gw.transforms.detector_transforms.time_delay_from_geocenter

gw.transforms.detector_transforms.time_delay_from_geocenter(ifo, ra, dec, time)

Calculate time delay between ifo and geocenter. Identical to method ifo.time_delay_from_geocenter(ra, dec, time), but the present implementation allows for batched computation, i.e., it also accepts arrays and tensors for ra and dec.

Implementation analogous to bilby-cython implementation https://git.ligo.org/colm.talbot/bilby-cython/-/blob/main/bilby_cython/geometry.pyx, which is in turn based on XLALArrivaTimeDiff in TimeDelay.c.

Parameters

Name Type Description Default
ifo Interferometer bilby interferometer object. required
ra Union[float, np.ndarray, torch.Tensor] Right ascension of the source in radians. Either float, or float array/tensor. required
dec Union[float, np.ndarray, torch.Tensor] Declination of the source in radians. Either float, or float array/tensor. required
time float GPS time in the geocentric frame. required

Returns

Name Type Description
float Time delay between the two detectors in the geocentric frame