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991.
A new optogalvanic technique with an rf discharge was applied to a high-resolution study of the Rydberg states of N2. The Ledbetter band, c4(0)1Πu ← a″(0)1Σg+, and a new visible band, c′5(0)1Σu+ ← a″(0)1Σg+, were studied at a Doppler-limited resolution of 0.05 cm?1. A Doppler-free method was also applied to resolve overlapped lines. Precise wavenumbers were determined for the rotational transitions of the two Rydberg bands. The rotational and the centrifugal constants for the lowest Rydberg state, a″(0)1Σg+, were determined to be B0 = 1.913748(42) cm?1 and D0 = 6.088(99) × 10?6 cm?1, where the numbers in parentheses are the standard deviation and apply to the last digits. 相似文献
992.
993.
The infrared spectrum of biphenyl was measured in an Ar matrix at 20 K. A comparison of the results with the spectra of this molecule in the solid liquid states shows that the structure of biphenyl in the matrix is similar to that in the liquid state, that is, the molecule is non-planar. 相似文献
994.
M. Suzuki 《Physica A》1976,84(1):48-67
The fluctuation of the intensity of superradiant pulse is calculated by applying a general asymptotic evaluation method of quantal macrovariables to a superradiant master equation. It is shown that the fluctuation of superradiant intensity is proportional to the cube of the number of the relevant atoms. The time-dependence of the proportional coefficient has been evaluated explicitly. It is predicted that there occurs an enhancement of fluctuation of superradiant intensity at an intermediate time. The intensity and fluctuation of higher order are also calculated. General expressions of expansion coefficients of a generating function are also given rigorously. 相似文献
995.
Blue and violet photoluminescences of Ga-doped and Al-doped 4H-SiC single crystals grown from a Si melt have been studied at 2 ~ 200 K. Luminescence spectra under continuous excitation and their dependences on temperature and excitation intensity as well as temperature dependence of the luminescence intensity are measured. Time-resolved spectra and decay curves after pulsed excitation also are observed at various temperatures. The luminescences at 2 K are found to be due to pair recombination between the N donor introduced unintentionally and the Ga or Al acceptor. The spectra of the two samples resemble each other in shape, and each consists of a zero-phonon peak and its phonon replicas. At higher temperatures, another emission appears due to the recombination of free electrons with bound holes at the acceptors in place of the pair emission. From the energies of the zero-phonon peaks of these two kinds of emissions, the ionization energies of the Ga and the Al acceptors are determined to be 249 ± 3meV+Ex and 168 ± 3 meV + Ex, respectively, where Ex is the exciton binding energy of 4H-SiC, and that of the N donor is estimated to be 55 ± 7 me V using an appropriate approximation. 相似文献
996.
K. Mizuno T. Suzuki S. Ono K. Sagae 《International Journal of Infrared and Millimeter Waves》1983,4(3):321-325
The coupling of a Gaussian radiation beam to a corner reflector with a four-wavelength long wire antenna was studied theoretically and experimentally. The antenna configuration in conjunction with a Schottky barrier diode is recently used widely as a fast submillimeter wave detector. The optimum angle focusing the radiation to the antenna has been obtained and is 11° (half-width at the 8.7dB points). 相似文献
997.
998.
999.
We have studied core polarization and exchange current effects on the magnetic form factors with the highest multipolarities allowed by the shell model:M 7 for49Ti,51V, and59Co, andM9 for87Sr and93Nb. One-pion exchange currents partially remove discrepancies between density-dependent Hartree-Fock-Bogoliubov calculations and experiments. 相似文献
1000.