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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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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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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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On the Cosmic Ray Sources
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作者 Guido Pizzella 《Journal of Modern Physics》 2014年第5期244-247,共4页
The cosmic ray energy spectrum is calculated assuming that cosmic rays are generated by astrophysical objects provided by magnetospheres with a dipole magnetic field. With simple geometric considerations, the energy s... The cosmic ray energy spectrum is calculated assuming that cosmic rays are generated by astrophysical objects provided by magnetospheres with a dipole magnetic field. With simple geometric considerations, the energy spectrum E-2.5 is obtained, independently on the particle species. 展开更多
关键词 cosmic rayS
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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 Role of Atmospheric Pressure, Temperature, and Humidity on Cosmic Ray Muons at a Low Latitude Station
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作者 Abdullrahman H. Maghrabi Safia A. Alzahrani Aied S. Alruhaili 《International Journal of Astronomy and Astrophysics》 2023年第3期236-258,共23页
This study aimed to investigate the relationship between atmospheric conditions and cosmic ray (CR) muons using daily and monthly CR data collected by the KAAU muon detector in Jeddah, Saudi Arabia between 2007 and 20... This study aimed to investigate the relationship between atmospheric conditions and cosmic ray (CR) muons using daily and monthly CR data collected by the KAAU muon detector in Jeddah, Saudi Arabia between 2007 and 2012. Specifically, the study examined the effects of atmospheric pressure, air temperature, and relative humidity on CR muons at different time scales (annual, seasonal, and monthly). The results of the analysis revealed that atmospheric pressure and air temperature had a negative impact on CR muons, while relative humidity had a positive impact. Although air temperature and relative humidity had small mean values across all time scales, their coefficients varied significantly from month to month and season to season. In addition, the study conducted multivariable correlation analyses for each day, which showed that pressure coefficients had consistently negative mean values, while the temperature and humidity coefficients had varying effects, ranging from positive to negative values. The reasons for the variations in the coefficients are not yet fully understood, but the study proposed several possible terrestrial and extraterrestrial explanations. These findings provide important insights into the complex interactions between the Earth’s atmosphere and cosmic rays, which can contribute to a better understanding of the potential impacts of cosmic rays on the Earth’s climate and environment. 展开更多
关键词 cosmic rays Jeddah Atmospheric Effect High Rigidity MUONS
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Study on the Performance of the GRANDProto300 Particle Detector Array by Simulation
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作者 Fu-Lin Dai Quan-Bu Gou +1 位作者 Xiaoyuan Huang Yi-Qing Guo 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期173-177,共5页
The Giant Radio Array for Neutrino Detection(GRAND)is a proposed large-scale observatory designed to detect cosmic rays,gamma-rays,and neutrinos with energies exceeding 100 Pe V.The GRANDProto300 experiment is propose... The Giant Radio Array for Neutrino Detection(GRAND)is a proposed large-scale observatory designed to detect cosmic rays,gamma-rays,and neutrinos with energies exceeding 100 Pe V.The GRANDProto300 experiment is proposed as the early stage of the GRAND project,consisting of a hybrid array of radio antennas and scintillator detectors.The latter,as a mature and traditional detector,is used to cross-check the nature of the candidate events selected from radio observations.In this study,we developed a simulation software called G4GRANDProto300,based on the Geant4 software package,to optimize the spacing of the scintillator detector array and to investigate its effective area.The analysis was conducted at various zenith angles under different detector spacings,including 300,500,600,700,and 900 m.Our results indicate that,for large zenith angles used to search for cosmic-ray in the GRAND project,the optimized effective area is with a detector spacing of 500 m.The G4GRANDProto300 software that we developed could be used to further optimize the layout of the particle detector array in future work. 展开更多
关键词 astroparticle physics instrumentation:detectors (ISM:)cosmic rays
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The Effect of Spatial Structure Character of Heat Source on the Ray Path and the Evolution of Wave Energy of Meridional Wave Train
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作者 徐祥德 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第1期87-98,共12页
This paper studies correlations between the spatial structure character of thermal forcing and deformation and the amplitude of rays of meridional wave train. It is shown that if thermal forcing appears a meridional l... This paper studies correlations between the spatial structure character of thermal forcing and deformation and the amplitude of rays of meridional wave train. It is shown that if thermal forcing appears a meridional linear variation the rays of quasi-stationary planetary wave may propagate along oblique lines and if the meridional variability of heat source has second order term the rays show distinct deformation as a great circular route. Additionally, the inhomogeneous distribution may cause lower frequency oscillations in mid- and low-latitudes. The combination of zonal and meridional wave numbers and distributive character of heat source may form an inverse mechanism of variational trend of generized wave energy, reflecting in some degree the physical process of transition between meridional and zonal flow patterns. 展开更多
关键词 The Effect of Spatial Structure Character of Heat source on the ray Path and the Evolution of Wave Energy of Meridional Wave Train PATH Wave
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On-Site Calibration Method of Dosimeter Based on X-Ray Source
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作者 Wenhui Lv Huiping Guo +4 位作者 Ning Lv Chenyang Tian Kuo Zhao Xiaotian Wang Yijie Hou 《World Journal of Nuclear Science and Technology》 2017年第2期93-102,共10页
The real-time monitoring of environmental radiation dose for nuclear fa-cilities is an important part of safety, in order to guarantee the accuracy of the monitoring results regular calibration is necessary. Around nu... The real-time monitoring of environmental radiation dose for nuclear fa-cilities is an important part of safety, in order to guarantee the accuracy of the monitoring results regular calibration is necessary. Around nuclear facilities there are so many environmental dosimeters installed dispers-edly, because of its huge quantity, widely distributed, and in real-time monitoring state;it will cost lots of manpower and finance if it were tak-en to calibrate on standard laboratory;what’s more it will make the en-vironment out of control. To solve the problem of the measurement ac-curacy of the stationary gamma radiation dosimeter, an on-site calibra-tion method is proposed. The radioactive source is X-ray spectrum, and the dose reference instrument which has been calibrated by the national standard laboratory is a high pressure ionization. On-site calibration is divided into two parts;firstly the energy response experiment of dosim-eter for high and low energy is done in the laboratory, and the energy response curve is obtained combining with Monte Carlo simulation;sec-ondly experiment is carried out in the field of the measuring dosimeter, and the substitution method to calibrate the dosimeter is used;finally the calibration coefficient is gotten through energy curve correction. In order to verify the accuracy of on-site calibration method, the calibrated dosimeter is test in the standard laboratory and the error is 3.4%. The re-sult shows that the on-site calibration method using X-ray is feasible, and it can improves the accuracy of the measurement results of the stationary &gamma;-ray instrument;what’s more important is that it has great reference value for the radiation safety management and radiation environment evaluation. 展开更多
关键词 X ray source ON-SITE Calibration Energy Response GAMMA RADIATION DOSIMETER
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Dark Matter Particle Explorer: The First Chinese Cosmic Ray and Hard γ-ray Detector in Space 被引量:11
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作者 CHANG Jin 《空间科学学报》 CAS CSCD 北大核心 2014年第5期550-557,共8页
The Dark Matter Particle Explorer(DAMPE) mission is one of the five scientific space science missions within the framework of the Strategic Pioneer Program on Space Science of the Chinese Academy of Science(CAS) appro... The Dark Matter Particle Explorer(DAMPE) mission is one of the five scientific space science missions within the framework of the Strategic Pioneer Program on Space Science of the Chinese Academy of Science(CAS) approved in 2011. The main scientific objective of DAMPE is to detect electrons and photons in the range of 5 GeV–10 TeV with unprecedented energy resolution(1.5% at 100 GeV) in order to identify possible Dark Matter(DM) signatures. It will also measure the flux of nuclei up to above 500 TeV with excellent energy resolution(40% at 800 GeV), which will bring new insights to the origin and propagation high energy cosmic rays. With its excellent photon detection capability, the DAMPE mission is well placed for new discoveries in high energy-ray astronomy as well. 展开更多
关键词 DARK matter PARTICLE cosmic ray Electron GAMMA-ray
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Testing the effect of solar wind parameters and geomagnetic storm indices on Galactic cosmic ray flux variation with automatically-selected Forbush decreases 被引量:1
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作者 Jibrin Adejoh Alhassan Ogbonnaya Okike Augustine Ejikeme Chukwude 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第9期207-216,共10页
Forbush decrease(FD),discovered by Scott E.Forbush about 80 years ago,is referred to as the non-repetitive short-term depression in Galactic cosmic ray(GCR)flux,presumed to be associated with large-scale perturbations... Forbush decrease(FD),discovered by Scott E.Forbush about 80 years ago,is referred to as the non-repetitive short-term depression in Galactic cosmic ray(GCR)flux,presumed to be associated with large-scale perturbations in solar wind and interplanetary magnetic field(IMF).It is the most spectacular variability in the GCR intensity which appears to be the compass for investigators seeking solar-terrestrial relationships.The method of selection and validation of FD events is very important to cosmic ray(CR)scientists.We have deployed new computer software to determine the amplitude and timing of FDs from daily-averaged CR data at Oulu Neutron Monitor station.The code selected 230 FDs between 1998 and 2002.In an attempt to validate the new FD automated catalog,the relationship between the amplitude of FDs,and IMF,solar wind speed(SWS)and geomagnetic storm indices(Dst,kp,ap)is tested here.A two-dimensional regression analysis indicates significant linear relationship between large FDs(CR(%)≤-3)and solar wind data and geomagnetic storm indices in the present sample.The implications of the relationship among these parameters are discussed. 展开更多
关键词 methods:data analysis methods:statistical Sun:coronal mass ejections(CMEs) (Sun:)solar-terrestrial relations (Sun:)solar wind (ISM:)cosmic rays
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The Anisotropy of Cosmic Rays and the Global Anisotropy of Physical Space 被引量:1
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作者 Yuriy Alexeevich Baurov 《Journal of Modern Physics》 2012年第11期1744-1748,共5页
The influence of a new anisotropic factor onto the mechanism of accelerating cosmic rays up to ultrahigh energies (CR UHE) due to a new global natural force with the anisotropic behavior is considered. The directions ... The influence of a new anisotropic factor onto the mechanism of accelerating cosmic rays up to ultrahigh energies (CR UHE) due to a new global natural force with the anisotropic behavior is considered. The directions in the physical space along which CR UHE can arrive, are predicted. A brief comparative analysis of these directions together with the obtained experimental results is given. Their qualitative coincidences are shown. 展开更多
关键词 ANISOTROPY of cosmic rayS GLOBAL ANISOTROPY New FORCE
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First Observations of Cosmic Ray Neutrons by a Mini Neutron Monitor at Riyadh, Saudi Arabia 被引量:1
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作者 Maghrabi Abdullrahman Aldosari Abdulah Altilasi Mohammed 《International Journal of Astronomy and Astrophysics》 2020年第4期319-333,共15页
In April 2017, a mini neutron monitor (NM) was installed at King Abdulaziz City for Science and Technology (KACST) central Saudi Arabia (Riyadh;cut-off rigidity, Rc = 14.4 Gv) for continuous observation of the cosmic ... In April 2017, a mini neutron monitor (NM) was installed at King Abdulaziz City for Science and Technology (KACST) central Saudi Arabia (Riyadh;cut-off rigidity, Rc = 14.4 Gv) for continuous observation of the cosmic ray (CR) neutrons. The detector was built as a major aspect of the international scientific joint effort between the Centre of Space Research (North-West University, Potchefstroom, South Africa) and KACST. The recorded data correspond to low energy neutrons that primarily have energies lower than 20 GeV. In this paper, a brief description about the mini NM detector will be given. The influence of atmospheric pressure on the recorded CR neutrons was studied and the barometric coefficient was calculated and used to eliminate the pressure effects from the measured data. The obtained coefficient was consistent with those previously obtained by several investigators. The daily variation of the CR neutron was studied and characterized. Short-term CR periodicities, such as the 27-day period, and its two harmonics, were identified. The obtained periodicities are in agreement with those reported by different researchers. The obtained results from this detector have been compared to the existing 1 m<sup>2</sup> scintillator detector showing comparable results. Long-term data from this detector will be of incredible significance to the research community to investigate several types of CR variations resulting from solar activity at such high cut off rigidity site. 展开更多
关键词 Mini Neutron Monitor cosmic ray Saudi Arabia PERIODICITIES
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The Accurate Mass Formulas of Leptons, Quarks, Gauge Bosons, the Higgs Boson, and Cosmic Rays 被引量:2
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作者 Ding-Yu Chung 《Journal of Modern Physics》 2016年第12期1591-1606,共16页
One of the biggest unsolved problems in physics is the particle masses of all elementary particles which cannot be calculated accurately and predicted theoretically. In this paper, the unsolved problem of the particle... One of the biggest unsolved problems in physics is the particle masses of all elementary particles which cannot be calculated accurately and predicted theoretically. In this paper, the unsolved problem of the particle masses is solved by the accurate mass formulas which calculate accurately and predict theoretically the particle masses of all leptons, quarks, gauge bosons, the Higgs boson, and cosmic rays (the knees-ankles-toe) by using only five known constants: the number (seven) of the extra spatial dimensions in the eleven-dimensional membrane, the mass of electron, the masses of Z and W bosons, and the fine structure constant. The calculated masses are in excellent agreements with the observed masses. For examples, the calculated masses of muon, top quark, pion, neutron, and the Higgs boson are 105.55 MeV, 175.4 GeV, 139.54 MeV, 939.43 MeV, and 126 GeV, respectively, in excellent agreements with the observed 105.65 MeV, 173.3 GeV, 139.57 MeV, 939.27 MeV, and 126 GeV, respectively. The mass formulas also calculate accurately the masses of the new particle at 750 GeV from the LHC and the new light boson at 17 MeV. The theoretical base of the accurate mass formulas is the periodic table of elementary particles. As the periodic table of elements is derived from atomic orbitals, the periodic table of elementary particles is derived from the seven principal mass dimensional orbitals and seven auxiliary mass dimensional orbitals. All elementary particles including leptons, quarks, gauge bosons, the Higgs boson, and cosmic rays can be placed in the periodic table of elementary particles. The periodic table of elementary particles is based on the theory of everything as the computer simulation model of physical reality consisting of the mathematical computation, digital representation and selective retention components. The computer simulation model of physical reality provides the seven principal mass dimensional orbitals and seven auxiliary mass dimensional orbitals for the periodic table of elementary particles. 展开更多
关键词 Mass Formulas Particle Masses LEPTONS QUARKS Gauge Bosons Higgs Boson cosmic rays The Periodic Table of Elementary Particles Computer Simulation Knees-Ankles-Toe The Theory of Everything
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KELEA, Cosmic Rays, Cloud Formation and Electromagnetic Radiation: Electropollution as a Possible Explanation for Climate Change 被引量:1
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作者 W. John Martin 《Atmospheric and Climate Sciences》 2016年第2期174-179,共6页
The basic premise of this article is that human generated electromagnetic radiation is contributing to global warming. It may do so by diverting an energy force termed KELEA (kinetic energy limiting electrostatic attr... The basic premise of this article is that human generated electromagnetic radiation is contributing to global warming. It may do so by diverting an energy force termed KELEA (kinetic energy limiting electrostatic attraction) from its presumed association with cosmic rays. Cosmic ray delivered KELEA is viewed as normally participating in the formation of cloud condensation nuclei (CCN). It may do so by transforming electrostatically inert particles into electrostatic aerosols capable of acting as CCN. The resulting clouds act as a reflective barrier to some of the infrared radiation from the sun and, thereby, reduce the earth’s heat. This article proposes that increasing levels of electromagnetic radiation in the atmosphere is reducing the capacity of cosmic rays to deliver adequate KELEA to maintain climate stability through optimal cloud formation. Specifically, the fluctuating electrical fields accompanying electromagnetic radiation may do so by competitively withdrawing some of the KELEA from the incoming cosmic rays. Previously described studies by Dr. Wilhelm Reich attributed to an energy force termed orgone, are consistent with weather activity being inducible using a device that likely delivers KELEA to the atmosphere. In addition to the foregoing consideration, there are many agricultural and industrial applications of KELEA activated fluids that can reduce carbon emissions. It is important that the scope of climate science be broadened to include a detailed understanding of KELEA and of its many potential practical applications in addressing global warming. 展开更多
关键词 Climate Change CLOUD cosmic rays Electromagnetic Radiation KELEA Orgone WATER Cell Phone
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The low cosmic-ray density in the Polaris Flare
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作者 崔志伟 杨睿智 刘冰 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第10期46-50,共5页
We reported theγ-ray observation towards the giant molecular cloud Polaris Flare.Together with the dust column density map,we derived the cosmic ray(CR)density and spectrum in this cloud.Compared with the CR measured... We reported theγ-ray observation towards the giant molecular cloud Polaris Flare.Together with the dust column density map,we derived the cosmic ray(CR)density and spectrum in this cloud.Compared with the CR measured locally,the CR density in the Polaris Flare is significantly lower and the spectrum is softer.Such a different CR spectrum reveals either a rather large gradient of CR distribution in the direction perpendicular to the Galactic plane or a suppression of CR inside molecular clouds. 展开更多
关键词 cosmic rays gamma rays:ISM ISM:clouds
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TeV cosmic-ray proton and helium spectra in the myriad model Ⅱ
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作者 Wei Liu Pierre Salati Xuelei Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第1期15-27,共13页
Recent observations show that the spectra of cosmic ray nuclei start to harden above ~ 102 GeV, which contradicts the conventional steady-state cosmic ray model. We had suggested that this anomaly is due to the propa... Recent observations show that the spectra of cosmic ray nuclei start to harden above ~ 102 GeV, which contradicts the conventional steady-state cosmic ray model. We had suggested that this anomaly is due to the propagation effect of cosmic rays released from local young cosmic ray sources; the total flux of cosmic rays should be computed with the Myriad Model, where a contribution from sources in the local catalog is added to the background. However, although the hardening could be elegantly explained in this model, the model parameters obtained from the fit are skewed toward a region with fast diffusion and a low supernova rate in the Galaxy, in disagreement with other observations. We further explore this model in order to set up a concordant picture. Two possible improvements related to cosmic ray sources are considered. First, instead of the usual axisymmetric disk model, we examine a spiral model for the source distribution. Second, for nearby and young sources which are necessary to explain the hardening, we allow for an energy-dependent escape. We find that a major improvement comes from incorporating an energy-dependent escape time for local sources, and with both modifications not only are the cosmic ray proton and helium anomalies resolved, but also the parameters attain values in a reasonable range compatible with other analyses. 展开更多
关键词 catalogs cosmic rays pulsars: general galaxies: spiral
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Simulation study on cosmic ray background at large zenith angle based on GRANDProto35 coincidence array experiment
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作者 Xiang-Li Qian Xu Wang +2 位作者 Hui-Ying Sun Zhen Wang Olivier Martineau-Huynh 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第1期35-45,共11页
Neutrino detection in the 100 PeV energy region is the ultimate means of studying the origin of ultra-highenergy cosmic rays,in which the large radio detection array giant radio array for neutrino detection(GRAND)proj... Neutrino detection in the 100 PeV energy region is the ultimate means of studying the origin of ultra-highenergy cosmic rays,in which the large radio detection array giant radio array for neutrino detection(GRAND)project aims to use to decipher this century-old problem.The GRANDProto35 compact array is a microform of 35 radio prototype detectors for the GRAND experiment,which verifies the reliability of GRAND performance through operation,and data analysis of the prototype detectors.As radio detectors are a novel development in recent years,and their indexes need to be verified by traditional detectors,the GRAND Cooperation Group designed and constructed the GRANDProto35 coincidence array composed of radio detectors and scintillation detectors.This study simulated the changes in detection efficiency,effective area,and event rate of cosmic rays with zenith angle based on this coincidence array.The study found that the 1017 eV energy region is sensitive to GRANDProto35 detection.When the energy exceeded 1017 eV,the array detection efficiency could reach more than 95%and the effective area was up to*29106 m2.A simulation study on cosmic ray events with large zenith angles showed that the event rate detected by the array decreased significantly with increasing zenith angle,and the event rate of cosmic rays was approximately 0.1 per day for a zenith angle of 75.This serves as the background pollution rate for neutrino observation caused by largeangle cosmic-ray events,providing an important reference for further experiments.The study results will be verified after the joint operation of the coincidence array. 展开更多
关键词 GRANDProto35 GEANT4 Scintillation detector cosmic ray
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A machine learning method to separate cosmic ray electrons from protons from 10 to 100 GeV using DAMPE data
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作者 Hao Zhao Wen-Xi Peng +4 位作者 Huan-Yu Wang Rui Qiao Dong-Ya Guo Hong Xiao Zhao-Min Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第6期99-108,共10页
DArk Matter Particle Explorer(DAMPE) is a general purpose high energy cosmic ray and gamma ray observatory, aiming to detect high energy electrons and gammas in the energy range 5 Ge V to 10 Te V and hundreds of Te V ... DArk Matter Particle Explorer(DAMPE) is a general purpose high energy cosmic ray and gamma ray observatory, aiming to detect high energy electrons and gammas in the energy range 5 Ge V to 10 Te V and hundreds of Te V for nuclei. This paper provides a method using machine learning to identify electrons and separate them from gammas, protons, helium and heavy nuclei with the DAMPE data acquired from 2016 January 1 to 2017 June 30, in the energy range from 10 to 100 Ge V. 展开更多
关键词 astroparticle physics methods: data analysis cosmic rays
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Simulation of the Galactic Cosmic Ray Shadow of the Sun
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作者 Mohsin Saeed 查敏 曹臻 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第12期79-83,共5页
The cosmic-ray particles of TeV-regime, outside the solar system are blocked in their way to the Earth, a deficit of particles is observed corresponding to the location of the Sun known as the Sun shadow. The center o... The cosmic-ray particles of TeV-regime, outside the solar system are blocked in their way to the Earth, a deficit of particles is observed corresponding to the location of the Sun known as the Sun shadow. The center of the Sun shadow is shifted from its nominal position due to the presence of magnetic fields in interplanetary space,and this shift is used indirectly as a probe to study the solar magnetic field that is difficult to measure otherwise.A detailed Monte Carlo simulation of galactic cosmic-ray propagation in the Earth-Sun system is carried out to disentangle the cumulative effects of solar, interplanetary and geomagnetic fields. The shadowing effects and the displacements results of the Sun shadow in different solar activities are reproduced and discussed. 展开更多
关键词 Simulation of the Galactic cosmic ray Shadow of the Sun LHAASO IMF
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