A Comparative Study of Ground-level Enhancement Events of Solar Energetic Particles
Major solar eruptions can accelerate protons up to relativistic energies. Solar relativistic ions arriving at 1 au may cause a solar particle event detectable by the worldwide network of neutron monitors (NMs), a ground-level enhancement (GLE) event. Using the newly computed NM yield function, we ha...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2023-01-01
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| Series: | The Astrophysical Journal |
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| Online Access: | https://doi.org/10.3847/1538-4357/acfee8 |
| _version_ | 1797613793028603904 |
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| author | Leon Kocharov Alexander Mishev Esa Riihonen Rami Vainio Ilya Usoskin |
| author_facet | Leon Kocharov Alexander Mishev Esa Riihonen Rami Vainio Ilya Usoskin |
| author_sort | Leon Kocharov |
| collection | DOAJ |
| description | Major solar eruptions can accelerate protons up to relativistic energies. Solar relativistic ions arriving at 1 au may cause a solar particle event detectable by the worldwide network of neutron monitors (NMs), a ground-level enhancement (GLE) event. Using the newly computed NM yield function, we have fitted the 15 historic GLEs. Moments of the fitted proton distributions are used for the analysis. Profiles of the proton net flux are very diverse, while some profiles are similar. For this study, we select two events with similar time profiles, GLE 60 (2001 April 15) and GLE 65 (2003 October 28), and ask what makes these GLEs similar. We compare the GLEs with their progenitor solar flares and coronal mass ejections (CMEs). We find a close relationship between the rise and peak of the GLE, on the one hand, and the solar flare and the metric radio emissions from extended coronal sources at the base of the CME, on the other hand. The GLE decay time, the rate of the proton spectrum evolution, and the CME speed are proportional to the duration of the soft X-ray flare. We compare the two GLEs with GLE 59 (2000 July 14) analyzed by Klein et al. and with the deka-MeV nucleon ^−1 proton and helium data from the ERNE instrument on the Solar and Heliospheric Observatory spacecraft. The comparison indicates that a single solar eruption can produce more than one component of solar energetic particles, differently contributing at different energies and locations. |
| first_indexed | 2024-03-11T06:59:39Z |
| format | Article |
| id | doaj.art-87dc6d0738c2484e85b17a008ee8a59e |
| institution | Directory Open Access Journal |
| issn | 1538-4357 |
| language | English |
| last_indexed | 2024-03-11T06:59:39Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj.art-87dc6d0738c2484e85b17a008ee8a59e2023-11-17T09:20:59ZengIOP PublishingThe Astrophysical Journal1538-43572023-01-01958212210.3847/1538-4357/acfee8A Comparative Study of Ground-level Enhancement Events of Solar Energetic ParticlesLeon Kocharov0https://orcid.org/0000-0002-2077-5618Alexander Mishev1Esa Riihonen2Rami Vainio3https://orcid.org/0000-0002-3298-2067Ilya Usoskin4https://orcid.org/0000-0001-8227-9081Sodankylä Geophysical Observatory, University of Oulu , Oulu 90014, FinlandSodankylä Geophysical Observatory, University of Oulu , Oulu 90014, Finland; Space Physics and Astronomy Research Unit, Faculty of Sciences, University of Oulu , Oulu 90014, FinlandSpace Research Laboratory, Department of Physics and Astronomy, University of Turku , Turku 20014, FinlandSpace Research Laboratory, Department of Physics and Astronomy, University of Turku , Turku 20014, FinlandSodankylä Geophysical Observatory, University of Oulu , Oulu 90014, Finland; Space Physics and Astronomy Research Unit, Faculty of Sciences, University of Oulu , Oulu 90014, FinlandMajor solar eruptions can accelerate protons up to relativistic energies. Solar relativistic ions arriving at 1 au may cause a solar particle event detectable by the worldwide network of neutron monitors (NMs), a ground-level enhancement (GLE) event. Using the newly computed NM yield function, we have fitted the 15 historic GLEs. Moments of the fitted proton distributions are used for the analysis. Profiles of the proton net flux are very diverse, while some profiles are similar. For this study, we select two events with similar time profiles, GLE 60 (2001 April 15) and GLE 65 (2003 October 28), and ask what makes these GLEs similar. We compare the GLEs with their progenitor solar flares and coronal mass ejections (CMEs). We find a close relationship between the rise and peak of the GLE, on the one hand, and the solar flare and the metric radio emissions from extended coronal sources at the base of the CME, on the other hand. The GLE decay time, the rate of the proton spectrum evolution, and the CME speed are proportional to the duration of the soft X-ray flare. We compare the two GLEs with GLE 59 (2000 July 14) analyzed by Klein et al. and with the deka-MeV nucleon ^−1 proton and helium data from the ERNE instrument on the Solar and Heliospheric Observatory spacecraft. The comparison indicates that a single solar eruption can produce more than one component of solar energetic particles, differently contributing at different energies and locations.https://doi.org/10.3847/1538-4357/acfee8Solar energetic particlesSolar flaresSolar radio flaresSolar x-ray flaresSolar coronal mass ejections |
| spellingShingle | Leon Kocharov Alexander Mishev Esa Riihonen Rami Vainio Ilya Usoskin A Comparative Study of Ground-level Enhancement Events of Solar Energetic Particles The Astrophysical Journal Solar energetic particles Solar flares Solar radio flares Solar x-ray flares Solar coronal mass ejections |
| title | A Comparative Study of Ground-level Enhancement Events of Solar Energetic Particles |
| title_full | A Comparative Study of Ground-level Enhancement Events of Solar Energetic Particles |
| title_fullStr | A Comparative Study of Ground-level Enhancement Events of Solar Energetic Particles |
| title_full_unstemmed | A Comparative Study of Ground-level Enhancement Events of Solar Energetic Particles |
| title_short | A Comparative Study of Ground-level Enhancement Events of Solar Energetic Particles |
| title_sort | comparative study of ground level enhancement events of solar energetic particles |
| topic | Solar energetic particles Solar flares Solar radio flares Solar x-ray flares Solar coronal mass ejections |
| url | https://doi.org/10.3847/1538-4357/acfee8 |
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