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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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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 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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New Probability Distributions in Astrophysics: VII. The Truncated Gamma-Pareto Distribution Applied to Cosmic Rays 被引量:1
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2022年第1期132-146,共15页
Many astrophysical phenomena are modeled by an inverse power law distribution at high values of the random variable but often at low values of the random variable we have a departure from an inverse power law. In orde... Many astrophysical phenomena are modeled by an inverse power law distribution at high values of the random variable but often at low values of the random variable we have a departure from an inverse power law. In order to insert a continuous transition from low to high values of the random variable we analyse the truncated gamma-Pareto distribution in two versions by deriving the most important statistical parameters. The application of the results to the distribution in energy of cosmic rays allows deriving an analytical expression for the average energy, which is 2.6 GeV. 展开更多
关键词 cosmic rays
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Ionization of protoplanetary disks by galactic cosmic rays,solar protons,and supernova remnants
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作者 Ryuho Kataoka Tatsuhiko Sato 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第2期247-252,共6页
Galactic cosmic rays and solar protons ionize the present terrestrial atmosphere,and the air showers are simulated by well-tested Monte-Carlo simulations,such as PHITS code.We use the latest version of PHITS to evalua... Galactic cosmic rays and solar protons ionize the present terrestrial atmosphere,and the air showers are simulated by well-tested Monte-Carlo simulations,such as PHITS code.We use the latest version of PHITS to evaluate the possible ionization of protoplanetary disks by galactic cosmic rays(GCRs),solar protons,and by supernova remnants.The attenuation length of GCR ionization is updated as 118 g cm^-2,which is approximately 20% larger than the popular value.Hard and soft possible spectra of solar protons give comparable and 20% smaller attenuation lengths compared with those from standard GCR spectra,respectively,while the attenuation length is approximately 10% larger for supernova remnants.Further,all of the attenuation lengths become 10% larger in the compound gas of cosmic abundance,e.g.128 g cm^-2 for GCRs,which can affect the minimum estimate of the size of dead zones in protoplanetary disks when the incident flux is unusually high. 展开更多
关键词 Galactic cosmic rays Solar protons Supernova remnants Young Sun Protoplanetary disk T Tauri stars
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Absence of the Impact of the Flux of Cosmic Rays and the Cloud Cover on the Energy Balance of the Earth
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作者 H.I.Abdussamatov 《Journal of Atmospheric Science Research》 2020年第3期1-7,共7页
The energy of solar radiation absorbed by the Earth,as well as the thermal radiation of the Earth’s surface,which is released to the space through the atmospheric transparency window,depends on variations of the area... The energy of solar radiation absorbed by the Earth,as well as the thermal radiation of the Earth’s surface,which is released to the space through the atmospheric transparency window,depends on variations of the area of the cloud cover.Svensmark et al.suggest that the increase in the area of the cloud cover in the lower atmosphere,presumably caused by an increase in the flux of galactic cosmic rays during the quasi-bicentennial minimum of solar activity,results only in an increase in the fraction of the solar radiation reflected back to the space and weakens the flux of the solar radiation that reached the Earth surface.It is suggested,without any corresponding calculations of the variations of the average annual energy balance of the EarthЕ,that the consequences will include only a deficit of the solar energy absorbed by the Earth and a cooling of the climate up to the onset of the Little Ice Age.These suggestions ignore simultaneous impact of the opposite aspects of the increase in the area of the cloud cover on the climate warming.The latter will result from a decrease in the power of thermal radiation of the Earth’s surface released to the space,and also in the power of the solar radiation reflected from the Earth’s surface,due to the increase in their absorption and reflection back to the surface.A substantial strengthening in the greenhouse effect and the narrowing of the atmospheric transparency window will also occur.Here,we estimate the impact of all aspects of possible long-term 2%growth of the cloud cover area in the lower atmosphere byЕ.We found that an increase in the cloud cover area in the lower atmosphere will result simultaneously both in the decrease and in the increase in the temperature,which will virtually compensate each other,while the energy balance of the Earth E before and after the increase in the cloud cover area by 2%will stay essentially the same:E1-E0≈0. 展开更多
关键词 CLIMATE cosmic rays Cloud Cover Energy Balance Little Ice Age Solar Irradiance Greenhouse Effect Atmospheric Transparency Window
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On the Relationship between Meteorological Variables, Dst Index, Solar Wind Speed, Solar Radio Flux, and Cosmic Rays and COVID-19 Cases
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作者 Maghrabi Abdullrahman 《Atmospheric and Climate Sciences》 CAS 2022年第3期517-531,共15页
This study aims to determine the influential role of the meteorological, solar, and geophysical factors and cosmic rays on the transmission of COVID-19 in Riyadh, Saudi Arabia. The meteorological factors were air temp... This study aims to determine the influential role of the meteorological, solar, and geophysical factors and cosmic rays on the transmission of COVID-19 in Riyadh, Saudi Arabia. The meteorological factors were air temperature, relative humidity, wind speed, and atmospheric pressure. The solar radio flux, Dst index, and solar wind speed were utilized as representatives of the solar and geophysical variables. The association between these variables and the COVID-19 pandemic cases from 3 April 2020 to 1 August 2021 was investigated using the Spearman and Kendall rank correlation tests. The obtained results showed that the air temperature and average wind speed are positively associated with the daily number of reported COVID-19 cases. On the other hand, the mean values of relative humidity and atmospheric pressure are inversely correlated with the number of COVID-19 cases in Riyadh. Moreover, the results showed that the Dst index and cosmic rays are positively correlated with the COVID-19 cases. Contrarily, solar wind speed and radio flux at 10.7 cm have negative correlations with the COVID-19 cases. The obtained results will help the epidemiologists to understand the behavior of the virus against meteorological, solar, and geophysical variables and can be considered as a useful supplement to help national and international organizations and healthcare policymakers in the process of strategizing to combat COVID-19. 展开更多
关键词 COVID-19 Solar Activity METEOROLOGY Space Weather cosmic rays
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Transport in Astrophysics: I. Diffusion of Solar and Galactic Cosmic Rays
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2022年第1期30-52,共23页
Some solutions for the diffusion phenomenon as a function of time and space are reviewed. Two new solutions of the homogeneous diffusion equation in 1D and 2D are derived in the presence of an existing fixed number of... Some solutions for the diffusion phenomenon as a function of time and space are reviewed. Two new solutions of the homogeneous diffusion equation in 1D and 2D are derived in the presence of an existing fixed number of particles. The initial conditions which allow deriving a power law behavior for the energy of the cosmic rays (CR) are derived. The superposition of transient diffusive phenomena on an existing power law distribution for the energy of CR allows simulating the knee, the second knee, and the ankle. 展开更多
关键词 cosmic rays Particle Diffusion Random Walks
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China Joins Hunt for Cosmic Rays
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作者 XIN Ling 《Bulletin of the Chinese Academy of Sciences》 2016年第3期133-133,共1页
On the beautiful Haizi Mountain 4,410 m above sea level in southwest China's Sichuan Province,construction work has begun on one of the world’s biggest and most sensitive cosmic ray detection facilities.Upon comp... On the beautiful Haizi Mountain 4,410 m above sea level in southwest China's Sichuan Province,construction work has begun on one of the world’s biggest and most sensitive cosmic ray detection facilities.Upon completion in 2020,the 1.2 billion yuan(180 million dollar)Large High Altitude Air Shower Observatory(LHAASO)will not only search for the sources of different types of 展开更多
关键词 LHAASO China Joins Hunt for cosmic rays
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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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An ACE/CRIS-observation-based Galactic Cosmic Rays heavy nuclei spectra model Ⅱ 被引量:2
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作者 Shuai Fu LingLing Zhao +2 位作者 Gary PZank Miao Wang Yong Jiang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2020年第1期100-111,共12页
An observation-based Galactic Cosmic Ray(GCR)spectral model for heavy nuclei is developed.Zhao and Qin[J.Geophys.Res.Space Phys.118,1837(2013)]proposed an empirical elemental GCR spectra model for nuclear charge 5≤z... An observation-based Galactic Cosmic Ray(GCR)spectral model for heavy nuclei is developed.Zhao and Qin[J.Geophys.Res.Space Phys.118,1837(2013)]proposed an empirical elemental GCR spectra model for nuclear charge 5≤z≤28 over the energy range^30 to 500 Me V/nuc,which is proved to be successful in predicting yearly averaged GCR heavy nuclei spectra.Based on the latest highly statistically precise measurements from ACE/CRIS,a further elemental GCR model with monthly averaged spectra is presented.The model can reproduce the past and predict the future GCR intensity monthly by correlating model parameters with the continuous sunspot number(SSN)record.The effects of solar activity on GCR modulation are considered separately for odd and even solar cycles.Compared with other comprehensive GCR models,our modeling results are satisfyingly consistent with the GCR spectral measurements from ACE/SIS and IMP-8,and have comparable prediction accuracy as the Badhwar&O’Neill 2014 model.A detailed error analysis is also provided.Finally,the GCR carbon and iron nuclei fluxes for the subsequent two solar cycles(SC 25 and 26)are predicted and they show a potential trend in reduced flux amplitude,which is suspected to be relevant to possible weak solar cycles. 展开更多
关键词 Galactic cosmic rays spectral model solar modulation heavy nuclei
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Nearby source interpretation of differences among light and medium composition spectra in cosmic rays 被引量:1
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作者 Qiang Yuan Bing-Qiang Qiao +2 位作者 Yi-Qing Guo Yi-Zhong Fan Xiao-Jun Bi 《Frontiers of physics》 SCIE CSCD 2021年第2期195-200,共6页
Recently the AMS-02 reported the precise measurements of the energy spectra of medium-mass compositions(Neon,Magnesium,Silicon)of primary cosmic rays,which reveal different properties from those of light compositions(... Recently the AMS-02 reported the precise measurements of the energy spectra of medium-mass compositions(Neon,Magnesium,Silicon)of primary cosmic rays,which reveal different properties from those of light compositions(Helium,Carbon,Oxygen).Here we propose a nearby source scenario,together with the background source contribution,to explain the newly measured spectra of cosmic ray Ne,Mg,Si,and particularly their differences from that of He,C,O.Their differences at high energies can be naturally accounted for by the element abundance of the nearby source.Specifically,the abundance ratio of the nearby source to the background of the Ne,Mg,Si elements is lower by a factor of~1.7 than that of the He,C,O elements.Such a diference could be due to the abundance difference of the stellar evolution of the progenitor star or the acceleration process/environment,of the nearby source.This scenario can simultaneously explain the high-energy spectral softening features of cos-mic ray spectra revealed recently by CREAM/NUCLEON/DAMPE,as well as the energy-dependent behaviors of the large scale anisotropies.It is predicted that the dipole anisotropy amplitudes below PeV energies of the Ne,Mg,Si group are smaller than that of the He,C,O group,which can be tested with future measurements. 展开更多
关键词 cosmic rays spectra and anisotropies
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COSMIC RAYS 被引量:1
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作者 K.A.Olive K.Agashe +208 位作者 C.Amsler M.Antonelli J.-F.Arguin D.M.Asner H.Baer H.R.Band R.M.Barnett T.Basaglia C.W.Bauer J.J.Beatty V.I.Belousov J.Beringer G.Bernardi S.Bethke H.Bichsel O.Biebe E.Blucher S.Blusk G.Brooijmans O.Buchmueller V.Burkert M.A.Bychkov R.N.Cahn M.Carena A.Ceccucci A.Cerr D.Chakraborty M.-C.Chen R.S.Chivukula K.Copic G.Cowan O.Dahl G.D'Ambrosio T.Damour D.de Florian A.de Gouvea T.DeGrand P.de Jong G.Dissertor B.A.Dobrescu M.Doser M.Drees H.K.Dreiner D.A.Edwards S.Eidelman J.Erler V.V.Ezhela W.Fetscher B.D.Fields B.Foster A.Freitas T.K.Gaisser H.Gallagher L.Garren H.-J.Gerber G.Gerbier T.Gershon T.Gherghetta S.Golwala M.Goodman C.Grab A.V.Gritsan C.Grojean D.E.Groom M.Grnewald A.Gurtu T.Gutsche H.E.Haber K.Hagiwara C.Hanhart S.Hashimoto Y.Hayato K.G.Hayes M.Heffner B.Heltsley J.J.Hernandez-Rey K.Hikasa A.Hocker J.Holder A.Holtkamp J.Huston J.D.Jackson K.F.Johnson T.Junk M.Kado D.Karlen U.F.Katz S.R.Klein E.Klempt R.V.Kowalewski F.Krauss M.Kreps B.Krusche Yu.V.Kuyanov Y.Kwon O.Lahav J.Laiho P.Langacker A.Liddle Z.Ligeti C.-J.Lin T.M.Liss L.Littenberg K.S.Lugovsky S.B.Lugovsky F.Maltoni T.Mannel A.V.Manohar W.J.Marciano A.D.Martin A.Masoni J.Matthews D.Milstead P.Molaro K.Monig F.Moortgat M.J.Mortonson H.Murayama K.Nakamura M.Narain P.Nason S.Navas M.Neubert P.Nevski Y.Nir L.Pape J.Parsons C.Patrignani J.A.Peacock M.Pennington S.T.Petcov Kavli IPMU A.Piepke A.Pomarol A.Quadt S.Raby J.Rademacker G.Raffel B.N.Ratcliff P.Richardson A.Ringwald S.Roesler S.Rolli A.Romaniouk L.J.Rosenberg J L.Rosner G.Rybka C.T.Sachrajda Y.Sakai G.P.Salam S.Sarkar F.Sauli O.Schneider K.Scholberg D.Scott V.Sharma S.R.Sharpe M.Silari T.Sjostrand P.Skands J.G.Smith G.F.Smoot S.Spanier H.Spieler C.Spiering A.Stahl T.Stanev S.L.Stone T.Sumiyoshi M.J.Syphers F.Takahashi M.Tanabashi J.Terning L.Tiator M.Titov N.P.Tkachenko N.A.Tornqvist D.Tovey G.Valencia G.Venanzoni M.G.Vincter P.Vogel A.Vogt S.P.Wakely W.Walkowiak C.W.Walter D.R.Ward G.Weiglein D.H.Weinberg E.J.Weinberg M.White L.R.Wiencke C.G.Wohl L.Wolfenstein J.Womersley C.L.Woody R.L.Workman A.Yamamoto W.-M.Yao G.P.Zeller O.V.Zenin J.Zhang R.-Y.Zhu F.Zimmermann P.A.Zyla G.Harper V.S.Lugovsky P.Schaffner 《Chinese Physics C》 SCIE CAS CSCD 2014年第9期378-385,共8页
Revised October 2013 by J.J. Beatty (Ohio State Univ.), J. Matthews (Louisiana State Univ.), and S.P. Wakely (Univ. of Chicago); revised August 2009 by T.K. Gaisser and T. Stanev (Bartol Research Inst., Univ. o... Revised October 2013 by J.J. Beatty (Ohio State Univ.), J. Matthews (Louisiana State Univ.), and S.P. Wakely (Univ. of Chicago); revised August 2009 by T.K. Gaisser and T. Stanev (Bartol Research Inst., Univ. of Delaware). 展开更多
关键词 cosmic rays
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Spatial dependent diffusion of cosmic rays and the excess of primary electrons derived from high precision measurements by AMS-02
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作者 靳超 郭义庆 胡红波 《Chinese Physics C》 SCIE CAS CSCD 2016年第1期60-64,共5页
The precise spectra of Cosmic Ray (CR) electrons and positrons have been published by the measurement of AMS-02. It is reasonable to regard the difference between the electron and positron spectra (△Ф=Фe- -Фe+... The precise spectra of Cosmic Ray (CR) electrons and positrons have been published by the measurement of AMS-02. It is reasonable to regard the difference between the electron and positron spectra (△Ф=Фe- -Фe+) as being dominated by primary electrons. The resulting electron spectrum shows no sign of spectral softening above 20 GeV, which is in contrast with the prediction of the standard model of CR propagation. In this work, we generalize the analytic one-dimensional two-halo model of diffusion to a three-dimensional realistic calculation by implementing spatial variant diffusion coefficients in the DRAGON package. As a result, we can reproduce the spectral hardening of protons observed by several experiments, and predict an excess of high energy primary electrons which agrees with the measurement reasonably well. Unlike the break spectrum obtained for protons, the model calculation predicts a smooth electron excess and thus slightly over-predicts the flux from tens of GeV to 100 GeV. To understand this issue, further experimental and theoretical studies are necessary. 展开更多
关键词 cosmic rays primary electron EXCESS DIFFUSION PROPAGATION HARDENING
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Study on the separation of 100 TeV γ-rays from cosmic rays for the Tibet ASγ experiment
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作者 冯朝阳 张毅 +7 位作者 刘成 樊超 李红超 王博 吴含荣 胡红波 卢红 谭有恒 《Chinese Physics C》 SCIE CAS CSCD 2011年第2期153-157,共5页
A γhadron separation analysis is described for the observed air shower events with primary energy above 100 TeV based on the Tibet ASγ detector configuration. The shower age and size parameters are fitted from the m... A γhadron separation analysis is described for the observed air shower events with primary energy above 100 TeV based on the Tibet ASγ detector configuration. The shower age and size parameters are fitted from the measured lateral density distribution and used as discrimination variables. According to the MC simulation while taking into account the systematic uncertainty estimated from data and MC comparison, it is found that 70% of the cosmic ray (CR) background can be rejected while more than 78% of the T-rays can be retained. Sensitivity for 100 TeV γ-rays observation can thus be improved by at least 40%. 展开更多
关键词 origin of cosmic rays 100 TeV γ-rays emission Tibet AST experiment NKG-function
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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 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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On the knee of Galactic cosmic rays in light of sub-TeV spectral hardenings
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作者 郭义庆 袁强 《Chinese Physics C》 SCIE CAS CSCD 2018年第7期113-122,共10页
More than fifty years after the discovery of the knee in the cosmic ray (CR) spectra, its physical origin remains a mystery. This is partly due to the ambiguity of the energy spectra of individual components. Recent... More than fifty years after the discovery of the knee in the cosmic ray (CR) spectra, its physical origin remains a mystery. This is partly due to the ambiguity of the energy spectra of individual components. Recently, direct measurements from several space experiments found significant spectral hardenings of CR nuclei at ~200 GV. A joint modeling of the direct and indirect measurements may help to understand the experimental systematics and the physics of the knee. In this work, we update the phenomenological "poly-gonato" model to include the spectral hardenings, with a changing spectral index of γ + β·logE. This modification gives a reasonable description of the CR spectra in a wide energy range. However, the fits to different data sets give different results. We find that the fit to the AMS-02 and CREAM data slightly favors a relatively low energy knee of the light components. In such a case, the expected all-particle spectra under-shoot the data, which may require an extra component of CRs. The fits to AMS-02 data and the light component (H+He) data from the Tibet ASγ/ARGO-YBJ/WFCTA and KASCADE experiments give consistent results with the all-particle spectra. We further propose a possible physical realization of such a "modified poly-gonato" model of spectral hardenings by means of spatially-dependent diffusion of CRs. We find reasonably good agreement between the model predictions and the data for CR spectra, the secondary-to-primary ratios, and the amplitude of anisotropies. 展开更多
关键词 cosmic ray KNEE SPECTRUM PROPAGATION
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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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