detailed :ref:`here `.