detectabilityfuns

This is the documentation for the detectabilityfuns module, which consists of parts of the procedure for calculating the detectability fraction of a merger given its optimal-alignment SNR, collected into modular functions.

cdf_generator

cdf_generator(N=10**6)

Generates the cumulative distribution function (CDF) of the projection function Theta, for use with detectability_calculator(), based on Finn (1996), Belczynski et al. (2013), Belczynski et al. (2014).

Parameters

N: int

The number of random samples of Theta you want to take to build the CDF. Default: 10**6.

Returns

Theta_CDF: function

The CDF of the projection function Theta.

min_CDF: float

The lower boundary of the range over which Theta_CDF is defined.

max_CDF: float

The upper boundary of the range over which Theta_CDF is defined.

detectability_calculator

detectability_calculator(Theta_CDF,min_CDF,max_CDF,SNR_in)

Given the optimal-alignment SNR of a merger, this function returns the fraction of arbitrary orientations in which the merger would be expected to be observable (i.e. have a SNR above 8).

Parameters

Theta_CDF: function

The CDF of the projection function Theta, from cdf_generator().

min_CDF: float

The lower boundary of the range over which Theta_CDF is defined, from cdf_generator().

max_CDF: float

The upper boundary of the range over which Theta_CDF is defined, from cdf_generator().

SNR_in: float

The optimal-alignment SNR of the merger in question, can be obtained from snrcalculatorfuns.

Returns

det: float

The detectability fraction of the merger.

specific_orientation_SNR

specific_orientation_SNR(theta,phi,iota,psi,SNR_in,angle_unit='rad')

Given the optimal-alignment SNR of a merger, this function returns the SNR that would result if the detector and binary had a specific orientation/ alignment, specified by four angles as in Finn (1996), Belczynski et al. (2013), Belczynski et al. (2014).

Parameters

theta: float

The relative latitude, one of the angles describing the direction of the line of sight to the gravitational wave source relative to the axes of the detector’s arms (sky-location coordinates of the binary). Ranges from 0 to π rad (180 deg).

phi: float

The relative longitude, one of the angles describing the direction of the line of sight to the gravitational wave source relative to the axes of the detector’s arms (sky-location coordinates of the binary). Ranges from 0 to 2π rad (360 deg).

iota: float

The inclination angle of the binary. Ranges from 0 to π rad (180 deg).

psi: float

The polarisation angle of the binary. Ranges from 0 to π (180 deg).

SNR_in: float

The optimal-alignment SNR of the merger in question, can be obtained from snrcalculatorfuns.

angle_unit: str

Specifies whether the input angles are given in ‘rad’ or ‘deg’; the default is ‘rad’.

Returns

SNR_out: float

The SNR of the merger in question at the specific orientation given by the input angles.