coordinatesystems

class coordinatesystems.cstrafo(zenith, azimuth, magnetic_field_vector=None, site=None)

class to performe coordinate transformations typically used in air shower radio detection

the following transformations are implemented:

From the cartesian ground coordinate system (x: East, y: North, z: up) to

• to the vxB-vx(vxB) system
• to the on-sky coordinate system (spherical coordinates eR, eTheta, ePhi)
• to a ground coordinate system where the y-axis is oriented to magnetic North (instead of geographic North)

and vice versa.

__init__(zenith, azimuth, magnetic_field_vector=None, site=None)

Initialization with signal/air-shower direction and magnetic field configuration.

All parameters should be specified according to the default coordinate system of the radiotools package (the Auger coordinate system).

Parameters:

• zenith (float) – zenith angle of the incoming signal/air-shower direction (0 deg is pointing to the zenith)
• azimuth (float) – azimuth angle of the incoming signal/air-shower direction (0 deg is North, 90 deg is South)
• (optional) (site) – the magnetic field vector in the cartesian ground coordinate system, if no magnetic field vector is specified, the default value for the site specified in the ‘site’ function argument is used.
• (optional) – this argument has only effect it ‘magnetic_field_vector’ is None the site for which the magnetic field vector should be used. Currently, default values for for the sites ‘auger’ and ‘arianna’ are available

transform_from_ground_to_onsky(positions)

on sky coordinates are eR, eTheta, ePhi

transform_from_onsky_to_ground(positions)

on sky coordinates are eR, eTheta, ePhi

transform_from_magnetic_to_geographic(positions)

transform_from_magnetic_to_geographic2(positions)

transform_from_geographic_to_magnetic(positions)

transform_to_vxB_vxvxB(station_position, core=None)

transform a single station position or a list of multiple station positions into vxB, vxvxB shower plane

This function is supposed to transform time traces with the shape (number of polarizations, length of trace) and a list of station positions with the shape of (length of list, 3). The function automatically differentiates between the two cases by checking the length of the second dimension. If this dimension is ‘3’, a list of station positions is assumed to be the input. Note: this logic will fail if a trace will have a shape of (3, 3), which is however unlikely to happen.

transform_from_vxB_vxvxB(station_position, core=None)

transform a single station position or a list of multiple station positions back to x,y,z CS

This function is supposed to transform time traces with the shape (number of polarizations, length of trace) and a list of station positions with the shape of (length of list, 3). The function automatically differentiates between the two cases by checking the length of the second dimension. If this dimension is ‘3’, a list of station positions is assumed to be the input. Note: this logic will fail if a trace will have a shape of (3, 3), which is however unlikely to happen.

__module__ = 'coordinatesystems'

transform_from_vxB_vxvxB_2D(station_position, core=None)

transform a single station position or a list of multiple station positions back to x,y,z CS

get_height_in_showerplane(x, y)

get_euler_angles()