DETERMINATION OF THE VALUE OF THE RADIAL INTEGRAL FOR ELECTRIC-QUADRUPOLE TRANSITIONS BY MEASUREMENT OF THE RELATIVE INTENSITY OF MIXED MULTIPOLE LINES OF BI-I

The contribution of electric-quadrupole radiation to line intensity is determined by the radial integral of r**2 between single electron states. Formulas are given for determining the value of s//2 by measurements of the relative intensities of the mixed multipole transitions between levels of an l**n configuration, the transitions originating from the same upper level. The formulas are used to evaluate s//2 in the case of ground configuration of atomic bismuth. It is found that the value of the radial integral is s//2 equals (9. 0 plus or minus 2. 0) ea//o**2.