Erglog definition

[gabriele-panebianco-inaf]

Check the definition of "erglog", which is probably the nuFnu at a reference energy or the energy flux in a given bin.

Update using the GADF definitions: https://gamma-astro-data-formats.readthedocs.io/en/v0.3/

• dNdE: differential photon flux in ph s-1 cm-2 MeV-1. This is the evaluation of a spectral model function (e.g. a power law), and it is always evaluated at an input energy: dNdE(E) = something ph s-1 cm-2 MeV-1.
• E2 dNdE: differential energy flux in erg s-1 cm-2. This is also known as the nu F_nu. It is given by E2 * dNdE. It is always evaluated at an input energy. E.g. for a power law with index 2, it is a constant function. It can be plotted in a SED as a continuous function
• Photon flux (or flux) in ph s-1 cm-2. Integral of dNdE in a given energy range. It is always integrated in a band (or computed above a given energy, e.g. >100 MeV, assuming the upper energy tends to infitinity). It is given by \integral_E1^E2 (dNdE) dE
• Energy flux (or eflux) in erg s-1 cm-2. Not be confused with the nu F_nu, it is an integrated value in an energy band. It is given by \integral_E1^E2 (E dNdE) dE. It can be plotted in a SED as a value integrated in a band. The luminosity is given by eflux * 4\piD_L^2...