Using the optical-optical double resonance (OODR) technique, we have studied the collisional broadening of some 21△g←B1πu lines in Na2 molecules. A single line Ar+ laser is used to pump the sodium dimers from t...Using the optical-optical double resonance (OODR) technique, we have studied the collisional broadening of some 21△g←B1πu lines in Na2 molecules. A single line Ar+ laser is used to pump the sodium dimers from thermally populated ground state X^1∑^+g level to the intermediate B1πu state. Then, a single-mode diode laser is used to probe the doubly excited 21△g state. The broadening rate coefficient is determined from the slope of the total linewidth versus Ne density curve. We obtain the average value kbr = (1.1 ± 0.5)×10^-8 cm^3 8^-1. The collisional excitation transfer between rotational levels of the B1πu state (i.e.,B1πu(2,83/84) ←B1Ⅱu (2,82)) is also investigated. The rates can be determined from the relative intensities of the main peak and satellite lines, combined with a rate equation model. The rates of 1.25 × 106 and 1.07 × 106 s^-1 are obtained, respectively.展开更多
基金This work was supported by the National Natural Science Foundation of China under Grant No. 10264004.
文摘Using the optical-optical double resonance (OODR) technique, we have studied the collisional broadening of some 21△g←B1πu lines in Na2 molecules. A single line Ar+ laser is used to pump the sodium dimers from thermally populated ground state X^1∑^+g level to the intermediate B1πu state. Then, a single-mode diode laser is used to probe the doubly excited 21△g state. The broadening rate coefficient is determined from the slope of the total linewidth versus Ne density curve. We obtain the average value kbr = (1.1 ± 0.5)×10^-8 cm^3 8^-1. The collisional excitation transfer between rotational levels of the B1πu state (i.e.,B1πu(2,83/84) ←B1Ⅱu (2,82)) is also investigated. The rates can be determined from the relative intensities of the main peak and satellite lines, combined with a rate equation model. The rates of 1.25 × 106 and 1.07 × 106 s^-1 are obtained, respectively.