Analysis of Solar Wind Parameters During Interplanetary Coronal Mass Ejections in September 2017

1. Quantification of solar wind parameters from measurments by SOHO and DSCOVR spacecrafts during series of Interplanetary Coronal Mass Ejections in the helioactive period September 2-15, 2017 • Tassev Y., P.I.Y. Velinov, D. Tomova*, A. Mishev** • Institute for Space Research and Technology, Bulgarian Academy of Sciences • * Sofia University, Faculty of Mathematics and Informatics, Sofia, Bulgaria • ** Space Climate Research Unit, University of Oulu, Finland

2. a b c Fig.1 a) and b) : Development of sunspot groups - Active Regions AR12673 and AR12674 for 24 hours -on September 2 and September 3. c) Visualization by the NLIL - NOAA (WSA) model of the first shock wave from CME and the second shock wave from the CME on September 6, from the sunspot group 2673 spreading to Earth.

3. Fig. 2 a) The event on September 10, 2017 in the interplanetary space and the third CME, accompanied by: b) powerful X-ray eruption class X8.2 at 16:06 UTC and c) radiation flux of high energy protons >= 10 MeV, >= 50 MeV and >= 100 MeV. a b c

4. Fig. 3 a) Impact on Earth and its magnetosphere; Kp indexes during the G4 Severe geomagnetic storm on September 7-8, 2017 b) Forbush decrease of Galactic Cosmic Rays caused by September 7th CME and Solar Cosmic Ray increase – i.e. the Ground Level Event № 72 (GLE72) caused by September 10th flare X8.2. c) GLE 72 by NM data

5. Fig. 4. Calculations of the solar wind parameters from measurments by SOHO and DSCOVR : the kinetic (dynamic) energy density Ek, thermal energy density Et and magnetic energy density Em during the investigated period September 2-15, 2017

6. THANK YOU