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1

An X-ray Observations of A Gradual Coronal Mass Ejections (CMEs) on 15th April 2012

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Hamidi Z. S. , Shariff N. N. M. , Monstein C. , Wan Zulkifli W. N. A. , Ibrahim M. B. , Arifin N. S. , Amran N. A.

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tom Vol. 8

13--19

EN

In the present work, we will highlight the solar observation during 15th April 2012, solar filament eruption which is accompanied by an intense and gradual Coronal Mass Ejections (CMEs) The explosion of CMEs was observed at 2:12:06 UT and also can be observed by the Solar Dynamics Observatory (SDO) with an Active Region AR1458 is crackling with C-class solar flares. The solar flare class B3 and C2 were observed beginning 2241 UT and 0142 UT. The event is considered as second largest CMEs been detected since five years. Although the solar activity within a few days is considered quite low and there are no proton events were observed at geosynchronous orbit., the is still an unexpected explosion of CMEs can be occurred. The radio flux number (10.7 cm) exceeds 102 with the number of sunspot and area of sunspot increased to 77 and 270. The velocity of CMEs was calculated based on the LASCO2 data. From the results, it is clearly seen that the range of the velocity is between 200 kms-1 to 2000 kms-1. This wide of range proved that the mechanism of the CMEs is a gradual process. The explosion of CMEs velocity is located from 80º - 255º from North of the Sun. We can then conclude that currently, the rearrangement of the magnetic field, and solar flares may result in the formation of a shock that accelerates particles ahead of the CMEs loop and an active region play an important character in this event.

2

The response of TEC at quasi-conjugate point GPS stations during solar flares

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Bahari S. A. , Abdullah M. , Yatim B.

Acta Geophysica

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2011

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tom Vol. 59, no. 2

407-427

EN

Global Positioning System (GPS) derived total electron content (TEC) measurements were analyzed to investigate the ionospheric response during the X-class solar flare event that occurred on 5-6 December 2006 at geomagnetic conjugate stations: Syowa, Antarctica (SYOG) (GC: 69.00° S, 39.58° E; CGM: 66.08° S, 71.65° E) and Árholt, Iceland (ARHO) (GC: 66.19° N, 342.89° E; CGM: 66.37° N, 71.48° E). Bernese GPS software was used to derive the TEC maps for both stations. The focus of this study is to determine the symmetry or asymmetry of TEC values which is an important parameter in the ionosphere at conjugate stations during these solar flare events. The results showed that during the first flares on 5 December, effects were more pronounced at SYOG than at ARHO. However, on 6 December, the TEC at ARHO showed a sudden spike during the flare with a different TEC variation at SYOG.

3

Enormous Eruption of 2.2 X-class Solar Flares on 10th June 2014

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Hamidi Z. S. , Shariff N. N. M.

International Letters of Chemistry, Physics and Astronomy

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2014

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tom Vol. 17, iss. 3

249--257

EN

The observational of active region emission of the Sun contain an critical answer of the time-dependence of the underlying heating mechanism. In this case, we investigate an X2.2 solar flare from a new Active Region AR2087 on the southeast limb of the Sun. The solar flare peaked in the X-rays is around 11:42 UT. It was found that the snapshot of this event from the Solar Dynamics Observatory (SDO) channel with the GOES X-ray plot overlayed. The flare is very bright causes by a diffraction pattern. We explore a parameter space of heating and coronal loop properties. Based on the wavelength, it shows plasma around 6 million Kelvin. At the same time, data from the NOAA issued an R3 level radio blackout, which is centered on Earth where the Sun is currently overhead at the North Africa region. This temporary blackout is caused by the heating of the upper atmosphere from the flare. The blackout level is now at an R1 and this will soon pass. Other than the temporary radio blackout for high frequencies centered over Africa this event will not have a direct impact on us. Until now, we await more data concerning a possible Coronal Mass Ejections (CMEs) but anything would more than likely not head directly towards Earth. An active region AR2087 just let out an X1.5 flare peaking at 12:52 UT. This shows plasmas with temperatures up to about 10 Million Kelvin. This event is considered one of the massive eruption of the Sun this year.

4

Chronology of Formation of Solar Radio Burst Types III and V Associated with Solar Flare Phenomenon on 19th September 2011

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Hamidi Z. S. , Shariff N. N. M.

International Letters of Chemistry, Physics and Astronomy

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2014

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tom Vol. 5

32--42

EN

The formation of two different solar bursts, type III and V in one solar flare event is presented. Both bursts are found on 19th September 2011 associated with C-class flares on active region 1295. From the observation, we believed that the mechanism of evolution the bursts play an important role in the event. It is found that type V burst appeared in five minutes after type III. There are a few active regions on the solar disk but most are magnetically simple and have remained rather quiet. An interpretation of this new result depends critically on the number of sunspots and the role of active region 1295. Sunspot number is increased up to 144 with seven sunspots can be observed. During that event, the speed of solar wind exceeds 433.8 km/second with 2.0 g/cm3 density of protons in the solar corona. Currently, radio flux is also high up to 150 SFU. The solar flare type C6 is continuously being observed in the X-ray region for 24 hours since 1541 UT and a maximum C1 is detected on 1847 UT. Although the sources of both bursts are same, the direction and ejection explode differ.

5

Radio Observation of Coronal Mass Ejections (CMEs) Due to Flare Related Phenomenon on 7th March 2012

88%

Hamidi Z. S. , Monstein C. , Shariff N. N. M.

International Letters of Chemistry, Physics and Astronomy

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2014

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tom Vol. 11, iss. 3

243--256

EN

On March 7th, 2012, an active region AR1429 has unleashed 2 major X-class solar flares. This flare is accompanied by a Coronal Mass Ejections (CMEs) event. A pair of unusually large solar flares early March 7, 2012 generated a Coronal Mass Ejection that was expected to reach Earth around midday March 8. In this case we focused on the second explosion of solar flare. It is found that the indication of signal potentially drives Coronal Mass Ejections (CMEs). There are a few types solar burst that can be observed, which is (i) an individual type III (ii) a complex type III (iii) subtype an H type II solar burst and (iv) type IV solar burst. The duration of solar burst is start from 1:02 UT to 2:00 UT. We also compare our results with the Geostationary Operational Environmental Satellites (GOES) data. Overall, one hour duration with a strong intensity burst are exploded strongly within the period. The fast drift type III burst has continued until 1:28 UT is associated with the large X 5.4 -class solar flares at 1:25:05 UT. It is undeniable that solar flare plays an important role in the Sun-Earth connection due to sudden changes of strong magnetic fields in the Sun’s corona. From our analysis, one possible reason behind the formation of this very complex, long duration of this loop is the magnetic reconnection and disruption of the loops which is observed during flare maximum. Until now, there has been an increasing interest in the space weather program has stimulated interest in this issue. A new experimental approach by e-CALLISTO with 24 hours monitoring and further development of a model of the theory are hoping to meet the current knowledge about the Sun behaviour.

6

Disturbances of Solar Eruption From Active Region AR1613

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Hamidi Z. S. , Shariff N. N. M. , Monstein C.

International Letters of Chemistry, Physics and Astronomy

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2014

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tom Vol. 13, iss. 1

77-87

EN

The paper describes an investigation of the solar radio bursts of spectral type III due to disturbances of the active region AR 1613. A solar flare occurred on 2012 November 15, between 2:00 UT to 3:30 UT. The sequence images from a burst from our site revealed that although the solar flare is considered moderate, it is still possible to obtain the solar burst type III in a single and group forms within one and half hour. It can easily produce misleading results in terms of non-thermal electron density and magnetic field strength. The burst is originated in the same active region of the solar corona. The C-6 level enhancement was detected in GOES 1.8 a soft X-ray. Based on the results, we suggest that radio wave source motion manifests the displacement of particle sites caused by plasma eruptions. Time variability in the emission may due to the changes in the electron density. The group and individual solar burst type III can be related to the distance travelled before an electron beam becomes unstable to Langmuir waves. In conclusion, the interactions non-thermal electron and magnetic trapping can influence the transporting of electrons and this is still a subject of interest of intense investigation.

7

Probability of Solar Flares Turn Out to Form a Coronal Mass Ejections Events Due to the Characterization of Solar Radio Burst Type II and III

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Hamidi Z. S.

International Letters of Chemistry, Physics and Astronomy

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2014

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tom Vol. 16

1--85

EN

The solar flare and Coronal Mass Ejections (CMEs) are well known as one of the most massive eruptions which potentially create major disturbances in the interplanetary medium and initiate severe magnetic storms when they collide with the Earth‟s magnetosphere. However, how far the solar flare can contribute to the formation of the CMEs is still not easy to be understood. These phenomena are associated with II and III burst it also divided by sub-type of burst depending on the physical characteristics and different mechanisms. In this work, we used a Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy in Transportable Observatories (CALLISTO) system. The aim of the present study is to reveal dynamical properties of solar burst type II and III due to several mechanisms. Most of the cases of both solar radio bursts can be found in the range less that 400 MHz. Based on solar flare monitoring within 24 hours, the CMEs that has the potential to explode will dominantly be a class of M1 solar flare. Overall, the tendencies of SRBT III burst form the solar radio burst type III at 187 MHz to 449 MHz. Based on solar observations, it is evident that the explosive, short time-scale energy release during flares and the long term, gradual energy release expressed by CMEs can be reasonably understood only if both processes are taken as common and probably not independent signatures of a destabilization of pre-existing coronal magnetic field structures. The configurations of several active regions can be sourced regions of CMEs formation. The study of the formation, acceleration and propagation of CMEs requires advanced and powerful observational tools in different spectral ranges as many „stages‟ as possible between the photosphere of the Sun and magnetosphere of the Sun and magnetosphere of the Earth. In conclusion, this range is a current regime of solar radio bursts during CMEs events.

8

The Evolution of Unstable 'Beta-Gamma' Magnetic Fields of Active Region AR 2222

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Hamidi Z. S. , Sabri S. N. U. , Shariff N. N. M. , Monstein C.

International Letters of Chemistry, Physics and Astronomy

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2015

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tom Vol. 48

95--102

EN

This event allows us to investigate how plasma–magnetic field interactions in the solar corona can produce suprathermal electron populations over periods from tens of minutes to several hours, and the interactions of wave-particle and wave-wave lead to characteristic fine structures of the emission. An intense and broad solar radio burst type IV was recorded by CALLISTO spectrometer from 240360 MHz. Using data from a the KRIM observatory, we aim to provide a comprehensive description of the synopsis formation and dynamics of a a single solar burst type IV event due to active region AR2222. For five minutes, the event exhibited strong pulsations on various time scales and “broad patterns” with a formation of a group type III solar burst. AR 2222 remained the most active region, producing a number of minor C-Class solar flares. The speed of the solar wind also exceeds 370.8 km/second with 10.2 g/cm3 density of proton in the solar corona. The radio flux also shows 171 SFU. Besides, there are 3 active regions, AR2217, AR2219 and AR2222 potentially pose a threat for Mclass solar flares. Active region AR2222 have unstable 'beta-gamma' magnetic fields that harbor energy for M-class flares. As a conclusion, we believed that Sun’s activities more active in order to achieve solar maximum cycle at the end of 2014.

9

An Analysis of Solar Burst Type II, III, and IV and Determination of a Drift Rate of a Single Type III Solar Burst

75%

Hamidi Z. S. , Ibrahim M. B. , Shariff N. N. M. , Monstein C.

International Letters of Chemistry, Physics and Astronomy

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2014

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tom Vol. 19, iss. 2

160--170

EN

The main feature of solar radio type II, III and IV burst is outlined. In this event there are three combinations of bursts that related to the solar flare phenomenon on 6th July 2012. This event is one of good example to observe how far the influence of type II burst could impact the formation of type IV burst and III solar bursts. At first stage, it was observed that a sub-type of H burst form within 2 minutes before type IV solar burst form. The type IV burst is due to the eruption of active region AR 1515 with a fine structure (FS). We used a Blein CALLISTO data in this case. Further analysis also showed that the total energy of the burst are in the range of 4.875 × 10-25 J to 8.48 × 10-25 J and plasma frequency is equal to 1.24 × 104 Hz. Therefore, we could say that in this case, before the solar burst type III occurred, the ejection of CMEs already ejected.

10

Occurrences Rate of Type II and III Solar Radio Bursts at Low Frequency Radio Region 45 − 870 MHz

63%

Hamidi Z. S. , Shariff N. N. M. , Monstein C.

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tom Vol. 18

103--112

EN

Observations of type II and III solar bursts indicate that while type III bursts may appear at any altitude, from the very low corona into interplanetary space, type II solar bursts do not act the same way. This work focuses on recent observations in the radio region on the low frequency region from 45 MHz to 870 MHz. Our analysis employed the accuracy of the daily solar burst measurements of e-CALLISTO network. It was found that solar burst type II explode quite minimum with 1-2 events from 2006 - 2010. However, the data 2011 for solar burst type II increases drastically with 16 events has been recorded. The occurrences of Coronal Mass Ejections (CMEs) events are also increasing up to four times in 2011. Most of the both events can be observed in the range of 150 MHz till 500 MHz. Overall, we can say that the range of photon energy for solar burst type III is between 7.737 x 10-7 eV to 1.569 x 10-6 eV. In the case of solar burst type II, the distribution of energy is much smaller with 1.596 x 10-6 eV to 6.906 x 10-6 eV. Detailed investigation of solar burst will concern the 2011 data seem to show a significant trend for both types. We showed that the increasing of both solar burst events via years implies directing an increasing of solar activities including sunspot number, solar flare and Coronal Mass Ejections (CMEs) events. It is expected that both types will increase gradually in the beginning of 2014.

11

A Case Study of Explosion A Single Solar Burst Type III and IV Due to Active Region AR1890

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Hamidi Z. S. , Ibrahim M. B. , Shariff N. N. M. , Monstein C.

International Letters of Chemistry, Physics and Astronomy

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2014

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tom Vol. 19, iss. 2

171--180

EN

Using data from a BLEIN Callisto site, we aim to provide a comprehensive description of the synopsis formation and dynamics of a a single solar burst type III and IV event due to active region AR1890. This eruption has started since 14:15 UT with a formation of type III solar burst. To investigate the importance of the role of type III solar burst can potentially form a type IV solar burst, the literature review of both bursts is outlined in detailed. The orientation and position of AR1890 make the explosion of a class C-solar flare is not directly to the Earth. Nevertheless, it is clear that the interactions of others sunspots such as AR1893,AR1895,AR1896, AR1897 and AR1898 should be studied in detail to understand what makes the type III burst formed before the type IV solar burst.

12

Kosmiczna pogoda

44%

Stanislawska I.

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2005

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nr 3

4-7