The Spark Spectra of Na IV and Na VI

Abstract
The spark spectra of sodium have been obtained in the region of 80 to 2400 Å using a θ-pinch and a triggered vacuum spark as sources. Analysis of the data has led us to establish nine new levels in Na IV and to classify 40 new lines in this spectrum. An additional level has been found in Na VI resulting in the classification of 4 new lines.