Beam-foil measurements of mean lives in B iv and B v below 450 Å

Abstract

Mean lives of eight terms in B iv and three in B v have been measured using the techniques of beam-foil spectroscopy. The terms in B iv and the measured mean lives are (in picoseconds): 1s2p1P0, <5; 1s4d1D, 117 ± 16; 1s3d1D, 63 ± 3; 1s3s1S, 393 ± 4; 1s4d3D, 131 ± 8; 1s3p3P0, 222 ± 4; 1s3d3D, 59 ± 3; 1s3s3S, 474 ± 28. These results and those for B v are compared with theory and previous experimental results.