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Primordial black hole mass functions as a probe of cosmic origin

Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 164-171页

作者： Yi-Fu Cai Chengfeng Tang Geyu Mo Sheng-Feng Yan Chao Chen Xiao-Han Ma Bo Wang Wentao Luo Damien A.Easson Antonino Marcianò Deep Space Exploration Laboratory/School of Physical Sciences University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Researches in Galaxies and Cosmology/Department of Astronomy School of Astronomy and Space ScienceUniversity of Science and Technology of ChinaHefei 230026China Istituto Nazionale di Fisica Nucleare(INFN) Sezione di MilanoMilano 20146Italy DiSAT Universitàdegli Studi dell'InsubriaComo 22100Italy Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina Department of Physics Arizona State UniversityTempe 85287-1504USA Department of Physics&Center for Field Theory and Particle Physics Fudan UniversityShanghai 200433China Laboratori Nazionali di Frascati INFN Via Enrico Fermi 541 Frascati(Roma)00044Italy INFN sezione Roma Tor Vergata Rome I-00133Italy School of Physics University of Electronic Science and Technology of ChinaChengdu11731China

We discuss a novel window to probe the origin of our universe via the mass functions of primordial black holes(PBHs).The mass functions of PBHs are simply estimated using the conventional Press-Schechter formalism for two paradigms of cosmic origin,including inflationaryΛCDM and bounce cosmology.The standard inflationaryΛCDM model cannot generate an appreciable number of massive PBHs;however,non-trivial inflation models with blue-tilted power spectra at small scales and matter bounce cosmology provide formation mechanisms for heavy PBHs,which in turn,may seed the observed supermassive black holes(SMBHs).By fitting the SMBH mass functions at high redshift(z~6)derived from Sloan Digital Sky Survey(SDSS)and Canada-France High-z Quasar Survey(CFHQS)quasars,for two paradigms of cosmic origin,we derive constraints on the PBH density fraction fPBHat z~6 and the characteristic mass M_(★),with the prior assumption that all SMBHs stem from PBHs.We demonstrate that this newly proposed procedure,relying on astronomical measurements that utilize deep-field surveys of SMBHs at high redshift,can be used to constrain models of cosmic origin.Additionally,although not the main focus of this paper,we evolve the mass function from z~6 to z~0 through an assumption of 3×10^(8)-year Eddington’s accretion,and give a rough estimation of fPBHat z~0.

关键词： origin cosmic massive

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cosmic电离层掩星反演模拟及星座优化

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空间科学学报 2024年第1期44卷 71-79页

作者：许波波王成张雨露文援兰何丽娜李桢河海大学地球科学与工程学院南京211100 北京航空航天大学前沿科学技术创新研究院北京100191 北京航空航天大学电子信息工程学院北京100191

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... 详细信息

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.

关键词： cosmic 电离层掩星反演模拟电子密度

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Reconstruction using artificial intelligence,a promising way to explore the cosmic web

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 179-179页

作者： Houjun Mo Department of Astronomy University of MassachusettsAmherst MA 01003USA

One of the most important goals in modern cosmology is to understand the large-scale mass distribution of the universe(the cosmic web),and how galaxies form and evolve in the ecosystem of the cosmic web.Observationally this is done by large redshift surveys of galaxies,which can be used to trace the large-scale structure and to sample the properties of galaxies.

关键词： galaxies cosmic universe

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基于cosmic模型的宇宙射线中子反演荒漠-绿洲区土壤水分

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应用生态学报 2023年第9期34卷 2445-2452页

作者：吴绍雄张勇勇赵文智康文蓉田子晗中国科学院西北生态环境资源研究院临泽农田生态系统国家野外科学观测研究站兰州730000 中国科学院大学北京100049

宇宙射线中子技术通过监测近地面中子强度,反演百米尺度范围内平均土壤水分状况,已成功应用于森林、草地和农田等生态系统。为验证cosmic模型反演干旱区中尺度土壤水分的可靠性,本研究基于移动式宇宙射线中子技术在黑河中游荒漠-绿洲区... 详细信息

宇宙射线中子技术通过监测近地面中子强度,反演百米尺度范围内平均土壤水分状况,已成功应用于森林、草地和农田等生态系统。为验证cosmic模型反演干旱区中尺度土壤水分的可靠性,本研究基于移动式宇宙射线中子技术在黑河中游荒漠-绿洲区开展了土壤水分观测试验。结果表明:荒漠-绿洲区监测到的中子强度在350~715 counts·(30 s)^(-1),率定的高能中子强度(N_(cosmic))为(38.5±2.2) counts·(30 s)^(-1),N_(cosmic)受下垫面性质影响;cosmic模型(均方根误差RMSE=0.019 g·g^(-1))和N_(0)参数法(RMSE=0.018 g·g^(-1))均能较好地估算中尺度土壤水分,考虑矿物晶格水的情况下,土壤水的反演精度更高;试验期间,绿洲区平均有效监测深度为19 cm,荒漠区为36 cm。cosmic模型可用于荒漠-绿洲区宇宙射线中子反演土壤水分,结合陆面模型在实现近地面气象-水文-生态各要素数据同化方面具有较大潜力。

关键词：宇宙射线中子技术荒漠-绿洲土壤水分 cosmic 中尺度监测

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cosmic Dust in Suzhou A-Type Granite

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Science China Chemistry 1994年第9期37卷 1119-1129页

作者：王尔康万玉秋朱政胡中为林承毅周剑雄倪邦发 Department of Earth Sciences Nanjing University Nanjing 210008 PRC Department of Astronomy Nanjing University Nanjing 210008 PRC Centre for Modern Analysis Nanjing University Nanjing 210008 PRC Geological Academy of China Beijing 100037 PRC Institute of Atomic Energy of China Beijing 102413 PRC

A large number of microspherules have been extracted from Suzhou A-type granite bymeans of heavy placer.Both natural surfaces and part sections of 539 microspherules have been observed bySEM.457 microspherules have been determined by EDX,with some of them by EPMA,XRD and INAA.The results suggest these spherules are of ablated cosmic dust.Among them silicate glassy microspheruleshave been highly enriched in REE and other lithophile refractory trace elements,and REE abundance patternfavors a meteoritic origin as a roughly flat distribution.Ringwoodite has been first found in these glassy mi-crospherules.The composition of these iron spherules is similar to those of the ablated cosmic dust from deepsea and polar ice.Some Fe-Ni spherules and spherules composed of troilite have also been found.This isprobably the first report on various types of cosmic dust extracted from granite.

关键词： cosmic dust microspherule granite Suzhou

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Global Statistical Study of Ionospheric Waves Based on cosmic GPS Radio Occultation Data

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Chinese Physics Letters 2018年第10期35卷 93-97页

作者：曾炫云薛向辉乐新安贾铭蛟于秉坤吴建飞于超 CAS Key Laboratory of Geospace Environment School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 The Open University of Guangdong Guangzhou 51009 Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 College of Earth and Planetary Sciences University of Chinese Academy of Sciences Beijing 100049

Extracting and parameterizing ionospheric waves globally and statistically is a longstanding problem. Based on the multichannel maximum entropy method（MMEM） used for studying ionospheric waves by previous work, we calculate the parameters of ionospheric waves by applying the MMEM to numerously temporally approximate and spatially close global-positioning-system radio occultation total electron content profile triples provided by the unique clustered satellites flight between years 2006 and 2007 right after the constellation observing system for meteorology, ionosphere, and climate（cosmic） mission launch. The results show that the amplitude of ionospheric waves increases at the low and high latitudes（~0.15 TECU） and decreases in the mid-latitudes（~0.05 TECU）. The vertical wavelength of the ionospheric waves increases in the mid-latitudes（e.g., ~50 km at altitudes of 200–250 km） and decreases at the low and high latitudes（e.g., ~35 km at altitudes of 200–250 km）.The horizontal wavelength shows a similar result（e.g., ~1400 km in the mid-latitudes and ~800 km at the low and high latitudes）.

关键词： cosmic Global Statistical Study of Ionospheric Waves Based on cosmic GPS Radio Occultation Data GPS

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Implications on cosmic ray injection and propagation parameters from Voyager/ACE/AMS-02 nucleus data

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Science China(Physics,Mechanics & Astronomy) 2019年第4期62卷 98-105页

作者： Qiang Yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory Chinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China Center for High Energy Physics Peking University

We study the propagation and injection models of cosmic rays using the latest measurements of the boron-to-carbon ratio and fluxes of protons, helium, carbon, and oxygen nuclei by the Alpha Magnetic Spectrometer and the Advanced Composition Explorer at top of the Earth, and the Voyager spacecraft outside the heliosphere. The Advanced Composition Explorer(ACE) data during the same time interval of the AMS-02 data are extracted to minimize the complexity of the solar modulation effect. We find that the cosmic ray nucleus data favor a modified version of the diffusion-reacceleration scenario of the propagation. The diffusion coefficient is, however, required to increase moderately with decreasing rigidity at low energies, which has interesting implications on the particle and plasma interaction in the Milky Way. We further find that the low rigidity(cosmic rays.

关键词： cosmic rays propagation origin and acceleration data analysis

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Variability features of the width of the tropical belt from cosmic radio occultation data

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Science China Earth Sciences 2016年第4期59卷 795-802页

作者： GAO Pan ZHANG XiaoHong XU XiaoHua School of Geodesy and Geomatics Wuhan University Wuhan 430079 China Collaborative Innovation Center for Geospatial Technology Wuhan 430079 China

In this work, we analyzed time-series and trends of the tropical belt edges and widths with three methods based on the tropopause using new global positioning system radio occultation(GPS RO) data from the Constellation Observing System for Meteorology, Ionosphere, and Climate(cosmic) mission for September 2006–February 2014. The results from the three methods agreed well with previous studies and new features were found. To avoid the El Ni?o Southern Oscillation(ENSO) and Quasi-Biennial Oscillation(QBO) influence, we applied a simple multiple linear regression model to the monthly anomalies to obtain the tropical belt edges and width trends. During the study, we found equatorward movements of the tropical belt edges on both hemispheres. The narrowing of the tropical belt mainly occurred in the Pacific Ocean. We also found that the deseasonalized monthly anomalies of the tropical belt width were closely related with the ENSO and QBO. The tropical belt at a height of 15 km was mostly closely related with the ENSO. The correlations between the QBO and the tropical belt were consistent for the three methods.

关键词：无线电掩星 cosmic 热带宽度多元线性回归模型全球定位系统特征 ENSO

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Establishment of N_mF_2 empirical model in the northern hemisphere based on cosmic occultation data

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Science China(Technological Sciences) 2014年第2期57卷 339-344页

作者： NIU Jun FANG HanXian WENG LiBin Institution of Meteorology and Oceanography PLA University of Science and Technology State Key Laboratory of Space Weather Chinese Academy of Sciences

Ionospheric peak value of F2 layer(Nm F2)is an important parameter in the ionosphere,which has important applications in short-wave communication,ionospheric modeling and so on.In this paper,the empirical orthogonal function(EOF)decomposition method is used to analyze the Nm F2obtained from the occultation data.Daily spatial distribution of Nm F2at the same time is relatively even.Variance of first modal is much larger than the other modals.A local wavelet power spectrum(LWPS)method is applied to analysis the cycle of F10.7index and time coefficient of first modal.The result shows that they have similar cycle distribution,indicating that F10.7index is the main factor affecting variation of Nm F2.A function is established between the tine coefficient of first modal and F10.7index,average F10.7index value of early 81 days fp by least squares method.The results show that contribution coefficient of fp is negative which indicates that fp has an inert effect existing in the ionosphere.Contribution coefficient of F10.7is positive,which is consistent with the fact that it has an anomaly in winter/spring seasons.In summary,it is feasible to establish a mid-latitude empirical Nm F2model in northern hemisphere based on occultation data and EOF decomposition method.

关键词：电离层 cosmic 北半球模型掩星经验正交函数周期分布小波功率谱

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Determining Atmospheric Boundary Layer Height with the Numerical Differentiation Method Using Bending Angle Data from cosmic

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Advances in Atmospheric Sciences 2019年第3期36卷 303-312,340页

作者： Shen YAN Jie XIANG Huadong DU College of Meteorology and Oceanography National University of Defense Technology Key Laboratory of Mesoscale Severe Weather of Ministry of Education

This paper presents a new method to estimate the height of the atmospheric boundary layer(ABL) by using cosmic radio occultation bending angle(BA) data. Using the numerical differentiation method combined with the regularization technique, the first derivative of BA profiles is retrieved, and the height at which the first derivative of BA has the global minimum is defined to be the ABL height. To reflect the reliability of estimated ABL heights, the sharpness parameter is introduced, according to the relative minimum of the BA derivative. Then, it is applied to four months of cosmic BA data(January, April, July, and October in 2008), and the ABL heights estimated are compared with two kinds of ABL heights from cosmic products and with the heights determined by the finite difference method upon the refractivity data. For sharp ABL tops(large sharpness parameters), there is little difference between the ABL heights determined by different methods, i.e.,the uncertainties are small; whereas, for non-sharp ABL tops(small sharpness parameters), big differences exist in the ABL heights obtained by different methods, which means large uncertainties for different methods. In addition, the new method can detect thin ABLs and provide a reference ABL height in the cases eliminated by other methods. Thus, the application of the numerical differentiation method combined with the regularization technique to cosmic BA data is an appropriate choice and has further application value.

关键词：大气边界层高度数值微分方法 cosmic 弯角正则化

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