Absorption and Faraday spectroscopy of the 876 nm line in Bi I

The transition 6p 3 4 S 3/2 -6p 3 2 D 3/2 at 876 nm in atomic bismuth has been studied by laser spectroscopy. The absorption spectrum and the Faraday rotation spectrum have been measured over the frequency range occupied by the hyperfine structure, giving the following values for the interaction constants: A( 2 D 3/2 )=-1226.7(1.2) MHz, B( 2 D 3/2 )=-617(10) MHz. From the Faraday rotation spectrum the ratio of the reduced electric quadrupole and magnetic dipole matrix elements, ( 4 S 3/2 //( omega /4 square root 3)*(-2er 2 C (2) )// 2 D 3/2 )/( 4 S 3/2 // mu // 2 D 3/2 ), was found to be 0.117(8). When the interaction constants are combined with data for the other levels of the 6p 3 configuration, there is disagreement with the parameterisation of the fine and hyperfine structure given by Dembczynski et al. (1975, 1983).