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低相位噪声信号的谱线宽度 被引量:1
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作者 邢小明 《现代雷达》 CSCD 北大核心 2001年第6期52-54,共3页
提出了由相位噪声计算信号谱线宽度的计算公式 ,从而计算出脉冲多普勒雷达频综器输出的激励信号的谱线宽度 。
关键词 脉冲多普勒雷达 相位噪声 线宽
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H_2(v=1)与CO_2碰撞中CO_2的振动和转动激发
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作者 张文军 封丽 +3 位作者 李佳灵 刘静 戴康 沈异凡 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2014年第6期1492-1496,共5页
利用高分辨率瞬时激光光谱技术,研究了 H2(1,1)与CO2碰撞中的能量转移。受激拉曼泵浦把 H2(0,1)激发到 H2(1,1)能级,H2(1,1)与 CO2碰撞,使 CO2的振转态得到布居,通过泛频吸收得到 CO2(00^0 0)和(00^0 1)的转动态分... 利用高分辨率瞬时激光光谱技术,研究了 H2(1,1)与CO2碰撞中的能量转移。受激拉曼泵浦把 H2(0,1)激发到 H2(1,1)能级,H2(1,1)与 CO2碰撞,使 CO2的振转态得到布居,通过泛频吸收得到 CO2(00^0 0)和(00^0 1)的转动态分布,测量 H2(0,1)和 H2(1,1)的CARS(相干反斯托克斯拉曼散射)谱,得到这二个能级布居数密度之比,而 H2(0,1)密度通过在池温300 K下 H2(v=0)的转动Boltzmann分布得到。碰撞转移速率系数由一个速率方程得到,对于CO2(00^0 0)J=48~76,速率系数ktr从(3.9±0.8)×10^-11单调递增到(1.4±0.3)×10^-10 cm^3·molecule^-1·s^-1,而对于(00^0 1)J=5~33,速率系数均在(4.3±0.9)×10^-12 cm^3·molecule^-1·s^-1附近。随 H2(1,1)的激发,在0.5μs 内测量CO2(00^0 0)和(00^0 1)原生态的转动布居,得到玻尔兹曼转动温度Trot,对于(00^0 0)态,有Trot=1100 K,对于(00^0 1)态有Trot=310 K,与池温接近。利用泛频吸收线的多普勒增宽测量,得到CO2各转动态的实验室平移温度Ttran和质心平移温度Trel ,对于(00^0 0)J=48和76,Trel分别为454和1532 K,平动能平均变化在231~1848 cm^-1之间,而对于(00^0 1)J=5~33,平均平动能基本无变化。 展开更多
关键词 激光光谱 能量转移 速率系数 多普勒线宽 H2-CO2
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The correlation between the Doppler factor and broad line region luminosity in blazars 被引量:1
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作者 DU LeiMing BAI JinMing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第10期1938-1944,共7页
The disk-jet symbiosis is a fundamental problem in our understanding of the Active Galactic Nuclei (AGN). We explore the relation between the Doppler factors d of the jet of blazars and their broad line region lumin... The disk-jet symbiosis is a fundamental problem in our understanding of the Active Galactic Nuclei (AGN). We explore the relation between the Doppler factors d of the jet of blazars and their broad line region luminosity LBLR. Since different methods measuring δ might differ substantially, we use data obtained from 3 independent methods and compile 3 samples of sources for each of them, respectively. Two samples consist of blazars, that is, Flat Spectrum Radio Quasars (FSRQs) and BL Lacertae objects (BL Lacs), and the other consists of BL Lacs. dis one of the most important jet properties and LBLR is thought to be the proxy of the accretion power. Correlation analysis to these samples shows that there exists a significant correlation between δ and LBLR, which supports the idea that the jet powering process is closely linked with the accretion process and provides new evidence for disk-jet connection. Furthermore, the results are consistent with the idea that the Blandford-Znajek mechanism is sufficient for BL Lacs and a hybrid model is needed for FSRQs. 展开更多
关键词 Doppler factor broad line region luminosity jet power accretion power
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