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基于COSMIC掩星观测的顶部电离层标高特征分析
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作者 韩超 庞岗 +7 位作者 靳睿敏 甄卫民 王丹丹 马雪纯 朱庆林 陈龙江 陈丽 白培瑞 《电波科学学报》 CSCD 北大核心 2024年第2期253-261,共9页
顶部电离层是指F2层电子密度最大值所在高度以上的电离层区域。掩星观测能够提供地面到低轨卫星轨道高度处的整个电离层电子密度剖面,对于顶部电离层的研究具有重要作用。标高是构建顶部以上电离层电子密度剖面模型的重要参数。本文使用... 顶部电离层是指F2层电子密度最大值所在高度以上的电离层区域。掩星观测能够提供地面到低轨卫星轨道高度处的整个电离层电子密度剖面,对于顶部电离层的研究具有重要作用。标高是构建顶部以上电离层电子密度剖面模型的重要参数。本文使用2007—2020年的气象、电离层和气候星座观测系统(Constellation Observing System for Meteorology,Ionosphere and Climate,COSMIC)掩星观测数据,提取有效电子密度剖面数据的顶部标高,分析了其随地方时、季节、经纬度和太阳活动水平的变化特性。结果表明:顶部标高具有明显的日变化和季节变化规律,并且表现出强烈的太阳活动依赖性;顶部标高在纬度上的变化强烈依赖于地方时,同时在东西经向上表现出明显的波状结构,且这种经度波状结构在南北半球具有不同的形态;顶部标高在夏季半球具有显著的东西经向差异,南半球夏季更为明显。 展开更多
关键词 cosmic掩星 顶部电离层 电子密度剖面 太阳活动 标高
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COSMIC电离层掩星反演模拟及星座优化
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作者 许波波 王成 +3 位作者 张雨露 文援兰 何丽娜 李桢 《空间科学学报》 CAS CSCD 北大核心 2024年第1期71-79,共9页
基于卫星导航系统精密星历和NeQuick模型模拟COSMIC星座电离层掩星事件的几何过程和物理数据,并采用改正TEC法和“洋葱分层”算法反演电离层三维电子密度.模拟反演得到的电子密度廓线与模型变化趋势一致,偏差较小.电离层h_(m)F_(2),N_(m... 基于卫星导航系统精密星历和NeQuick模型模拟COSMIC星座电离层掩星事件的几何过程和物理数据,并采用改正TEC法和“洋葱分层”算法反演电离层三维电子密度.模拟反演得到的电子密度廓线与模型变化趋势一致,偏差较小.电离层h_(m)F_(2),N_(m)F_(2)的绝对误差分别为4.2 km和0.26×10^(4)cm^(–3),相对误差分别为1.66%和4.95%,反演值与模型值的线性回归决定系数R2分别为0.956和0.950,表明掩星反演模拟完整可靠、正确有效.在几何模拟正确的基础上,分析了COSMIC-2完全组网时的掩星观测性能及多系统GNSS对掩星数量及空间分布特征的影响.为提高未来掩星事件的时效性及时空分布的均匀性,提出了一种掩星分布均匀性指数,并且通过非支配排序遗传算法实现掩星星座卫星总数、轨道面数、轨道倾角的最优确定. 展开更多
关键词 cosmic 电离层 掩星反演 模拟 电子密度
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COSMIC-2近实时廓线反演对流层延迟及其质量分析
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作者 胡方鑫 叶世榕 +3 位作者 罗佳 夏朋飞 曾旭平 马鑫程 《导航定位学报》 CSCD 北大核心 2024年第5期27-35,共9页
为了进一步提高全球大气探测和极端天气预报的精度,提出一种气象、电离层与气候星座观测系统2代(COSMIC-2)近实时廓线反演对流层延迟方法:指出随着气象、电离层与气候星座观测系统2代(COSMIC-2)掩星探测深度的加深,通过掩星手段为地表... 为了进一步提高全球大气探测和极端天气预报的精度,提出一种气象、电离层与气候星座观测系统2代(COSMIC-2)近实时廓线反演对流层延迟方法:指出随着气象、电离层与气候星座观测系统2代(COSMIC-2)掩星探测深度的加深,通过掩星手段为地表全球卫星导航系统(GNSS)观测站提供近实时先验天顶对流层延迟(ZTD)产品成为可能;采用COSMIC-2掩星Level 2近实时产品wetPf2大气湿度廓线获取掩星ZTD,并以欧洲中期数值天气预报中心第五代再分析资料(ERA5)作为参考,分高程、纬度、季节评估其反演精度。结果表明,COSMIC-2掩星反演天顶对流层延迟ZTD整体精度较高,10 km高程以下全球定位系统(GPS)信号反演ZTD精度较格洛纳斯卫星导航系统(GLONASS)信号更优;掩星反演ZTD精度随高程增加而提升,在0~1 km高程范围内精度最低,均方根(RMS)分别为11.33 mm(GPS)、11.54 mm(GLONASS);中低纬度区域(25°N—35°N)反演ZTD精度低于低纬(15°N—25°N)和中纬(35°N—45°N)区域,其中中纬区域精度最高,RMS分别为4.74 mm(GPS)、4.70 mm(GLONASS);掩星反演ZTD精度同样受季节影响,GPS/格洛纳斯全球卫星导航系统(GLONASS)双模信号均在夏季反演精度最差,冬季反演精度最高,冬季RMS分别为4.15 mm(GPS)、4.18 mm(GLONASS)。 展开更多
关键词 气象、电离层与气候星座观测系统2代(cosmic-2) 全球卫星导航系统(GNSS)近实时掩星 天顶对流层延迟 质量分析
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Cosmic Ray-driven Bioenergetics for Life in Molecular Clouds
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作者 FENG Lei 《天文学报》 CAS CSCD 北大核心 2024年第6期26-31,共6页
According to models such as panspermia or the Nebula-Relay hypothesis,the ancestors of life on Earth once lived in molecular clouds.Then what are the energy source and bioenergetics for such lifeforms?A new bioenerget... According to models such as panspermia or the Nebula-Relay hypothesis,the ancestors of life on Earth once lived in molecular clouds.Then what are the energy source and bioenergetics for such lifeforms?A new bioenergetic mechanism powered by cosmic ray ionization of hydrogen molecules is proposed and its relation with the origin of chemiosmosis is also discussed in this paper.Based on this mechanism,the Last Universal Common Ancestor may be a type of lifeform that utilizes hydrogen molecules as donors of electron transport chains. 展开更多
关键词 ASTROBIOLOGY ASTROCHEMISTRY interstellar medium(ISM) NEBULAE cosmic ray
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“推拉式”嵌入式软件项目群规模评价研究——基于COSMIC模型
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作者 张恒 阮华英 《武汉工程职业技术学院学报》 2024年第3期32-35,51,共5页
针对常规COSMIC模型无法适应推拉式嵌入式软件规模评价的不足,提出一种经本地化扩展的改进COSMIC规模评价方法。通过WBS来增强对用户功能需求、嵌入式软件工程结构及组件间依赖性的理解,基于项目群基线功能集合与待估项目功能组件差异,... 针对常规COSMIC模型无法适应推拉式嵌入式软件规模评价的不足,提出一种经本地化扩展的改进COSMIC规模评价方法。通过WBS来增强对用户功能需求、嵌入式软件工程结构及组件间依赖性的理解,基于项目群基线功能集合与待估项目功能组件差异,度量出待估项目的功能点,接着引入组件逻辑复杂度调整因子,对COSMIC实施本地化扩展。最后,基于某AIoT蓝牙语音遥控器项目实施验证,结果表明,该方法保证度量效率前提下,提高规模评价的准确度和实用性,为项目进度管理和成本估算提供可靠依据。 展开更多
关键词 cosmic 软件规模评价 本地化扩展 推拉式 嵌入式软件
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Dynamical Dark Energy in Light of Cosmic Distance Measurements.Ⅰ.A Demonstration Using Simulated Datasets
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作者 Gan Gu Xiaoma Wang +2 位作者 Xiaoyong Mu Shuo Yuan Gong-Bo Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期7-14,共8页
We develop methods to extract key dark energy information from cosmic distance measurements including the BAO scales and supernova(SN) luminosity distances.Demonstrated using simulated data sets of the complete DESI,L... We develop methods to extract key dark energy information from cosmic distance measurements including the BAO scales and supernova(SN) luminosity distances.Demonstrated using simulated data sets of the complete DESI,LSST and Roman surveys designed for BAO and SN distance measurements,we show that using our method,the dynamical behavior of the energy,pressure,equation of state(with its time derivative) of dark energy and the cosmic deceleration function can all be accurately recovered from high-quality data,which allows for robust diagnostic tests for dark energy models. 展开更多
关键词 (cosmology:)dark energy (cosmology:)large scale structure of universe (cosmology:)cosmic background radiation (cosmology:)cosmological parameters
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The Tension Cosmology, Largest Cosmic Structures and Explosions of Supernovae from SST
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作者 Sylwester Kornowski 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1029-1044,共16页
Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter lea... Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter leads to the disagreement in the galaxy clustering amplitude, quantified by the parameter S8. Within the same model we described the Hubble tension. We described also the mechanism that transforms the gravitational collapse into an explosion—it concerns the dynamics of virtual fields that lead to dark energy. Our calculations concern the Type Ia supernovae and the core-collapse supernovae. We calculated the quantized masses of the progenitors of supernovae, emitted total energy during explosion, and we calculated how much of the released energy was transferred to neutrinos. Value of the speed of sound in the strongly interacting matter measured at the LHC confirms that presented here model is correct. Our calculations show that the Universe is cyclic. 展开更多
关键词 Scale-Symmetric Theory Tension Cosmology Coupling Constants Parameters σ8 and S8 Largest cosmic Structures Dark Energy Supernova Explosion Cyclic Universe
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Transport in Astrophysics: VI. Ultra-High Energy Cosmic Rays
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2024年第1期65-84,共20页
Two new solutions of the homogeneous diffusion equation in 1D are derived in the presence of losses and a trigonometric profile for a profile of density. A simulation for the ankle in the energy distribution of cosmic... Two new solutions of the homogeneous diffusion equation in 1D are derived in the presence of losses and a trigonometric profile for a profile of density. A simulation for the ankle in the energy distribution of cosmic rays (CRs) is provided in the framework of the fine tuning of the involved parameters. A theoretical image for the overall diffusion of CRs in galactic coordinates is provided. 展开更多
关键词 cosmic Rays Particle Diffusion Random Walks
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The 111-Years-Old Cosmic Ray Puzzle Has Been Solved?
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作者 Shlomo Dado Arnon Dar 《Journal of Modern Physics》 2024年第1期125-131,共7页
We show that recently multi-messenger astronomy has provided compelling evidence that the bulk of high energy cosmic rays (CRs) are produced by highly relativistic narrow jets of plasmoids launched in core collapse of... We show that recently multi-messenger astronomy has provided compelling evidence that the bulk of high energy cosmic rays (CRs) are produced by highly relativistic narrow jets of plasmoids launched in core collapse of stripped-envelope massive stars to neutron stars and stellar mass black holes. Such events produce also a visible GRB if the jet happens to point in our direction. This has been long advocated by the cannon ball (CB) model of high energy CRs and GRBs, but the evidence has been provided only recently by what were widely believed to be unrelated discoveries. They include the very recent discovery of a knee around TeV in the energy spectrum of high energy CR electrons, the peak photon energy in the “brightest of all time” GRB221009A, and the failure of IceCube to detect high energy neutrinos from GRBs, including GRB221009A. They were all predicted by the cannonball (CB) model of high energy CRs and GRBs long before they were discovered in observations, despite a negligible probability to occur by chance. 展开更多
关键词 cosmic Rays Gamma Ray Bursts Neutrino Bursts
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Algorithms for Empirical Equations in Terms of the Cosmic Microwave Background Temperature
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作者 Tomofumi Miyashita 《Journal of Modern Physics》 2024年第10期1567-1585,共19页
Previously, we presented several empirical equations using the cosmic microwave background (CMB) temperature. Next, we propose an empirical equation for the fine-structure constant. Considering the compatibility among... Previously, we presented several empirical equations using the cosmic microwave background (CMB) temperature. Next, we propose an empirical equation for the fine-structure constant. Considering the compatibility among these empirical equations, the CMB temperature (Tc) and gravitational constant (G) were calculated to be 2.726312 K and 6.673778 × 10−11 m3∙kg−1∙s−2, respectively. Every equation can be explained numerically in terms of the Compton length of an electron (λe), the Compton length of a proton (λp) and α. Furthermore, every equation can also be explained in terms of the Avogadro number and the number of electrons at 1 C. We show that every equation can be described in terms of the Planck constant. Then, the ratio of the gravitational force to the electric force can be uniquely determined with the assumption of minimum mass. In this report, we describe the algorithms used to explain these equations in detail. Thus, there are no dimension mismatch problems. 展开更多
关键词 Temperature of the cosmic Microwave Background Minimum Mass The Ratio of Gravitational Force to Electric Force Dimension Analysis Redefinition Method Fine Structure Constant
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Ratio of Gravitational Force to Electric Force from Empirical Equations in Terms of the Cosmic Microwave Background Temperature
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作者 Tomofumi Miyashita 《Journal of Modern Physics》 2024年第5期674-689,共16页
Previously, we presented several empirical equations using the cosmic microwave background (CMB) temperature. Next, we propose an empirical equation for the fine-structure constant. Considering the compatibility among... Previously, we presented several empirical equations using the cosmic microwave background (CMB) temperature. Next, we propose an empirical equation for the fine-structure constant. Considering the compatibility among these empirical equations, the CMB temperature (T<sub>c</sub>) and gravitational constant (G) were calculated to be 2.726312 K and 6.673778 × 10<sup>−11</sup> m<sup>3</sup>∙kg<sup>−1</sup>∙s<sup>−2</sup>, respectively. Every equation could be explained in terms of the Compton length of an electron (λ<sub>e</sub>), the Compton length of a proton (λ<sub>p</sub>) and a. Furthermore, every equation could also be explained in terms of Avogadro’s number and the number of electrons in 1 C. However, the ratio of the gravitational force to the electric force cannot be uniquely determined when the unit of the Planck constant (Js) is changed. In this study, we showed that every equation can be described in terms of Planck constant. From the assumption of minimum mass, the ratio of gravitational force to electric force could be elucidated. 展开更多
关键词 Ratio of Gravitational Force to Electric Force Minimum Mass Temperature of the cosmic Microwave Background
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Correspondence Principle for Empirical Equations in Terms of the Cosmic Microwave Background Temperature with Solid-State Ionics
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作者 Tomofumi Miyashita 《Journal of Modern Physics》 2024年第1期51-63,共13页
Previously, we presented several empirical equations using the cosmic microwave background (CMB) temperature that were mathematically connected. Next, we proposed an empirical equation for the fine-structure constant.... Previously, we presented several empirical equations using the cosmic microwave background (CMB) temperature that were mathematically connected. Next, we proposed an empirical equation for the fine-structure constant. Considering the compatibility among these empirical equations, the CMB temperature (T<sub>c</sub>) and gravitational constant (G) were calculated to be 2.726312 K and 6.673778 × 10<sup>-11</sup> m<sup>3</sup>·kg<sup>-1</sup>·s<sup>-2</sup>, respectively. Every equation can be explained in terms of the Compton length of an electron (λ<sub>e</sub>), the Compton length of a proton (λ<sub>p</sub>) and α. However, these equations are difficult to follow. Using the correspondence principle with the thermodynamic principles in solid-state ionics, we propose a canonical ensemble to explain these equations in this report. For this purpose, we show that every equation can be explained in terms of Avogadro’s number and the number of electrons in 1 C. 展开更多
关键词 Temperature of the cosmic Microwave Background
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Cosmic Contributions to the Deposition of Petroleum Source Rocks: Review and Analysis 被引量:1
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作者 Heinz-Jürgen Brink 《International Journal of Geosciences》 2023年第11期1123-1145,共23页
The development of globally distributed Phanerozoic petroleum source rocks is concentrated on time intervals, which correlate convincingly with climatic driven glaciation epochs of Earth’s history, repeated every 150... The development of globally distributed Phanerozoic petroleum source rocks is concentrated on time intervals, which correlate convincingly with climatic driven glaciation epochs of Earth’s history, repeated every 150 million years, and during sea level high stands and maxima of global magmatism with a period of 300 million years. The 150 million year periodicity appears to be related to the path of the solar system through the spiral arms of the Milky Way and the 300 million year periodicity to changes of the spiral system. The spiral arms are preferred birth places of new stars, of which the larger ones have only smaller lifespans. Their preliminary deaths ended with explosions and selectively with the development of so-called white dwarfs, neutron stars or black holes. The times of the explosions of intermediate (sun-like) stars can be determined by measuring the present brightness of the dwarfs. Not surprisingly the last two maxima of recordable near solar system star explosions took place during the presumably spiral arms driven glacial epochs in Eocene to present and Upper Jurassic times. Such near solar system star explosions may have been the source of intense neutrino showers, cosmic rays and star dust. This dust contained all kinds of chemical elements, including phosphorus and uranium. Such cosmic phosphorus may have supported, through fertilizing, the distribution of life on Earth additionally to local phosphorus resources via bloom of biota in lakes and oceans and the enhanced growth of plants on land across all climatic zones. Subsequently it maintained the development of petroleum source rocks of all organic matter types within black shales and coals. Via the distribution of remnants of exploding stars—mainly white dwarfs, but neutron stars and black holes have to be counted as well—a cosmic contribution can therefore casually linked to the deposition of petroleum source rocks on Earth, not only purely correlatively by their contemporaneous appearances. 展开更多
关键词 cosmic Rays cosmic Dust Milky Way Spiral Arms Stars PHOSPHORUS URANIUM Petroleum Source Rock
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COSMIC与ERA-Interim折射率数据分析海洋边界层时空分布的对比
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作者 袁帅 唐歌实 高鹏 《南京信息工程大学学报(自然科学版)》 CAS 北大核心 2023年第2期244-252,共9页
本文基于小波协方差变换法,使用COSMIC和ERA-Interim两种数据的折射率获取了全球海洋边界层的时空分布情况并进行了对比分析.结果表明:在空间上,由两种数据反演出的海洋边界层高度所显示出的分布特征大致相同,即沿着赤道呈不完全对称分... 本文基于小波协方差变换法,使用COSMIC和ERA-Interim两种数据的折射率获取了全球海洋边界层的时空分布情况并进行了对比分析.结果表明:在空间上,由两种数据反演出的海洋边界层高度所显示出的分布特征大致相同,即沿着赤道呈不完全对称分布,仅在个别海域有所差别;在季节及月变化方面,两者均呈现出夏季较高的特点;在日变化特征上,两者变化均不明显,但ERA-Interim数据的海洋边界层高度的日变化特征与太阳辐射的日变化特征更加符合;在数值差异上,COSMIC数据要比ERA-Interim数据的结果高500~1000 m,且低纬度地区两者差异大于高纬度地区,夏季两者差异小于冬季. 展开更多
关键词 cosmic掩星 ERA-INTERIM 折射率 海洋边界层 小波协方差变换法 时空分布特征
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基于不同背景场的云内COSMIC掩星资料的偏差分析
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作者 殷延安 杨胜朋 《高原气象》 CSCD 北大核心 2023年第5期1351-1360,共10页
利用2007-2009年Cloud Sat卫星云廓线雷达(nadir-pointing cloud profiling radar,CPR)资料,气象、电离层和气候卫星联合观测系统(Global Constellation Observing System for Meteorology,Ionosphere,and Climate,COSMIC)掩星资料,分... 利用2007-2009年Cloud Sat卫星云廓线雷达(nadir-pointing cloud profiling radar,CPR)资料,气象、电离层和气候卫星联合观测系统(Global Constellation Observing System for Meteorology,Ionosphere,and Climate,COSMIC)掩星资料,分析了不同类型云内COSMIC掩星资料与欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts,ECMWF)和美国国家环境预报中心(National Centers for Environmental Prediction,NCEP)分析场之间的折射率偏差特征。COSMIC与ECMWF和NCEP之间的折射率偏差分别用Nbias^(ECMWF)和Nbias^(NCEP)表示。研究发现,Nbias^(ECMWF)在积云、层积云、高积云和高层云中的最大值分别为1.2%、0.2%、0.5%和0.2%,而Nbias^(NCEP)则分别为1.8%、0.5%、0.5%和0.4%。在层积云的对流层下层Nbias^(NCEP)存在较大的负值,而Nbias^(ECMWF)为正值。折射率的正偏差随着液态水含量增加而增加。从全球分布来看,赤道辐合带云量丰富,Nbias^(NCEP)和Nbias^(ECMWF)也存在明显的正偏差,它在空间上和水汽的正偏差以及温度的负偏差高度相关。 展开更多
关键词 cosmic掩星 CLOUDSAT 折射率偏差 液态水含量
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Potential for Constraining Propagation Parameters of Galactic Cosmic Rays with the High Energy Cosmic-radiation Detection Facility on Board China's Space Station 被引量:1
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作者 Zhi-Hui Xu Qiang Yuan +1 位作者 Zhi-Cheng Tang Xiao-Jun Bi 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第8期290-296,共7页
Precise measurements of the spectra of secondary and primary cosmic rays are crucial for understanding the origin and propagation of those energetic particles.The High Energy Cosmic-radiation Detection(HERD)facility o... Precise measurements of the spectra of secondary and primary cosmic rays are crucial for understanding the origin and propagation of those energetic particles.The High Energy Cosmic-radiation Detection(HERD)facility on board China's Space Station,which is expected to operate in 2027,will push the direct and precise measurements of cosmic-ray fluxes up to PeV energies.In this work,we investigate the potential of HERD for studying the propagation of cosmic rays using measurements of boron,carbon,and oxygen spectra.We find that,compared with the current results,the new HERD measurements can improve the accuracy of the propagation parameters by 8%–40%.The constraints on the injection spectra at high energies will also be improved. 展开更多
关键词 (ISM:)cosmic rays-instrumentation detectors-The Galaxy
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利用改进的GoogLeNet深度学习模型识别COSMIC-2掩星信号中的反射信号 被引量:1
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作者 罗文杰 项杰 杜华栋 《大气科学》 CSCD 北大核心 2023年第3期631-641,共11页
GPS(Global Positioning System)掩星探测技术作为一种先进的大气探测手段,已广泛用于数值天气预报、气候和空间天气研究。掩星探测存在的问题之一是容易受到地球表面反射信号的干扰,识别和分离掩星探测信号中的反射信号有助于将掩星数... GPS(Global Positioning System)掩星探测技术作为一种先进的大气探测手段,已广泛用于数值天气预报、气候和空间天气研究。掩星探测存在的问题之一是容易受到地球表面反射信号的干扰,识别和分离掩星探测信号中的反射信号有助于将掩星数据同化到数值天气预报系统中去,具有重要意义。本文提出一种基于改进的GoogLeNet深度学习模型(Im-GNet),并应用于COSMIC-2掩星探测数据来识别反射信号。本文选择了2020年1月1~9日的COSMIC-2掩星数据(conPhs文件),进行质量控制后,利用无线电全息方法得到掩星信号的无线电全息功率谱密度图像,然后训练得到Im-GNet深度学习模型,Im-GNet模型测试的准确率达到了96.4%,显著高于支持向量机(SVM)方法的结果。本文还分析了反射信号对掩星数据的影响,掩星事件的地理分布以及掩星反演数据(atmPrf文件)与NCEP再分析资料的12 h预报值(avnPrf文件)的折射率比较表明:有反射信号的掩星事件数据质量更好,所包含的大气信息更丰富。 展开更多
关键词 cosmic-2掩星 深度学习 无线电全息技术 GoogLeNet模型
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Injection Spectra of Different Species of Cosmic Rays from AMS-02, ACE-CRIS and Voyager-1
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作者 Xu Pan Qiang Yuan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第11期7-13,共7页
Precise measurements of energy spectra of different cosmic ray(CR) species have been obtained in recent years, by particularly the AMS-02 experiment on the International Space Station. It has been shown that apparent ... Precise measurements of energy spectra of different cosmic ray(CR) species have been obtained in recent years, by particularly the AMS-02 experiment on the International Space Station. It has been shown that apparent differences exist in different groups of the primary CRs. However, it is not straightforward to conclude that the source spectra of different particle groups are different since they will experience different propagation processes(e.g., energy losses and fragmentations) either. In this work, we study the injection spectra of different nuclear species using the measurements from Voyager-1 outside the solar system, and ACR-CRIS and AMS-02 on the top of atmosphere, in a physical framework of CR transportation. Two types of injection spectra are assumed, the broken power-law(BPL) form and the non-parametric spline interpolation form. The non-parametric form fits the data better than the BPL form, implying that potential structures beyond the constrained spectral shape of BPL may exist. For different nuclei the injection spectra are overall similar in shape but do show some differences among each other. For the non-parametric spectral form, the helium injection spectrum is the softest at low energies and the hardest at high energies. For both spectral shapes, the low-energy injection spectrum of neon is the hardest among all these species, and the carbon and oxygen spectra have more prominent bumps in 1–10 GV in the R2 d N dRpresentation.Such differences suggest the existence of differences in the sources or acceleration processes of various nuclei of CRs. 展开更多
关键词 (ISM:)cosmic rays acceleration of particles astroparticle physics
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The Historical Logic on the Basic Theory of Physics—A Summary on the Cosmic Continuum Theory
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作者 Xijia Wang 《Journal of Applied Mathematics and Physics》 2023年第3期823-840,共18页
Any scientific system has a unified basic theory. But physics has no unified basic theory in the modern sense. Classical mechanics, relativity and quantum mechanics have their own basic concepts, categories and princi... Any scientific system has a unified basic theory. But physics has no unified basic theory in the modern sense. Classical mechanics, relativity and quantum mechanics have their own basic concepts, categories and principles, so none of them can be regarded as true basic theories of physics. Cosmic Continuum Theory holds that the continuity and discreteness of the universe are fundamental issues related to the unification of physics. Because the contradiction between quantum non-locality and local reality is the fundamental obstacle to the unification of physics, while locality and non-locality correspond to the continuity and discreteness of physical reality respectively. The cosmic continuum theory introduces mathematical continuum and axiomatic ideas to reconstruct the basic theory of physics, and by the correspondence of existence and its dimensions to achieve the unification of the essence of physical reality, by introducing the cosmic continuum hypothesis to achieve the unification of the continuity and discreteness of physical reality, by introducing axiomatic methods to achieve formal unification of the foundations on physics. From the perspective of Cosmic Continuum, classical mechanics, relativity and quantum mechanics are no longer the basic theories of physics, but three branch theories of physics that are respectively applicable to macroscopic, cosmoscopic and microcosmic systems. 展开更多
关键词 cosmic Continuum Axiomatization of Physics Foundation of Physics Hilbert’s Problems Scientific Paradigm
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The Origin of Cosmic Microwave Background Radiation
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作者 Zhenglong Xu 《Journal of Modern Physics》 CAS 2023年第4期534-551,共18页
This paper explains the Olbers paradox and the origin of cosmic microwave background radiation (CMBR) from the viewpoint of the quantum redshift effect. The derived formula dispels the Olbers paradox, confirming that ... This paper explains the Olbers paradox and the origin of cosmic microwave background radiation (CMBR) from the viewpoint of the quantum redshift effect. The derived formula dispels the Olbers paradox, confirming that the CMBR originates from the superposition of light radiated by stars in the whole universe, not the relic of the Big Bang. The dark-night sky and CMBR are all caused by Hubble redshift—the physical mechanism is the quantum redshift of the photon rather than cosmic expansion. So this theory supports the infinite and steady cosmology. 展开更多
关键词 Olbers Paradox cosmic Microwave Background Radiation (CMBR) Big Bang Theory Hubble Redshift Quantum Redshift Effect of Photon Stefan-Boltzmann Law Blackbody Radiation
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