Relation between Solar Activity Features and Geomagnetic Activity Indices during Cycle-24

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1 Corona Journal of Science and Technology ISSN : (Online), Vol. 4, No. III (215), pp. Publication Relation between Solar Activity Features and Geomagnetic Activity Indices during Cycle-24 Balveer S Rathore, K K Parashar, Rammohan S Bhadoria, Neetu Sikarwar and Dinesh C Gupta Abstract: In this paper we find relation between solar activity and geomagnetism during the solar cycle-24. Geomagnetic storms were less during the current cycle, no severe and great storms are occurred during this cycle.ly occurrence of Geomagnetic Storms does not exactly match with phase of current solar cycle. Similarly occurrences of Halo CMEs also do not follow the phase of solar cycle exactly whereas yearly occurrence of Geomagnetic Storms follows the yearly occurrence of Halo CMEs. Consequently, halo CMEs are responsible for the occurrence of Geomagnetic Storms during the solar cycle-24. The correlation between Solar flares and Geomagnetic Storms are found good with M and X-class flares. Therefore it s clear from present study Solar flare may also a possible cause of Geomagnetic Storms with Coronal mass ejections. Keywords: Solar Cycle, Geomagnetic Storm, Sun Spots, Solar Flare and Coronal mass ejection (CME) etc. 1. INTRODUCTION Sun and solar activities play an important role in space weather variation. It was investigated in previous studies sun spots are causes of change of earth environment. The 11-year solar activity cycle has been an open question since long time and various investigators have addressed this problem. The solar activity is directly related to space weather while geomagnetic activity rises and fall along with the solar activity. It has also investigated major geomagnetic storms (GMSs) are associated with solar flares and coronal mass ejections (CMEs) and ultimately GMSs are depend on solar activities. Researchers (Rathore et al, 212) have worked on last solar cycle and report that, solar cycle-23 was start from 1996 and ended at 27. Balveer S Rathore, Assistant Professor, Lakshmi Narain College of Tecnology (LNCT), Bhopal, balveer_singhra@yahoo.co.in. Dinesh C Gupta, Associative Professor, School of Studies in Physics, Jiwaji University, Gwalior (India). Rammohan S Bhadoria, Research Scholar, School of Studies in Physics, Jiwaji University, Gwalior (India). K K Parashar, Research Scholar, School of Studies in Physics, Jiwaji University, Gwalior (India). It is observed that, in the whole period of solar cycle-23, the solar cycle contained one maximum peak, where sunspot number is largest and period of that peak is termed as solar maximum activity phase. The maximum phase of solar cycle-23 has been measured during the year 2, whereas the periods and 21-7 are the periods of minimum phase of solar activity (Rathore et al, 211; Rathore et al, 212). They have been observed that inference of geomagnetic storm with corresponding sun spot numbers during cycle-23. Shrivastava et al (Shrivastava et al, 29) has observed the Coronal mass ejection (CME) activity and reported that it should follow, rather closely to the sunspot cycle, but the correlation in exact counts may not be precise. This is probably because CMEs happen in layers of the sun that are much higher above the solar surface than the sunspots. Gopalswamy (Gopalswamy, 211) have investigated around ~14 CMEs, which has occurred during the span of cycle-23, with an average rate of 11 CMEs per year. But it is interesting that all CMEs were not geoeffective. Furthermore, one of the interesting features of the bright CMEs had a width of 36, such CMEs are known as halo CMEs. Halo CMEs directly impact on the earth magnetosphere and produce GMSs. Earlier works that investigated the relation between CMEs and GMSs concentrated mainly on the interplanetary counterparts of CMEs (Interplanetary CMEs) without paying much attention to the CMEs near the sun (Rathore et al, 211). Out of different types of CME, Halo CMEs are more likely to impact the earth and shot-out at right angle to the sunearth line. After Carrington (Carrington, 186), Chapman and Ferraro (Chapman et al, 193) gave the detail explanation of the phenomena of geomagnetic storms and their association with flares. They argued that whenever the Sun emits a solar flare it will also emit plasma cloud. This plasma cloud reaches the Earth and compresses the Earth s magnetic field and thus increases this magnetic field and so increases this magnetic field at the Earth s surface (Jain et al, 26, Jain et al, 28).

2 Sun Spots Number Geomagnetic Storms (GMS's) 1.2 DATA COLLECTION Cycle-24 has been taken for present study, which start from 28. Geomagnetic storms condition data (Dst- Disturb storm time) has been taken from Kyoto Japan. Dst have the indicator of geomagnetic storm, here we have taken a critical value of Dst -5 nt during the cycle-24. A Sun spot data has been taken from omniweb.gfsc.nasa.gov. A list of CMEs is provided by CDAW-NASA s centre to maintain these CMEs data. In the present study solar flares data has been taken from RHESSI. 1.3 RESULT AND DISCUSSION Good correlation has been found between solar activity and geomagnetic condition during the last cycle. It s expected that, the year 212 will be the highly stormy year in next solar cycle-24. With this prediction, the study of current cycle-24 becomes important. In present study we take cycle-24. ly occurrence of sunspots (SSNs), geomagnetic storms (GMSs) and Halo CMEs are given in table-1. Table-1: Average number of Sun spots (SSNs) per year, total number of Geomagnetic storms (GMSs) per year and Halo CMEs during SSNs GMSs Halo CMEs In the present work, the data of sun spots were collected from world data centre. ly average of sun spots data during cycle-24 has been taken, which started from 28, as is shown in figure-1. It is observed that, in the whole period of solar cycle-24, the solar cycle contained one maximum peak, where sunspot number is largest and the period of that peak is termed as solar maximum activity phase. The maximum phase of solar cycle-24 has been measured during the year 213, whereas the periods are the periods of rising minimum phase of solar activity. The current studies for Sunspot Cycle 24 gives a smoothed sunspot number, maximum of about 98 in the 213. The smoothed sunspot number has already reached 92, the strong peak in 211 before 213. The smoothed sunspot number has been raised again towards a second peak over the year 213. Effect of variation of sun spots on earth magnetic atmosphere are indicated in term of Geomagnetic storms. In the present study the Disturbance storm time (Dst) index is used to identify the geomagnetic storms which occurred in time interval 28 to 213. Total 47 geomagnetic storms observed during the span of solar cycle 24 with Dst -5 nt. Using the minimum Dst value as an indicator, we have classified the storms as moderate (36), strong (11), severe (), and great () has found during the cycle SSN's GMS's Fig. 1: Average number of sun spots per year and the total number of storm days per year during The large numbers of geomagnetic storms occurred in 211 and 213. It is found that maximum number of geomagnetic storms has occurred during 212, while year 213 was the maxima of the solar cycle-24. Therefore, geomagnetic storms do not follow the phase of solar cycle exactly and shows complex behavior as the last cycle. It is believed that the no severe geomagnetic storms have occurred during sunspot cycle-24. It has been observed the solar cycle-24 quite opposite according to initial expectation. We are currently over five years into Cycle 24. The current predicted and observed size makes this the smallest sunspot cycle since Cycle 14 which had a maximum of 64.2 in 196. Sun spots are not a possible cause of geomagnetic storms. Further we analyzed solar activity Coronal mass ejection and Solar flares in the present work, we analyzed about 184 Halo CMEs, which have occurred during the solar cycle-24 and recorded by space borne high resolution cameras on board SOHO-LASCO and other spacecrafts too. (8)

3 Sun Spots Number (SSN's) Halo CMEs Halo CMEs Geomagnetic Storms (GMS's) About 184 halo CMEs has been occurred during period The number of Halo CMEs observed in each year along with the SSNs is shown in figure SSNs Halo CMEs Fig. 2: Average number of Halo CME per year and the total number of SSNs per year during solar cycle-24. After a critical observation it is evident that in year 28 and 29 only 1 Halo CMEs are occurred. The year 28 and 29 represents minimum sunspot activity during ascending phase of solar cycle 24. It is also found that large numbers of Halo CMEs have occurred in years 212 and 213. But in year 212 occurrence of halo CME was large but number of Sunspots was less than year 213. Thus, it clearly indicates that occurrence of Halo CMEs do not follow the phase of solar cycle exactly. These results similar like last cycle by rathore et al., (rathore, 212) in the next figure shows occurrence of geomagnetic storms (GMSs) with halo CME in figure-3. It is explicitly clear from the figure-2 that the GMS were large during the maximum phase of solar cycle-24. It is cleared from figure-3 that the GMSs are exactly following the occurrence rate of Halo CMEs. Thus, we can conclude that Halo CMEs are the possible cause of GMSs during the cycle-24. The present results match with earlier finding and substantiate these observations Halo CME's Fig. 3: Average number of Halo CME per year and the total number of storm days per year during solar cycle- 24. In the present study solar flares data has been taken from RHESSI. In Table-2 are shown all categories flares data which have been taken from RHESSI during the year 29 to 213 period of solar cycle-24 along with GMSs. In table-2 shows, flares data during the cycle-24. Table-2: Shows yearly occurrence of solar flares during cycle-24 Flare #B #C #M #X GMSs In the figure-4 shows that total number of flares during the year A correlation has been found between solar flares and GSMs. This shows in figures. (9)

4 Geomagnetic Storms (GMS's) C-type Flares Number of Flare B-type Flares r = Fig. 4: Average number of Flares per year during solar cycle Fig. 5: Average number of storm days per year during solar cycle-24. The correlation between flares and GMS s has been observed good. It s clear from figure-4 and figure-5. Solar flare also a possible cause of GMSs. We categorized the flares according to intensity and determined possible relation with different type of flares. First take B-class flares, which show in figure-6. Total numbers of B-type flares are observed during the year 28 to 213, but weak correlation (r = ) has been found between B- type and GMS s. Then take C-class flares, which show in figure-7. Total numbers of C-type flares are during the study period but it is clear from figure correlation (r =.92) has been found between C-type and GMS is better than B type flare. Fig. 6: Average number of B-type Flares per year during solar cycle Fig. 7: Average number of C-type Flares per year during solar cycle-24 Then M-class flares have been taken, which shows in figure-8. Total numbers of M-type flares are 1352 but it is clear from figure-8 correlation (r =.94) has been found between M-type and GMS. Correlation is very good for M- type flare and it is better than B type flare. At last X-class flares has been taken, which shows in figure-9. Total numbers of X-type flares are very less its only 11in count. Correlation is very good (r =.88) for X- type flare and it is better than B type flare. It is observed that M and X-class flares are more geoeffective. (1)

5 X-type Flares M-type Flares Total 47 geomagnetic storms observed during the span of solar cycle 24 with Dst -5 nt. Using the minimum Dst value as an indicator, 36 moderate, 11 strong, none severe and great has been found during the cycle Similarly occurrences of Halo CMEs also do not follow the phase of solar cycle exactly, whereas yearly occurrence of GMSs follows the yearly occurrence of Halo CMEs. Consequently, halo CMEs are responsible for the occurrence of GMSs during the solar cycle The correlation between solar flares and GMS s has been observed good. It s clear from present study Solar flare also a possible cause of GMSs. Fig. 8: Average number of M-type Flares per year during solar cycle Fig. 9: Average number of X-type Flares per year during solar cycle-24 CONCLUSIONS r =.88 Based on the analysis done in this study, we summarize our important conclusions as given below: 1. Maximum phase of solar cycle-24 has been measured during the year 213, whereas the periods are the periods of minimum phase of solar activity. The current studies for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 98 in the ly occurrence of Geomagnetic storms does not follow the phase of solar cycle exactly during cycle It is observed that M and X-class flares may also be geoeffective during the cycle-24. REFERENCES Carrington R C, MNRAS 2 13 (186) Chapman S and V C A Ferraro Nature 129 (193) Gopalswamy, N. (211), ASI Conference Series, 2, 241. Jain, R., Joshi, V., Kayasth, S.L., Dave, H. and Deshpande, M., Solar X-ray Spectrometer (SOXS) mission-low Energy Payload-First results (26), J.Astrophys. Astron., 27, Jain, R., Malini, A. and Sharanma, R., X-ray emission from flares (28), J. Asrtrophys. Astr, 29, Rathore, B.S., Kaushik, S.C., Bhadoria, R.M., Parashar, K.K. and Gupta, D.C. (212), Indian Journal of Physics, 86 (7), 563. Rathore, B.S., Kaushik, S.C., Bhadoria, R.M., Parashar, K.K. and Gupta, D.C., (211), International Journal of Applied Physics and Mathematics, 1 (2), 149. Rathore, B.S., Kaushik, S.C., Bhadoria, R.M., Parashar, K.K. and Gupta, D.C., (212),Advanced Materials Research, , Rathore, B.S., Kaushik, S.C., Parashar, K.K. and Kapil, P. (211), Proc. ICRC, 32, 47. Shrivastava, P.K., Jaiswal, A.M. (29), Proc. ICRC, 31, 1. Balveer S Rathore, Lakshmi Narain College of Technology (LNCT), Bhopal (India), balveer_singhra@yahoo.co.in. Dinesh C Gupta, School of Studies in Physics, Jiwaji University, Gwalior (India). (11)

6 Rammohan S Bhadoria, Research Scholar, School of Studies in Physics, Jiwaji University, Gwalior (India). K K Parashar, Research Scholar, School of Studies in Physics, Jiwaji University, Gwalior (India). Neetu Sikarwar, Assistant Professor, Electronics Department, Institute of Engineering, Jiwaji University, Gwalior (India). (12)