Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 48869 10.12737/stp-82202204 Results of current research Results of current research Results of current research Pitch-angle anisotropy and differential rigidity spectra of cosmic rays during GLE on May 2 and 6, 1998 Pitch-angle anisotropy and differential rigidity spectra of cosmic rays during GLE on May 2 and 6, 1998 Луковникова Анна Александровна Lukovnikova Anna Aleksandrovna luk@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Сдобнов Валерий Евгеньевич Sdobnov Valeriy Evgen'evich sdobnov@iszf.irk.ru

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation 30 06 2022 30 06 2022 8 2 26 30 09 02 2022 01 04 2022 https://naukaru.ru/en/nauka/article/48869/view

Using data from the worldwide network of neutron monitors (39 stations) and the method of global spectrographic survey, we have studied pitch-angle anisotropy and differential rigidity spectra of cosmic rays during the ground level enhancements on May 2 and 6, 1998. We obtained differential rigidity spectra of solar cosmic rays in these events and determined the maximum rigidities to which protons accelerated. The maximum rigidities of accelerated protons during the ground level enhancements on May 2 was ~2.4; on May 6, ~1.8 GV. The revealed bidirectional pitch-angle anisotropy indicates that Earth was in the IMF loop structure during these events.

Using data from the worldwide network of neutron monitors (39 stations) and the method of global spectrographic survey, we have studied pitch-angle anisotropy and differential rigidity spectra of cosmic rays during the ground level enhancements on May 2 and 6, 1998. We obtained differential rigidity spectra of solar cosmic rays in these events and determined the maximum rigidities to which protons accelerated. The maximum rigidities of accelerated protons during the ground level enhancements on May 2 was ~2.4; on May 6, ~1.8 GV. The revealed bidirectional pitch-angle anisotropy indicates that Earth was in the IMF loop structure during these events.

 cosmic rays ground level enhancement anisotropy rigidity spectrum cosmic rays ground level enhancement anisotropy rigidity spectrum The work was financially supported by the Ministry of Science and Higher Education of the Russian Federation The work was financially supported by the Ministry of Science and Higher Education of the Russian Federation

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