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Nuclear Science and Techniques 2024年第3期35卷 40-52页

作者： Ding-Han Zhu Xiong Zhang Xiao-Qiang Li Peng Li Yan-Bin Wang Shuang Zhang State Key Laboratory of NBC Protection for Civilian Beijing 102205China

In high-altitude nuclear detonations,the proportion of pulsed X-ray energy can exceed 70%,making it a specific monitoring signal for such *** pulsed X-rays can be captured using a satellite-borne X-ray detector following atmospheric *** quantitatively analyze the effects of different satellite detection altitudes,burst heights,and transmission angles on the physical processes of X-ray transport and energy fluence,we developed an atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering *** proposed method is an improvement over the traditional analytical method that only computes direct-transmission *** traditional analytical method exhibits a maximum relative error of 67.79% compared with the Monte Carlo *** improved method reduces this error to within 10% under the same conditions,even reaching 1% in certain ***,its computation time is 48,000 times faster than that of the Monte Carlo *** results have important theoretical significance and engineering application value for designing satellite-borne nuclear detonation pulsed X-ray detectors,inverting nuclear detonation source terms,and assessing ionospheric effects.

关键词： High-altitude nuclear detonation atmospheric transmission Pulsed X-rays Scattering correction Analytical method Monte Carlo method

维普期刊数据库

Terahertz atmospheric transmission measured at the AliCPT site

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中国科学:物理学、力学、天文学英文版 2023年第9期66卷 190-195页

作者： Zhenhui Lin Wei Miao Ming Yao Feng Wu Qijun Yao Bowen Fan Boliang Liu Shengcai Shi Purple Mountain Observatory Chinese Academy of SciencesNanjing 210033China Key Lab of Radio Astronomy Chinese Academy of SciencesNanjing 210033China School of Astronomy&Space Science University of Science and Technology of ChinaHefei 230026China

Cosmic-microwave-background(CMB)B-mode measurements may reveal primordial gravitational waves from the earliest phases of the Big *** the first CMB experiment in the northern hemisphere,the Ali CMB polarization telescope(Ali CPT)will carry out measurements of this kind at Ali(Nagri)in *** is therefore of particular importance to understand the terahertz atmospheric transmission at this *** we report on the measurement results for three consecutive seasons with a Fourier transform spectrometer(FTS)spanning a wide frequency range from 0.75 to 14 *** zenith median precipitable-watervapor(PWV)is found to be as low as 1 mm at the Ali CPT site,which appears as good as those CMB B-mode measurement sites in the southern hemisphere such as Chile's Atacama Desert.

关键词： terahertz Fourier transform spectrometer(FTS) atmospheric transmission AliCPT site

维普期刊数据库

Infrared radiation simulation of exhaust system by coupling FVM with narrow band k-distribution

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航空动力学报 2012年第1期27卷 25-32页

作者： ZHU Xi-juan Eriqitai LI Xi-xi WANG Qiang School of Jet Propulsion Beijing University of Aeronautics and AstronauticsBeijing 100191China

A three-dimensional infrared radiation code for exhaust system was developed by the finite volume method coupled with narrow band k-distribution in non-gray absorbing-emitting *** final infrared signature had considered the atmosphere effect,and the simulation values were favorably consistent with testing *** results indicate that the relative errors considering the effect of atmosphere compared with that of the contrary condition reduce by 31%,it shows that when simulating the infrared radiation of the target which is received by the infrared detectors,even the calculation band is in atmospheric windows 3～5 μm,the effect of atmospheric transmission on infrared signature of the target should not be neglected.

关键词： exhaust system infrared radiation(IR) finite volume method(FVM) narrow band k-distribution atmospheric transmission

维普期刊数据库

Super-sensitive detection of quantum interferometer in atmospheric environment

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Science China(Information Sciences) 2017年第3期60卷 195-201页

作者： Yihua HU Shilong XU State key Laboratory of Pulsed Power Laser Electronic Engineering Institute Key Laboratory of Electronic Restriction of Anhui Province

With squeezed states or entangled states being the source, quantum metrology, imaging and sensing can break the standard quantum limit(SQL), even reach the Heisenberg limit(HL), which is difficult to achieve by traditional methods. However, the photon loss or phase fluctuation caused by the atmospheric attenuation and turbulence cannot be ignored in the actual application. atmospheric transmittance and phase fluctuation are related to the detection distance, and the phase sensitivity becomes worse as the distance increases. As the functions of distance, the photon loss and phase fluctuation are uniformly expressed according to the introduction of atmospheric attenuation coefficient, turbulence structure constant and receive aperture size in this *** density matrixes and phase sensitivities of N00 N states and M&M′ states in the atmospheric environment are proposed in terms of distance variables. Then the quantitative computation of super-sensitive distance is carried out. SQL-contour is proposed to describe the super-sensitive ability of the quantum interferometer for the affection from both photon loss and phase fluctuation. The simulation results show that, in atmospheric environment the super-sensitive distance can reach hundreds of meters. M&M′ states with less total photon number are more likely to reflect the advantage of super-sensitivity. SQL-contour can provide references for interferometric source choosing.

关键词： quantum interferometer standard quantum limit entangled states phase sensitivity atmospheric transmission