A new beamline is now operational at LURE, on bending-magnet 7 of the Super
ACO storage ring in Orsay. The monochromator is of the 'dragon' type, desig
ned to work in the energy range 150-1500 eV, and is equipped with a double
vertical focusing mirror in order to allow for fast switching of light pola
rization. In this paper the results of photoion-yield experiments performed
on N-2, Ar and Ne gases are presented. The observed resonance structures e
nable us to determine the available energy resolution: a resolving power hi
gher than 8500 is obtained at the Ar 2p, N 1s and Ne K-edges when using all
the optical elements at full aperture. The total flux as a function of the
measured photon energy resolution and the characterization of the double-h
ead behaviour in delivering circularly polarized light are reported.