Knowledge Bank

A molecular beam electric resonance spectrometer has been used to observe pure hyperfine transistions of all four isotopic forms of rubidium chloride, with a linewidth of about 150 Hz. So far 179 observed lines have been identified as belonging to $\mathrm{<mrow\; data-mjx-texclass="ORD">85</mrow>}Rb35Cl$, and tentatively fitted to determine the hyperfine constants, including nuclear quadrupole and spin-rotation interactions for both nuclei, and the tensor and scalar spin-spin interactions, for vibrational states $v=0-3$ and rotational states $J=1-6$. An additional 103 lines have been identified and fitted for $\mathrm{<mrow\; data-mjx-texclass="ORD">87</mrow>}Rb35Cl$. The possibilities of a rubidium nuclear octupole interaction, and (in the case of $\mathrm{<mrow\; data-mjx-texclass="ORD">85</mrow>}Rb)$ a nuclear electric hexadecapole interaction, are also being considered.