Ground state hyperfine structures of 43K and 44K measured by atomic beam magnetic resonance coupled with laser optical pumping

Abstract
The ground state hyperfine structures of 43 K and 44K have been measured by an atomic beam magnetic resonance method in which the atoms are spin-polarized by laser optical pumping. The spectroscopic results are : Δv43( 2S1/2) = 192.648 4 (30) MHz and Δν44( 2S1/2) = - 946.718 (3) MHz. The sensitivity of our method is compared to the one achieved in classical ABMR apparatus