Knowledge Bank

The $Y2\Sigma +-X2\Pi i$ near-infrared electronic transition of CuO was observed for the first time at high resolution, recorded with the Fourier transform spectrometer associated with the McMath Solar Telescope at Kitt Peak. The excited CuO molecules were produced in a low pressure copper hollow cathode sputter source, using 0.8 Torr neon and 15 mTorr oxygen. Preliminary constants for the $Y2\Sigma +$ states of CuO are: $T0=7715.1cm-1,B=0.470cm-1$, and $\gamma =-0.8cm-1$. The copper isotope structure is not resolved. However, each line is actually a fully resolved quartet due to quadrupole coupling of the copper nucleus $(ICu=3/2)$, due mainly to the $bfermi$ interaction in the $Y2\Sigma +$ state. The analysis of the hyperfine structure is in progress. The full analysis of this transition will be presented.