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
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
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
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
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
We revisit the γ-ray emission above 300 Me V towards the massive star-forming region of Orion B by adopting14 yr observations with the Fermi Large Area Telescope and utilizing the updated software tools.The extended ...We revisit the γ-ray emission above 300 Me V towards the massive star-forming region of Orion B by adopting14 yr observations with the Fermi Large Area Telescope and utilizing the updated software tools.The extended γ-ray emission region around Orion B is resolved into two components(region Ⅰ and region Ⅱ).The γ-ray spectrum of region I agrees with the predicted γ-ray spectrum assuming the cosmic ray(CR)density is the same as that of Alpha Magnetic Spectrometer(AMS-02)measured locally.Theγ-ray emissivity of region II appears to be deficit at low energy band(E<3 GeV).Through modeling we find that CR densities exhibit a significant deficit below 20 Ge V,which may be caused by a slow diffusion inside the dense region.This is probably caused by an increased magnetic field whose strength increases with the gas density.展开更多
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
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
The author has suggested that the knee phenomenon in the cosmic ray energy spectrum at 3 PeV can be explained as a split between a radiation-dominated expansion and a matter-dominated expansion of an expanding heat ba...The author has suggested that the knee phenomenon in the cosmic ray energy spectrum at 3 PeV can be explained as a split between a radiation-dominated expansion and a matter-dominated expansion of an expanding heat bath. The model proposed in 1985, in fact, predicted that high energy cosmic rays are emitted from AGN, massive black holes, in agreement with recent data from the Pierre Auger Observatory. Similarly, the ankle phenomenon at 3 EeV is shown to be explained by a split between inflational expansion and ordinary material expansion of the expanding heat bath, not unlike that in the expansion of the universe. All the spectral indicies in the respective regions of the energy spectra agree with the theoretical calculation from the respective expansion rates. It is shown that the ankle energy is approximately equal to the threshold energy of cosmic ray production of an electron positron pair on the cmb photon.展开更多
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
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
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
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
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
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
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
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
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
A method of identifying positron/electron species from the cosmic rays was studied in the DArk Matter Particle Explorer(DAMPE)experiment.As there is no onboard magnet on the satellite,the different features imposed by...A method of identifying positron/electron species from the cosmic rays was studied in the DArk Matter Particle Explorer(DAMPE)experiment.As there is no onboard magnet on the satellite,the different features imposed by the geomagnetic field on these two species were exploited for the particle identification.Application of this method to the simulation of on-orbit electrons/positrons/protons and the real flight data proves that separately measuring the CR positrons/electrons with DAMPE is feasible,though limited by the field of view for the present observation data.Further analysis on the positron flux with this method can be expected in the future.展开更多
In recent years, many studies were published describing a wide scope of changes related to extreme (stormy) geomagnetic activity. In some countries, prediction of such days is a part of weather prediction information....In recent years, many studies were published describing a wide scope of changes related to extreme (stormy) geomagnetic activity. In some countries, prediction of such days is a part of weather prediction information. A number of risk factors like blood coagulation parameters, arterial blood pressure, inflammation markers, and some blood proteins were changing at days of GMA storms. Concomitant studies were published on an inverse phenomenon-increased cardiovascular event at days of Zero GMA, accompanied by high Space Neutron activity on the Earth’s surface—a marker of high Cosmic Ray activity. The aim of this study was to compare two groups of Acute Cardiovascular Events (ACE)—Acute Myocardial Infarction (AMI) and deaths from Ischemic Heart Disease (IHD) at days of extreme Cosmic Ray (CRA)-Neutron activity. Patients & methods: 4749 days at years 2000-2012 were studied considering ACE in a 3000 bed hospital in Kaunas, Lithuania. Cosmophysical data of this period was obtained from USA, Russia, and Finland. ACE was calculated at day of extreme High levels of CRA and following 48 hours. 13629 AMI and 3128 deaths from IHD were included. Results: It was a significant rise in AMI morbidity at day of high CRA (Neutron) activity (≥9300 imp/min). By analysis for each of gender, and patients age groups that were significant difference of AMI for all patients and male >65 y. old at Neutron activity ≥9400 imp/min (p = 0.048;p = 0.03), both gender > 65 y. old at Neutron activity >9500 (p = 0.078) and female >65 y. at Lag 2 (p = 0.07). For deaths from IHD, it was a significant rise at Neutron activity below 9300 imp/min (662 days (13.8%) were above the average of the full observation time-8935 ± 538.083)). Conclusion: At days of high CRA-Neutron activity, it was significantly more AMI. For IHD mortality was higher, but at lower Neutron activity—closer to average Neutron activity and higher GMA.展开更多
文摘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.
文摘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.
基金supported by the National Key Research and Development Program of China(No. 2021YFA0718404)the National Natural Science Foundation of China (No. 12220101003)the Project for Young Scientists in Basic Research of Chinese Academy of Sciences(No. YSBR-061)。
文摘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.
文摘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.
基金supported by the National Natural Science Foundation of China(Nos.12322302,12275279 and U1931201)the National Key R&D Program of China(No.2023YFE0102300)+2 种基金the Project for Young Scientists in Basic Research of Chinese Academy of Sciences(No.YSBR-061)the Chinese Academy of Sciencesthe Entrepreneurship and Innovation Program of Jiangsu Province。
文摘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.
基金supported by National Key R&D Program of China(grant No.2023YFE0117200)the National Natural Science Foundation of China(NSFC,grant Nos.12133003,12103011)+2 种基金R-Z.Y.is supported by the NSFC under grants 11421303,12041305Science and Technology Program of Guangxi(grant Nos.AD 21220075 and 2024GXNSFBA010375)the national youth thousand talents program in China。
文摘We revisit the γ-ray emission above 300 Me V towards the massive star-forming region of Orion B by adopting14 yr observations with the Fermi Large Area Telescope and utilizing the updated software tools.The extended γ-ray emission region around Orion B is resolved into two components(region Ⅰ and region Ⅱ).The γ-ray spectrum of region I agrees with the predicted γ-ray spectrum assuming the cosmic ray(CR)density is the same as that of Alpha Magnetic Spectrometer(AMS-02)measured locally.Theγ-ray emissivity of region II appears to be deficit at low energy band(E<3 GeV).Through modeling we find that CR densities exhibit a significant deficit below 20 Ge V,which may be caused by a slow diffusion inside the dense region.This is probably caused by an increased magnetic field whose strength increases with the gas density.
文摘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.
基金This work was supported by the National Natural Science Foundation of China(Nos.11705103 and 12005120).
文摘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.
文摘The author has suggested that the knee phenomenon in the cosmic ray energy spectrum at 3 PeV can be explained as a split between a radiation-dominated expansion and a matter-dominated expansion of an expanding heat bath. The model proposed in 1985, in fact, predicted that high energy cosmic rays are emitted from AGN, massive black holes, in agreement with recent data from the Pierre Auger Observatory. Similarly, the ankle phenomenon at 3 EeV is shown to be explained by a split between inflational expansion and ordinary material expansion of the expanding heat bath, not unlike that in the expansion of the universe. All the spectral indicies in the respective regions of the energy spectra agree with the theoretical calculation from the respective expansion rates. It is shown that the ankle energy is approximately equal to the threshold energy of cosmic ray production of an electron positron pair on the cmb photon.
文摘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.
文摘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.
文摘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.
文摘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.
文摘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.
基金supported by the National Natural Foundation of China(NSFC Grant No.11421303)the national youth thousand talents program in Chinasupported by the Fundamental Research Funds for the Central Universities。
文摘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.
基金Supported by the National Natural Science Foundation of China
文摘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.
基金supported by the State Key Project of Research and Development Plan (2016YFA0400204)the National Natural Science Foundation of China (U1738133)+3 种基金Strategic Pioneer Research Program in Space Science of the Chinese Academy of Science (CAS)Youth Innovation Promotion Association of CASMinistry of Science and Technology of Jiangsu Province (17KJD510001)Changzhou Institute of Technology (YN1611)
文摘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.
基金Supported by the National Natural Science Foundation of China under Grant No 11675187the Specialized Research Fund for State Key Laboratoriesthe CAS-TWAS President Fellowship Programme
文摘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.
基金supported by the Outstanding Youth Science Foundation of NSFC(Grant No.12022503)the Joint Funds of the National Natural Science Foundation of China(Grant Nos.U1738208,U1738139,U1738135 and U1738207)+2 种基金the National Natural Science Foundation of China(Grant Nos.11673021,11705197,11773085 and 11851302)the National Key Research and Development Program of China(Grant No.2016YFA0400200)Youth Innovation Promotion Association CAS(Grant No.2021450)。
文摘A method of identifying positron/electron species from the cosmic rays was studied in the DArk Matter Particle Explorer(DAMPE)experiment.As there is no onboard magnet on the satellite,the different features imposed by the geomagnetic field on these two species were exploited for the particle identification.Application of this method to the simulation of on-orbit electrons/positrons/protons and the real flight data proves that separately measuring the CR positrons/electrons with DAMPE is feasible,though limited by the field of view for the present observation data.Further analysis on the positron flux with this method can be expected in the future.
文摘In recent years, many studies were published describing a wide scope of changes related to extreme (stormy) geomagnetic activity. In some countries, prediction of such days is a part of weather prediction information. A number of risk factors like blood coagulation parameters, arterial blood pressure, inflammation markers, and some blood proteins were changing at days of GMA storms. Concomitant studies were published on an inverse phenomenon-increased cardiovascular event at days of Zero GMA, accompanied by high Space Neutron activity on the Earth’s surface—a marker of high Cosmic Ray activity. The aim of this study was to compare two groups of Acute Cardiovascular Events (ACE)—Acute Myocardial Infarction (AMI) and deaths from Ischemic Heart Disease (IHD) at days of extreme Cosmic Ray (CRA)-Neutron activity. Patients & methods: 4749 days at years 2000-2012 were studied considering ACE in a 3000 bed hospital in Kaunas, Lithuania. Cosmophysical data of this period was obtained from USA, Russia, and Finland. ACE was calculated at day of extreme High levels of CRA and following 48 hours. 13629 AMI and 3128 deaths from IHD were included. Results: It was a significant rise in AMI morbidity at day of high CRA (Neutron) activity (≥9300 imp/min). By analysis for each of gender, and patients age groups that were significant difference of AMI for all patients and male >65 y. old at Neutron activity ≥9400 imp/min (p = 0.048;p = 0.03), both gender > 65 y. old at Neutron activity >9500 (p = 0.078) and female >65 y. at Lag 2 (p = 0.07). For deaths from IHD, it was a significant rise at Neutron activity below 9300 imp/min (662 days (13.8%) were above the average of the full observation time-8935 ± 538.083)). Conclusion: At days of high CRA-Neutron activity, it was significantly more AMI. For IHD mortality was higher, but at lower Neutron activity—closer to average Neutron activity and higher GMA.