The 2s(2)2p(3)3s, 3p and 3d configurations in nine times ionized chlorine,Cl X

The 2S(2)2p(3)3s, 3p and 3d configurations in O-like Cl X have been analyze d using 19 new 3s-3p and 3p-3d transitions. The spectra were obtained using the beam-foil method, and the new lines, which occur between 635 and 868 A ngstrom, have an estimated wavelength uncertainty of 0.03 Angstrom. The ana lysis is supported by isoelectronic comparisons and theoretical calculation s. This work is part of an isoelectronic study of the O- and N-sequences ai med at identifying n = 3, Deltan = 0 transitions in abundant elements in th e solar coronal spectrum recorded by the SUMER instrument onboard the SOHO satellite.