Quasi-normal mode functions

gwmemory.qnms.final_mass_spin(mass_1: float, mass_2: float) → Tuple[float, float]

Given initial total mass and mass ratio, calculate the final mass, M_f and dimensionless spin parameter, jj, using fits in Buonanno et al. (2007) – see the caption of their Table I.

Parameters:

mass_1: float

Mass of more massive black hole.

mass_2: float

Mass of less massive black hole.

Returns:

final_mass: float

Remnant mass

jj: float

Remnant dimensionless spin

gwmemory.qnms.freq_damping(mass: float, spin: float, nn: int = 0) → Tuple[float, float]

Calculate the quasinormal mode freq and damping time for a black hole. This version uses OBSERVER’S UNITS.

The magic numbers come from https://pages.jh.edu/eberti2/ringdown/fitcoeffsWEB.dat

Parameters:

mass: float

BH mass in solar masses

spin: float

BH dimensionless spin

nn: int, optional

QNM harmonic, default=0 is the fundamental

Returns:

omega_lmn: float

Angular frequency of mode in geometric units

tau_lmn: float

Damping time of mode in geometric units