Measurements of Beam-Foil Spectra of Highly Ionized Chlorine Ions in the Region of 170-260 Å

A Beam-foil study was made on highly ionized chlorine ions. Emission lines in the wavelength region from 170 A to 260 A were observed and most of the lines were due to the 2 s -2 p transitions belonging to Cl XII-Cl XIV. Two lines at ∼180 A and ∼206 A are newly identified as transitions between high n l levels of Cl XV and Cl XIV. The lifetimes of 2 s 2 p 1 P 1 and 2 p 2 1 D 2 levels in Cl XIV were determined from the intensity decay curve of 237.7 Aobtained with time-of-flight technique to be 0.14 nsec and 0.60 nsec, respectively.