pint.fermi_toas.calc_lat_weights

pint.fermi_toas.calc_lat_weights(energies, angseps, logeref=4.1, logesig=0.5)[source]

Compute photon weights based on PSF.

This function computes photon weights based on the energy-dependent PSF, as defined in Philippe Bruel’s SearchPulsation code. It was built by David Smith, based on some code from Lucas Guillemot. This computation uses only the PSF as a function of energy, not a full spectral model of the region, so is less exact than gtsrcprob.

Parameters:

  • energies (np.array) – Array of photon energies in MeV

  • angseps (array of astropy Angles) – Angular separations between photon direction and target This should be astropy Angle array, such as returned from SkyCoord_photons.separation(SkyCoord_target)

  • logeref (Parameter) – from SearchPulsation optimization

  • logesig (Parameter) – from SearchPulsation optimization

Returns:

weights (probabilities that the photons came from the target, based on the PSF).

Return type:

np.array