LINE OVERLAP MEASUREMENT FOR THE PHOTOPUMPING OF X-RAY LASING TRANSITIONS BETWEEN N=3 AND N=2 AUTOIONIZING STATES OF LITHIUM-LIKE AL

We performed a detailed measurement of the K beta spectrum of He-like Al11+, including the dielectronic satellite spectrum excited by the KL M resonances, and comparisons with theoretical predictions from multi- configuration Dirac-Fock calculations are made. We investigated the po ssibility of a line overlap between the (1s(2)2s) (J=1/2-)(1s2s3p)(J=3 /2) transition in Li-like Al10+ and the (2s(2)2p(6))(J=0)-(2s(2)2p(1/2 )(5)3s)(J=1) transition in Ne-Like Rb27+, situated near 1826 eV, to ex amine their suitability for use in a photopumped X-ray laser scheme. I n this scheme with lasing at 46 Angstrom, the Rb27+ line pumps the Al1 0+ upper lasing level. The measured difference in the line energies is 0.7 +/- 0.1 eV or 380 ppm.