pint.fermi_toas.get_Fermi_TOAs

pint.fermi_toas.get_Fermi_TOAs(ft1name, weightcolumn=None, targetcoord=None, logeref=4.1, logesig=0.5, minweight=0.0, minmjd=-inf, maxmjd=inf, fermiobs='Fermi', ephem=None, planets=False, include_bipm=False, errors=<Quantity 1. us>)[source]

Read photon event times out of a Fermi FT1 file and return a pint.toa.TOAs object

Correctly handles raw FT1 files, or ones processed with gtbary to have barycentered or geocentered TOAs.

Parameters:

  • weightcolumn (str) – Specifies the FITS column name to read the photon weights from. The special value CALC causes the weights to be computed empirically as in Philippe Bruel’s SearchPulsation code.

  • targetcoord (astropy.coordinates.SkyCoord) – Source coordinate for weight computation if weightcolumn==’CALC’

  • logeref (float) – Parameter for the weight computation if weightcolumn==’CALC’

  • logesig (float) – Parameter for the weight computation if weightcolumn==’CALC’

  • minweight (float) – If weights are loaded or computed, exclude events with smaller weights.

  • minmjd (float) – Events with earlier MJDs are excluded.

  • maxmjd (float) – Events with later MJDs are excluded.

  • fermiobs (str) – The default observatory name is Fermi, and must have already been registered. The user can specify another name

  • ephem (str, optional) – The name of the solar system ephemeris to use; defaults to “DE421”.

  • planets (bool, optional) – Whether to apply Shapiro delays based on planet positions. Note that a long-standing TEMPO2 bug in this feature went unnoticed for years. Defaults to False.

  • include_bipm (bool, optional) – Use TT(BIPM) instead of TT(TAI)

  • errors (astropy.units.Quantity or float, optional) – The uncertainty on the TOA; if it’s a float it is assumed to be in microseconds

Return type:

pint.toa.TOAs

Examples

To create a pint.toa.TOAs object, you need an event file and a spacecraft orbit file (called ft2file):

>>> import pint.toa as toa
>>> from pint.fermi_toas import get_Fermi_TOAs
>>> from pint.observatory.satellite_obs import get_satellite_observatory
>>> get_satellite_observatory("Fermi", ft2file, overwrite=True)
>>> toas = get_Fermi_TOAs(eventfile, weightcolumn="PSRJ0030+0451", ephem="DE405")