def half_light_radius_source(self, kwargs_source, center_x=0, center_y=0, deltaPix=None, numPix=None):
        """
        computes numerically the half-light-radius of the deflector light and the total photon flux

        :param kwargs_source:
        :return:
        """
        if numPix is None:
            numPix = 1000
        if deltaPix is None:
            deltaPix = 0.005
        x_grid, y_grid = util.make_grid(numPix=numPix, deltapix=deltaPix)
        x_grid += center_x
        y_grid += center_y
        source_light = self.SourceModel.surface_brightness(x_grid, y_grid, kwargs_source)
        R_h = analysis_util.half_light_radius(source_light, x_grid, y_grid, center_x=center_x, center_y=center_y)
        return R_h
computes numerically the half-light-radius of the deflector light and the total photon flux

        :param kwargs_source:
        :return: