compute_flux_doubling

gammapy.stats.compute_flux_doubling(flux, flux_err, coords, axis=0)

Compute the minimum characteristic flux doubling and halving over a certain coordinate axis for a series of measurements.

Computing the flux doubling can give the doubling time in a lightcurve displaying significant temporal variability, e.g. an AGN flare.

The variable is computed as:

\[doubling = min \left( \frac{t_{(i+1)}-t_{i}}{log_2{f_{(i+1)}/f_{i}}} \right)\]

where \(f_i\) and \(f_{(i+1)}\) are the fluxes measured at subsequent coordinates \(t_i\) and \(t_{(i+1)}\). The error is obtained by propagating the relative errors on the flux measures.

Parameters:

fluxQuantity

The measured fluxes.

flux_errQuantity

The error on measured fluxes.

coordsQuantity

The coordinates at which the fluxes are measured.

axisint, optional

Axis along which the value is computed.

Returns:

doubling_dictdict

Dictionary containing the characteristic flux doubling, halving and errors, with coordinates at which they were found.