Fermi Light Curve Repository Data Description

Source Report Table Description

Date: Mid point of time bin in UTC.
Julian date: Mid point of time bin in JD.
MET: Mid point of time bin in Mission Elapsed Time (MET).
TS: The likelihood Test Statistic.
Photon Flux: Average integrated photon flux with energies from 0.1 to 100 GeV. Units in photons/cm^2/s.
Photon Flux Error: 1-sigma symmetric gaussian equivalent statistical uncertainty based on the inverse-Hessian at the optimum of the log-likelihood surface. Units in photons/cm^2/s.
Energy Flux: Average integrated energy flux with energies from 0.1 to 100 GeV. Units in MeV/cm^2/s.
Energy Flux Error: 1-sigma symmetric gaussian equivalent statistical uncertainty based on the inverse-Hessian at the optimum of the log-likelihood surface. Units in MeV/cm^2/s.
Photon Index: Average photon index, if the spectral model for the source in the FGL catalog used by the LCR is a power-law. Average alpha, if the spectral model for the source in the FGL catalog used by the LCR is a logparabola.
Photon Index Error: 1-sigma symmetric gaussian equivalent photon index error
Fit Tolerance: Relative fit tolerance.
MINUIT Return Code: Anything other than '0' means that the analysis did not converge. Please read the caveats about non-convergent analyses.
Analysis Log: Complete LAT analysis runtime output of data within the time invertal of the bin.

JSON File Description

Some of the objects below are provided as arrays of 2-tuples where the first element is the center of the bin time interval (in MET).
ts: The likelihood Test Statistic.
flux: Average integrated flux of photons with energies from 0.1 to 100 MeV. Units in photons/cm^2/s if photon flux is selected, MeV/cm^2/s if energy flux is selected.
flux_upper_limits: 95% Flux upper limits in photons/cm^2/s.
flux_error: 1-sigma symmetric gaussian equivalent statistical uncertainty in photons/cm^2/s if photon flux is selected, MeV/cm^2/s if energy flux is selected.
photon_index: Photon index if source spectral shape is power-law, alpha if it is logparabola.
photon_index_error: 1-sigma symmetric gaussian equivalent photon index/alpha statistical uncertainty.
fit_tolerance: Relative fit tolerance.
fit_convergence: MINUIT return code. Anything other than '0' means that the analysis did not converge. Please read the caveats about non-convergent analyses.
dlogl: Delta log-likelihood between a fixed index and free index fit.
EG: Isotropic diffuse background Normalization.
GAL: Galactic diffuse background Prefactor.
bin_id: Time bin number.