pint.derived_quantities.dth
- pint.derived_quantities.dth(mp: Unit('solMass'), mc: Unit('solMass'), pb: Unit('d'))[source]
Post-Keplerian Roemer delay term
dth (\(\delta_{\theta}\)) is part of the relativistic deformation of the orbit
- Parameters:
mp (astropy.units.Quantity) – pulsar mass
mc (astropy.units.Quantity) – companion mass
pb (astropy.units.Quantity) – Binary orbital period
- Returns:
dth
- Return type:
- Raises:
astropy.units.UnitsError – If the input data are not appropriate quantities
TypeError – If the input data are not quantities
Notes
Calculates
\[\delta_{\theta} = T_{\odot}^{2/3} \left(\frac{P_b}{2\pi}\right)^{2/3} \frac{3.5 m_p^2+6 m_p m_c +2m_c^2}{(m_p+m_c)^{4/3}}\]with \(T_\odot = GM_\odot c^{-3}\).
More details in Timing Models. Also see [13].