COLLISION SPECTROSCOPY OF QUARTET AND DOUBLET TRANSITIONS IN DOUBLY-EXCITED NE7+

We present the observation of VUV transitions between doubly excited s tates of Ne7+. Spectra were selectively produced by single electron ca pture in a cesium vapor by Ne8+ ions prepared in the metastable state 1s2s S-3 by a previous collision of a Ne9+ beam with a gas target. The observed lines were assigned to 1s2l2l' --> 1s2lnl '' and 1s2l3d --> 1s2lnf electric dipole transitions. Furthermore, the forbidden electri c quadrupole transition 1s2s2p P-4(o)-1s2p3d F-4(o) has been identifie d at 78.71 Angstrom.