Knowledge Bank

A new $\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}\Pi 1-X3\Sigma -$ electronic of NiO has been observed in the near infrared extending from 2.1 to 2.4 $\mu$m. The molecules were excited in emission from the Ni hollow cathode and the spectra were observed using the Fourier transform spectrometer associated with the McMath Solar Telescope of the National Solar Observatory at Kitt Peak. The observed spectrum consists of the 0-0 band for the $\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}\Pi 0-3\Sigma 1-3\Pi 1-3\Sigma 0$ subbands and the 1-1 band of the $\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}\Pi 1-3\Sigma 0$ subband. The subbands involving the $\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}\Pi 2$ spin component were not observed. The molecular constants including the A- doubling constants in the new $\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}\Pi 1$ state have been extracted from the observed data. A new system of CoO has also been observed in the 1.7 to 1.9 $\mu$m region. The analysis of this transition is in progress.