bilby.gw.detector.geometry.InterferometerGeometry

class bilby.gw.detector.geometry.InterferometerGeometry(length, latitude, longitude, elevation, xarm_azimuth, yarm_azimuth, xarm_tilt=0.0, yarm_tilt=0.0)[source]

Bases: object

__init__(length, latitude, longitude, elevation, xarm_azimuth, yarm_azimuth, xarm_tilt=0.0, yarm_tilt=0.0)[source]

Instantiate an Interferometer object.

Parameters:

length: float: Length of the interferometer in km.
latitude: float: Latitude North in degrees (South is negative).
longitude: float: Longitude East in degrees (West is negative).
elevation: float: Height above surface in metres.
xarm_azimuth: float: Orientation of the x arm in degrees North of East.
yarm_azimuth: float: Orientation of the y arm in degrees North of East.
xarm_tilt: float, optional: Tilt of the x arm in radians above the horizontal defined by ellipsoid earth model in LIGO-T980044-08.
yarm_tilt: float, optional: Tilt of the y arm in radians above the horizontal.

__call__(*args, **kwargs): Call self as a function.

Methods

`__init__`(length, latitude, longitude, ...[, ...])	Instantiate an Interferometer object.
`unit_vector_along_arm`(arm)	Calculate the unit vector pointing along the specified arm in cartesian Earth-based coordinates.

Attributes

`detector_tensor`	Calculate the detector tensor from the unit vectors along each arm of the detector.
`elevation`	Updates related quantities if set to a different values.
`latitude`	Saves latitude in rad internally.
`latitude_radians`	Returns:
`longitude`	Saves longitude in rad internally.
`longitude_radians`	Returns:
`vertex`	Position of the IFO vertex in geocentric coordinates in meters.
`x`	A unit vector along the x-arm
`xarm_azimuth`	Saves the x-arm azimuth in rad internally.
`xarm_tilt`	Updates related quantities if set to a different values.
`y`	A unit vector along the y-arm
`yarm_azimuth`	Saves the y-arm azimuth in rad internally.
`yarm_tilt`	Updates related quantities if set to a different values.

property detector_tensor

Calculate the detector tensor from the unit vectors along each arm of the detector.

See Eq. B6 of arXiv:gr-qc/0008066

Is automatically updated if related quantities are modified.

Returns:

array_like: A 3x3 array representation of the detector tensor

property elevation

Updates related quantities if set to a different values.

Returns:

float: The height about the surface in meters

property latitude

Saves latitude in rad internally. Updates related quantities if set to a different value.

Returns:

float: The latitude position of the detector in degree

property latitude_radians

Returns:

float: The latitude position of the detector in radians

property longitude

Saves longitude in rad internally. Updates related quantities if set to a different value.

Returns:

float: The longitude position of the detector in degree

property longitude_radians

Returns:

float: The latitude position of the detector in radians

unit_vector_along_arm(arm)[source]

Calculate the unit vector pointing along the specified arm in cartesian Earth-based coordinates.

See Eqs. B14-B17 in arXiv:gr-qc/0008066

Parameters:

arm: str: ‘x’ or ‘y’ (arm of the detector)

Returns:

array_like: 3D unit vector along arm in cartesian Earth-based coordinates

Raises:

ValueError: If arm is neither ‘x’ nor ‘y’

property vertex

Position of the IFO vertex in geocentric coordinates in meters.

Is automatically updated if related quantities are modified.

Returns:

array_like: A 3D array representation of the vertex

property x

A unit vector along the x-arm

Is automatically updated if related quantities are modified.

Returns:

array_like: A 3D array representation of a unit vector along the x-arm

property xarm_azimuth

Saves the x-arm azimuth in rad internally. Updates related quantities if set to a different values.

Returns:

float: The x-arm azimuth in degrees.

property xarm_tilt

Updates related quantities if set to a different values.

Returns:

float: The x-arm tilt in radians.

property y

A unit vector along the y-arm

Is automatically updated if related quantities are modified.

Returns:

array_like: A 3D array representation of a unit vector along the y-arm

property yarm_azimuth

Saves the y-arm azimuth in rad internally. Updates related quantities if set to a different values.

Returns:

float: The y-arm azimuth in degrees.

property yarm_tilt

Updates related quantities if set to a different values.

Returns:

float: The y-arm tilt in radians.