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L I Miroshnichenko - One of the best experts on this subject based on the ideXlab platform.
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Solar Cosmic Rays: 70 years of ground-based observations
2013Co-Authors: L I Miroshnichenko, E. V. Vashenyuk, J. A. Pérez-perazaAbstract:The main data have been summarized, and the results, achieved using data from the worldwide network during the entire period of ground-based observations of Solar Cosmic Rays (SCRs) from February 28, 1942, when they were discovered, have been generalized. The methods and equipment for registering SCRs have been described. The physical, methodical, and applied aspects, related to the SCR generation, as well as the SCR interaction with the Solar atmosphere, transport in the IMF, motion in the Earth’s magnetosphere, and the affect on the Earth’s atmosphere, have been discussed. It has been indicated that the fundamental results were achieved in this field of space physics during 70 years of studies. Special attention has been paid to up-to-date models and concepts of ground-level enhancement (GLE). The most promising tendencies in the development and application of this effective method of Solar-terrestrial physics have been outlined.
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electron and proton acceleration during the first ground level enhancement event of Solar cycle 24
2013Co-Authors: C Li, L I Miroshnichenko, Kazi A FirozAbstract:High-energy particles were recorded by near-Earth spacecraft and ground-based neutron monitors (NMs) on 2012 May 17. This event was the first ground level enhancement (GLE) of Solar cycle 24. In this study, we try to identify the acceleration source(s) of Solar energetic particles by combining in situ particle measurements from the WIND/3DP, GOES 13, and Solar Cosmic Rays registered by several NMs, as well as remote-sensing Solar observations from SDO/AIA, SOHO/LASCO, and RHESSI. We derive the interplanetary magnetic field (IMF) path length (1.25 +/- 0.05 AU) and Solar particle release time (01: 29 +/- 00: 01 UT) of the first arriving electrons by using their velocity dispersion and taking into account contamination effects. We found that the electron impulsive injection phase, indicated by the dramatic change in the spectral index, is consistent with flare non-thermal emission and type III radio bursts. Based on the potential field source surface concept, modeling of the open-field lines rooted in the active region has been performed to provide escape channels for flare-accelerated electrons. Meanwhile, relativistic protons are found to be released similar to 10 minutes later than the electrons, assuming their scatter-free travel along the same IMF path length. Combining multi-wavelength imaging data of the prominence eruption and coronal mass ejection (CME), we obtain evidence that GLE protons, with an estimated kinetic energy of similar to 1.12 GeV, are probably accelerated by the CME-driven shock when it travels to similar to 3.07 Solar radii. The time-of-maximum spectrum of protons is typical for shock wave acceleration.
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electron and proton acceleration during the first ground level enhancement of Solar cycle 24
2013Co-Authors: Kazi A Firoz, L P Sun, L I MiroshnichenkoAbstract:High-energy particles were recorded by near-Earth spacecraft and ground-based neutron monitors (NMs) on 2012 May 17. This event was the first ground level enhancement (GLE) of Solar cycle 24. In this study, we try to identify the acceleration source(s) of Solar energetic particles by combining in situ particle measurements from the WIND/3DP, GOES 13, and Solar Cosmic Rays registered by several NMs, as well as remote-sensing Solar observations from SDO/AIA, SOHO/LASCO, and RHESSI. We derive the interplanetary magnetic field (IMF) path length (1.25 +/- 0.05 AU) and Solar particle release time (01:29 +/- 00:01 UT) of the first arriving electrons by using their velocity dispersion and taking into account contamination effects. We found that the electron impulsive injection phase, indicated by the dramatic change in the spectral index, is consistent with flare non-thermal emission and type III radio bursts. Based on the potential field source surface concept, modeling of the open-field lines rooted in the active region has been performed to provide escape channels for flare-accelerated electrons.Meanwhile, relativistic protons are found to be released 10 minutes later than the electrons, assuming their scatter-free travel along the same IMF path length. Combining multi-wavelength imaging data of the prominence eruption and coronal mass ejection (CME), we obtain evidence that GLE protons, with an estimated kinetic energy of 1.12 GeV, are probably accelerated by the CME-driven shock when it travels to 3.07 Solar radii. The time-of-maximum spectrum of protons is typical for shock wave acceleration.
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astrophysical aspects in the studies of Solar Cosmic Rays
2008Co-Authors: L I Miroshnichenko, J PerezperazaAbstract:This review paper comprises main concepts, available observational data and recent theoretical results related to astrophysical aspects of particle acceleration at/near the Sun and extreme capacities of the Solar accelerator(s). We summarize underground and ground-based observations of Solar Cosmic Rays (SCR) accumulated since 1942, direct spacecraft measurements of Solar energetic particles (SEP) near the Earth's orbit, indirect information on the SCR variations in the past, and other relevant astrophysical, Solar and geophysical data. The list of the problems under discussion includes: upper limit spectrum (ULS) for Solar Cosmic Rays; maximum energy (rigidity), Em(Rm), of particles accelerated at/near the Sun; production of the flare neutrinos; energetics of SCR and Solar flares; production of flare neutrons and gamma Rays; charge states and elemental abundances of accelerated Solar ions; coronal mass ejections (CME's) and extended coronal structures in acceleration models; magnetic reconnection in acceleration scenarios; size (frequency) distributions of Solar proton events (SPE) and stellar flares; occurrence probability of giant flares; archaeology of Solar Cosmic Rays. The discussion allows us to outline a series of interesting conceptual and physical associations of SCR generation with the high-energy processes at other stars. The most reliable estimates of various parameters are given in each of research fields mentioned above; a set of promising lines of future studies is highlighted. A great importance of SCR data for resolving some general astrophysical problems is emphasized.
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Solar Cosmic Rays
2001Co-Authors: L I MiroshnichenkoAbstract:The first observations of Solar Cosmic Rays were made simultaneously by many investigators at worldwide Cosmic-ray stations in the periods of powerful chromospheric flares on February 28 and March 7, 1942. The discovery of these and the investigation of Cosmic-ray Solar-daily variations with maximum time near noon led some authors (Richtmyer and Teller, 1948; Alfven, 1949, 1950) to a model of apparent Cosmic-ray Solar origin. We present here the results of the properties of Solar Cosmic Rays from ground events (experimental and theoretical investigations). We also discuss important information from Solar experimental data relating to these ground events observed in September and October 1989 and May 1990. Some experimental evidence of acceleration processes in associated phenomena with flares and long-term (Solar cycle) variation of the average flux of Solar Cosmic Rays is discussed as also cornal and interplanetary propagation, and that in the terrestrial magnetosphere. Note that the energy spectrum of Solar Cosmic Rays varied very strongly from one flare to another. What are the causes of these phenomena? What is the nature of chemical and isotopic contents of Solar Cosmic Rays? How can its changes occur in the energy spectrum and chemical contents of Solar Cosmic Rays in the process of propagation? Is it possible to recalculate these parameters to the source? What makes Solar Cosmic Rays rich in heavy nucleus and3He? The important data about electrons, positrons, gamma-quanta and neutrons from flares will be discussed in a subsequent paper (Dorman and Venkatesan, 1992). The question is: What main acceleration mechanism of Solar flare and associated phenomena are reliable? These problems are connected with the more general problem on Solar flare origin and its energetics. In Dorman and Venkatesan (1993) we will consider these problems as well as the problem of prediction of radiation hazard from Solar Cosmic Rays (not only in space, but also in the Earth's atmosphere too).
R C Reedy - One of the best experts on this subject based on the ideXlab platform.
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measuring excitation functions needed to interpret cosmogenic nuclide production in lunar rocks
1997Co-Authors: J M Sisterson, K Kim, A Beverding, P A J Englert, Marc W Caffee, J Vincent, C Castaneda, R C ReedyAbstract:Radionuclides produced in lunar rocks by Cosmic ray interactions are measured using Accelerator Mass Spectrometry or gamma-ray spectroscopy. From these measurements, estimates of the Solar proton flux over time periods characterized by the half-life of the isotope under study can be made, if all the cross sections for all the reactions of all Cosmic ray particles with all elements found in lunar rocks are known. Proton production cross sections are very important because ∼98% of Solar Cosmic Rays and ∼87% of galactic Cosmic Rays are protons in the lunar environment. Many of the needed cross sections have never been measured. Targets of C, Al, Si, SiO2, Mg, K, Ca, Fe and Ni have been irradiated using three accelerators to cover a proton energy range of 25–500 MeV. Excitation functions for 7Be, 10Be, 22Na, and 26Al production from Mg and Al will be reported, and the consequences of using these new cross section values to estimate Solar proton fluxes discussed.
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measurement of proton production cross sections of sup 10 be and sup 26 al from elements found in lunar rocks
1996Co-Authors: J M Sisterson, P A J Englert, Marc W Caffee, A J T Jull, D J Donahue, L R Mchargue, J Vincent, C Castaneda, Kyeong Ja Kim, R C ReedyAbstract:Cosmic Rays penetrate the lunar surface and interact with the lunar rocks to produce both radionuclides and stable nuclides. Production depth profiles for long-lived radionuclides produce in lunar rocks are measured using Accelerator Mass Spectrometry (AMS). For a particular radionuclide these production depth profiles can be interpreted to give an estimate for the Solar proton flux over a time period characterized by the half life of the radionuclide under study. This analysis is possible if and only if all the cross sections for the interactions of all Cosmic ray particles with all elements found in lunar rocks are well known. In practice, the most important cross sections needed are the proton production cross sections, because 98% of Solar Cosmic Rays and {similar_to}87% of galactic Cosmic Rays are protons. The cross sections for the production of long-lived radionuclides were very difficult to measure before the development of AMS and only in recent years has significant progress been made in determining these essential cross sections. Oxygen and silicon are major constituents of lunar rocks. We have reported already {sup 14}C production cross sections from O and Si for proton energies 25-500 MeV, and O(p,x){sup 10}Be from 58 160 MeV[6]. Here we presentmore » new measurements for the cross sections O(p,x){sup 10}Be,O(p,x){sup 7}Be, Si(p,x){sup 7}Be,Si(p,x){sup 26}Al, and Si(p,x){sup 22}Na from {approximately}30 - 500 MeV.« less
J M Sisterson - One of the best experts on this subject based on the ideXlab platform.
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measurement of proton production cross sections of 10be and 26al from elements found in lunar rocks
1997Co-Authors: J M Sisterson, K Kim, A Beverding, P A J Englert, Marc W Caffee, A J T Jull, D J Donahue, L R Mchargue, C M Castaneda, J VincentAbstract:Cosmic Rays penetrate the lunar surface and interact with the lunar rocks to produce both radionuclides and stable nuclides. Production depth profiles for long-lived radionuclides produce in lunar rocks are measured using Accelerator Mass Spectrometry (AMS). For a particular radionuclide these production depth profiles can be interpreted to give an estimate for the Solar proton flux over a time period characterized by the half life of the radionuclide under study. This analysis is possible if and only if all the cross sections for the interactions of all Cosmic ray particles with all elements found in lunar rocks are well known. In practice, the most important cross sections needed are the proton production cross sections, because 98% of Solar Cosmic Rays and {similar_to}87% of galactic Cosmic Rays are protons. The cross sections for the production of long-lived radionuclides were very difficult to measure before the development of AMS and only in recent years has significant progress been made in determining these essential cross sections. Oxygen and silicon are major constituents of lunar rocks. We have reported already {sup 14}C production cross sections from O and Si for proton energies 25-500 MeV, and O(p,x){sup 10}Be from 58 160 MeV[6]. Here we present new measurements for the cross sections O(p,x){sup 10}Be,O(p,x){sup 7}Be, Si(p,x){sup 7}Be,Si(p,x){sup 26}Al, and Si(p,x){sup 22}Na from {approximately}30 - 500 MeV.
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measuring excitation functions needed to interpret cosmogenic nuclide production in lunar rocks
1997Co-Authors: J M Sisterson, K Kim, A Beverding, P A J Englert, Marc W Caffee, J Vincent, C Castaneda, R C ReedyAbstract:Radionuclides produced in lunar rocks by Cosmic ray interactions are measured using Accelerator Mass Spectrometry or gamma-ray spectroscopy. From these measurements, estimates of the Solar proton flux over time periods characterized by the half-life of the isotope under study can be made, if all the cross sections for all the reactions of all Cosmic ray particles with all elements found in lunar rocks are known. Proton production cross sections are very important because ∼98% of Solar Cosmic Rays and ∼87% of galactic Cosmic Rays are protons in the lunar environment. Many of the needed cross sections have never been measured. Targets of C, Al, Si, SiO2, Mg, K, Ca, Fe and Ni have been irradiated using three accelerators to cover a proton energy range of 25–500 MeV. Excitation functions for 7Be, 10Be, 22Na, and 26Al production from Mg and Al will be reported, and the consequences of using these new cross section values to estimate Solar proton fluxes discussed.
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measurement of proton production cross sections of sup 10 be and sup 26 al from elements found in lunar rocks
1996Co-Authors: J M Sisterson, P A J Englert, Marc W Caffee, A J T Jull, D J Donahue, L R Mchargue, J Vincent, C Castaneda, Kyeong Ja Kim, R C ReedyAbstract:Cosmic Rays penetrate the lunar surface and interact with the lunar rocks to produce both radionuclides and stable nuclides. Production depth profiles for long-lived radionuclides produce in lunar rocks are measured using Accelerator Mass Spectrometry (AMS). For a particular radionuclide these production depth profiles can be interpreted to give an estimate for the Solar proton flux over a time period characterized by the half life of the radionuclide under study. This analysis is possible if and only if all the cross sections for the interactions of all Cosmic ray particles with all elements found in lunar rocks are well known. In practice, the most important cross sections needed are the proton production cross sections, because 98% of Solar Cosmic Rays and {similar_to}87% of galactic Cosmic Rays are protons. The cross sections for the production of long-lived radionuclides were very difficult to measure before the development of AMS and only in recent years has significant progress been made in determining these essential cross sections. Oxygen and silicon are major constituents of lunar rocks. We have reported already {sup 14}C production cross sections from O and Si for proton energies 25-500 MeV, and O(p,x){sup 10}Be from 58 160 MeV[6]. Here we presentmore » new measurements for the cross sections O(p,x){sup 10}Be,O(p,x){sup 7}Be, Si(p,x){sup 7}Be,Si(p,x){sup 26}Al, and Si(p,x){sup 22}Na from {approximately}30 - 500 MeV.« less
J Vincent - One of the best experts on this subject based on the ideXlab platform.
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measurement of proton production cross sections of 10be and 26al from elements found in lunar rocks
1997Co-Authors: J M Sisterson, K Kim, A Beverding, P A J Englert, Marc W Caffee, A J T Jull, D J Donahue, L R Mchargue, C M Castaneda, J VincentAbstract:Cosmic Rays penetrate the lunar surface and interact with the lunar rocks to produce both radionuclides and stable nuclides. Production depth profiles for long-lived radionuclides produce in lunar rocks are measured using Accelerator Mass Spectrometry (AMS). For a particular radionuclide these production depth profiles can be interpreted to give an estimate for the Solar proton flux over a time period characterized by the half life of the radionuclide under study. This analysis is possible if and only if all the cross sections for the interactions of all Cosmic ray particles with all elements found in lunar rocks are well known. In practice, the most important cross sections needed are the proton production cross sections, because 98% of Solar Cosmic Rays and {similar_to}87% of galactic Cosmic Rays are protons. The cross sections for the production of long-lived radionuclides were very difficult to measure before the development of AMS and only in recent years has significant progress been made in determining these essential cross sections. Oxygen and silicon are major constituents of lunar rocks. We have reported already {sup 14}C production cross sections from O and Si for proton energies 25-500 MeV, and O(p,x){sup 10}Be from 58 160 MeV[6]. Here we present new measurements for the cross sections O(p,x){sup 10}Be,O(p,x){sup 7}Be, Si(p,x){sup 7}Be,Si(p,x){sup 26}Al, and Si(p,x){sup 22}Na from {approximately}30 - 500 MeV.
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measuring excitation functions needed to interpret cosmogenic nuclide production in lunar rocks
1997Co-Authors: J M Sisterson, K Kim, A Beverding, P A J Englert, Marc W Caffee, J Vincent, C Castaneda, R C ReedyAbstract:Radionuclides produced in lunar rocks by Cosmic ray interactions are measured using Accelerator Mass Spectrometry or gamma-ray spectroscopy. From these measurements, estimates of the Solar proton flux over time periods characterized by the half-life of the isotope under study can be made, if all the cross sections for all the reactions of all Cosmic ray particles with all elements found in lunar rocks are known. Proton production cross sections are very important because ∼98% of Solar Cosmic Rays and ∼87% of galactic Cosmic Rays are protons in the lunar environment. Many of the needed cross sections have never been measured. Targets of C, Al, Si, SiO2, Mg, K, Ca, Fe and Ni have been irradiated using three accelerators to cover a proton energy range of 25–500 MeV. Excitation functions for 7Be, 10Be, 22Na, and 26Al production from Mg and Al will be reported, and the consequences of using these new cross section values to estimate Solar proton fluxes discussed.
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measurement of proton production cross sections of sup 10 be and sup 26 al from elements found in lunar rocks
1996Co-Authors: J M Sisterson, P A J Englert, Marc W Caffee, A J T Jull, D J Donahue, L R Mchargue, J Vincent, C Castaneda, Kyeong Ja Kim, R C ReedyAbstract:Cosmic Rays penetrate the lunar surface and interact with the lunar rocks to produce both radionuclides and stable nuclides. Production depth profiles for long-lived radionuclides produce in lunar rocks are measured using Accelerator Mass Spectrometry (AMS). For a particular radionuclide these production depth profiles can be interpreted to give an estimate for the Solar proton flux over a time period characterized by the half life of the radionuclide under study. This analysis is possible if and only if all the cross sections for the interactions of all Cosmic ray particles with all elements found in lunar rocks are well known. In practice, the most important cross sections needed are the proton production cross sections, because 98% of Solar Cosmic Rays and {similar_to}87% of galactic Cosmic Rays are protons. The cross sections for the production of long-lived radionuclides were very difficult to measure before the development of AMS and only in recent years has significant progress been made in determining these essential cross sections. Oxygen and silicon are major constituents of lunar rocks. We have reported already {sup 14}C production cross sections from O and Si for proton energies 25-500 MeV, and O(p,x){sup 10}Be from 58 160 MeV[6]. Here we presentmore » new measurements for the cross sections O(p,x){sup 10}Be,O(p,x){sup 7}Be, Si(p,x){sup 7}Be,Si(p,x){sup 26}Al, and Si(p,x){sup 22}Na from {approximately}30 - 500 MeV.« less
E A Eroshenko - One of the best experts on this subject based on the ideXlab platform.
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Possible ground level enhancements of Solar Cosmic Rays in 2012
2015Co-Authors: A V Belov, E A Eroshenko, O N Kryakunova, N. F. Nikolayevskiy, A. M. Malimbayev, I. L. Tsepakina, V G YankeAbstract:It is commonly accepted that two ground level enhancements of Solar Cosmic Rays (GLEs) have so far been recorded in Solar cycle 24: one on May 17, 2012, and one on January 6, 2014. The current Solar activity cycle is considered to lag behind previous cycles in both quantity and magnitude of GLEs. Considerably more (around 30) Solar proton events have been recorded from satellites. In this work, we analyze the patterns of Cosmic ray intensity over the worldwide neutron monitor network during those events of 2012 in which considerable increases in the integral proton fluxes with energies of >100 MeV were observed, i.e., the events of January 27, March 7, and March 13, 2012. All of these events may be considered possible GLEs. More GLEs have apparently been observed during Solar cycle 24 than is widely recognized.
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intense ground level enhancements of Solar Cosmic Rays during the last Solar cycles
2011Co-Authors: M Andriopoulou, A V Belov, H Mavromichalaki, Christina Plainaki, E A EroshenkoAbstract:Ground-level enhancements of Solar Cosmic Rays are sharp increases of short duration in the counting rates of ground-based neutron monitors. Their study is of particular importance, mainly due to their involvement in a vast range of applications such as the prediction of particle fluxes that may be harmful for satellite systems and telecommunication, the analysis of the interplanetary conditions, and the prediction of strong geomagnetic storms. In this work, we make a statistical analysis of the ground-level enhancements events occurring during Solar Cycles 22 and 23, in an effort to reveal their common properties and possible physical mechanisms. Data of one- and five-minute resolutions are used, obtained from the worldwide network of neutron monitors and from the high-resolution NMDB database. The analysis includes onset-time calculations, determination of the maximum Cosmic ray intensity, and determination of the longitudinal and latitudinal distribution. Moreover, a brief description of the most intense events is given. Finally, the importance of such a statistical analysis in space weather studies is discussed.
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ground level enhancements of Solar Cosmic Rays during the last three Solar cycles
2010Co-Authors: A V Belov, E A Eroshenko, O N Kryakunova, V G Kurt, V G YankeAbstract:The catalog of ground level enhancements of Solar Cosmic Rays during cycles 21—23 of Solar activity has been presented. The main properties, time distribution, and relation of these events to Solar sources and proton enhancements observed on satellites have been studied.