The parameters are:
1) the relative flux amplitude,
2) the gaussian width (in arcsec)
3) the x- and
4) the y-position of the gaussian center relative to the map center (in arcsec)
5) the eccentricity for elliptical gaussians [e=ywidth/xwidth-1]
6) the tilt angle of elliptical gaussian (deg counterclockwise from x-axis)
7) curvature ratio, i.e. gaussian width/curvature radius