关键词: spectra of Sm atom, odd-parity excited state, photoionization detection

Abstract: Two-step excitation and ionization processes are used to detect Sm atoms in many excited states populated with tunable lasers. The wavelength of the first laser is tuned to the resonances from the Sm 4f$^{6 }$6s$^{2}$ ${}^7F_{J}$ ($J$=0--6) states to many odd-parity states with different electronic configurations, where the atoms are detected by photoionization process using an ultraviolet laser with a wavelength of 355 nm. Precise measurements on the energy level and intensity for many Sm 4f$^{6}$ 6s6p and 4f$^{5}$5d6s$^{2}$ states have been carried out. In a theoretical analysis on the spectral data, such as peak position, relative intensity, many transitions can be identified as the resonances from the Sm 4f$^{6 }$6s$^2$ $^7F_{J }$ ($J$=0--6) states to the atomic states with 4f$^{6 }$6s6p and 4f$^{5}$5d6s$^{2}$ electronic configurations. This work also reports many spectral data on the odd-parity states that cannot be found in the literature.

Key words: spectra of Sm atom, odd-parity excited state, photoionization detection