Mapping of the cosmic ray events related to the solar activity for the period 2003-2005

A. Papaioannou; P. Makrantoni; H. Mavromichalaki

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arXiv · 1009.5957

Mapping of the cosmic ray events related to the solar activity for the period 2003-2005

A. Papaioannou·P. Makrantoni·H. Mavromichalaki

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Abstract

The relationship between cosmic ray intensity decreases and solar events is still an open field of space research. In this work a complete study of solar events occurred from January 2003 to December 2005, is considered. This three-years time period characterized by an unexpected activity of the Sun was divided into 27-day intervals starting from BR 2313 (06.01.2003) to 2353 (21.12.2005), generating diagrams of the cosmic ray intensity data recorded at the Athens Neutron Monitor Station. This station is working at an altitude of 260m and cut-off rigidity 8.53GV provided to the Internet high-resolution data in real-time. A mapping of all available solar and interplanetary events, such as solar flares with importance M and X, coronal mass ejections (Halo and Partial) was done. As we are going down from the solar maximum to the declining phase of the 23rd solar cycle, a statistical overview of the corresponding relationship among these phenomena, the significant percentage of the connection of Halo CMEs and solar flares and the respective connection to Forbush decreases on yearly and monthly basis are discussed. The close association, as well as a probable quantitative analysis, between solar events is being denoted. The role of extreme solar events occurred in October / November 2003 and January 2005 is also discussed. Obtained results may be useful for predictions of transient solar events and space weather forecasting.

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A. Papaioannou, P. Makrantoni, H. Mavromichalaki. 2010-09-29. Mapping of the cosmic ray events related to the solar activity for the period 2003-2005. https://arxiv.org/abs/1009.5957

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