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971.
Carbon monosulfide was detected in outer space by rovibrational spectroscopy of the X 1Σ+ state and A 1Π – X 1Σ+ system. This work calculated the potential energy curves and dipole moment functions of the X 1Σ+ 0+ and A 1Π1 states, and computed the transition dipole moments between the two states employing the CASSCF method, followed by the valence icMRCI approach. Core-valence correlation and scalar relativistic corrections were included. The extrapolation of potential energies to the complete basis set limit was performed. The spin-orbit coupling effect was included. The Einstein A coefficients, band origins, and oscillator strengths were calculated for the rovibrational transitions when J?≤?150. The rovibrational transitions of the X 1Σ+ 0+ and A 1Π1 states became very weak when Δυ?≥?6. The Einstein A coefficients of vibronic emissions of the A 1Π1 – X 1Σ+ 0+ system were large, indicating that the emissions were able to be measured easily through spectroscopy. Several rovibrational transitions of the A 1Π1 – X 1Σ+ 0+ system were analysed in detail. The distribution of radiative lifetime varying as rotational quantum number was calculated. The results obtained in this work agree well with the available experimental values. 相似文献
972.
In this paper,we discuss the P-v criticality and the heat engine efficiency in the Bardeen EinsteinGauss-Bonnet (EGB) AdS black hole space-time.From the P-v plane in the extended phase space,we find that the Bardeen EGB-AdS black hole conforms to Van der Waals (VdW) liquid-gas systems in the extended phase space,and P_cv_/T_c=0.369 of the Bardeen EGB-AdS black hole system is between 0.3333 of the Gauss-Bonnet AdS black hole system and 0.375 of the VdW gas system in the 5-dimensions.Then we construct a heat engine by taking the Bardeen EGB-AdS black hole as the working substance,and consider a rectangle heat cycle in the P-v plane.We find that two cases with different Bardeen parameter e and Gauss-Bonnet parameter a both have the same situation,i.e.as the entropy difference between small black hole and large black hole S2 increases,the heat engine efficiency will increase.Furthermore,as the Bardeen parameter e increases,the efficiency will decrease.However,for the Gauss-Bonnet parameter a,the result is contrary.By comparing with the well-know Carnot heat engine efficiency,we have found the efficiency ratioη/η_c versus entropy S_2 is bounded below l,so it is coincided with the thermodynamical second law. 相似文献
973.
We study the quantum dynamics of an impurity-doped Bose–Einstein condensate (BEC) system. We show how to generate the macroscopic quantum superposition states (MQSSs) of the BEC by the use of projective measurements on impurity atoms. It is found that the nonclassicality of MQSSs can be manipulated by changing the number of the impurities and their interaction with the BEC. It is shown that the BEC matter-wave field exhibits a collapse and revival phenomenon which reveals the quantum nature of the BEC matter-wave field. We investigate the micro-macro entanglement between the impurities and the BEC, and find enhancement of the micro-macro entanglement induced by the initial quantum coherence of the impurity atoms. 相似文献
974.
A complete classification of static
space times with maximal symmetric
transverse spaces is provided, according to their Ricci collineations.
The classification is made when one component of Ricci collineation vector
field V is non-zero (cases 1~4), two components of
V are non-zero (cases 5~10), and three components of V are non-zero (cases 11~14), respectivily.
Both non-degenerate (det Rab ≠0) as well as the
degenerate (det Rab=0) cases are discussed and some new
metrics are found. 相似文献
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Ulf Leonhardt 《Annalen der Physik》2018,530(5)
A recent article [J. Steinhauer, Nat. Phys. 2016 , 12, 959] has reported the observation of quantum Hawking radiation and its entanglement in an analogue black hole. Here, the published evidence, its consistency with theoretical bounds, and the statistical significance of the results are analyzed. The analysis raises severe doubts on the observation of Hawking radiation. 相似文献