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Determining a Complex Solar Radio Burst Type II on 2nd November 2014 Driven by a Hydra Solar Flare As A Blast Waves

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

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 47

87--93

EN

Recent data of a complex solar radio burst type II is analyzed and reviewed. The monitoring of solar radio burst was done by using the Compact Astronomical Low cost, Low frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) from BLEIN 7 meter dish telescope at ETH, Zurich in frequency range of 25 until 1000 MHz. During the inspection of the X-ray spectrum, we observed that the C3-category flare was caused by a filament of magnetism, which rose up and erupted between 0400 and 0600 UT. This occurred three hours before the signature of solar radio burst type II. There are some of the material in the filament fell back to the sun, causing a flash of X-rays where it hit the Sun surface. This is a Hydra Flare which occurred without sunspots. On the basis of these results, we suggest that a single shock in the leading edge of the CME could be the source of the multiple type II bursts and support the notion that the CME nose and the CME-streamer interaction are the two main mechanisms able to generate the bursts.

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Type II Solar Radio Burst with a Split and Herring − Bones During a Minimum Solar Activity

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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Vol. 13, iss. 2

104--111

EN

A preliminary correlation study of the herring − bone type II with a type III solar burst of has been made. On the basis of this study and in combination with the observation in radio emission, an interpretation of the mechanism of the occurrence of this event has been proposed. The type II solar radio burst with a split and herring bone is occurring at the same time from 36 MHz till 50 MHz. We have noted that an individual type III burst also can be observed at 13:23 UT from 45-50 MHz. During that day, a stream of solar wind from a coronal hole on the Sun has disturbing Earth's magnetosphere creating a minor geomagnetic storm, G1 on the NOAA scale of G1-G5. In this case, the solar flare is not very high, but CME is responsible to form a solar radio burst type II. Overall, based on seven days observation beginning from 25th March 2013, the solar activity is considered as very low. The highest solar flare can be observed within 7 days is only a class of B8 flare. There was no CMEs event that directed to the Earth is detected. The geomagnetic field activities are also at minimum level. Although the solar flare event is at a lower stage, it is still possible to form the solar radio burst type II which is associated with CME event. From the selected event, although theoretically solar radio burst type II is associated with CMEs, there is no compelling solar radio burst type II without a flare. The only difference is the dynamic structure and the intensity and speed of both phenomena (solar flares and CMEs) which depend on the active region. Nevertheless, understanding how energy is released in solar flares is one of the central questions in astrophysics. This solar radio burst type II formation is the first event that successfully detected by e-CALLISTO network in 2013.

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The Tendencies and Timeline of the Solar Burst Type II Fragmented

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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Vol. 12

84--102

EN

We report the timeline of the solar radio burst Type II that formed but fragmented at certain point based on the eruption of the solar flare on 13th November 2012 at 2:04:20 UT. The active region AR 1613 is one of the most active region in 2012. It is well known that the magnetic energy in the solar corona is explosively released before converted into the thermal and kinetic energy in solar flares. In this work, the Compound Astronomical Low-frequency, Low-cost Instrument for Spectroscopy Transportable Observatories (CALLIISTO) system is used in obtaining a dynamic spectrum of solar radio burst data. There are eight active regions and this is the indicator that the Sun is currently active. Most the active regions radiate a Beta radiation. The active regions 1610, 1611 and 1614 are currently the largest sunspots on the visible solar disk. There is an increasing chance for an isolated M-Class solar flare event. It is also expected that there will be a chance of an M flare, especially from AR 1614 and 1610. Although these two observations (radio and X-rays) seem to be dominant on the observational analysis, we could not directly confirmed that this is the only possibility, and we need to consider other processes to explain in detailed the injection, energy loss and the mechanism of the acceleration of the particles. In conclusion, the percentage of energy of solar flare becomes more dominant rather than the acceleration of particles through the Coronal Mass Ejections (CMEs) and that will be the main reason why does the harmonic structure of type II burst is not formed. This event is one fine example of tendencies solar radio burst type III, which makes the harmonic structure of solar radio burst type II fragmented.

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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

Hamidi Z. S.

International Letters of Chemistry, Physics and Astronomy

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2014

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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.

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

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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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.

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Investigation on a Broken Solar Burst Type II during High Activities in AR1613 on 13th November 2012

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

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 9

8--15

EN

The present article is an attempt to analyze the solar burst Type II observations based on solar flare and Coronal Mass Ejections (CMEs) events. We choose an intriguing type II radio burst with a velocity of 1193 kms-1 that occurred on 2012 November 13 at 2:04:20 UT. In this case, the study of solar radio burst type III is of paramount importance because of the fact that it helps to gain an insight of generation mechanisms of solar flare and Coronal Mass Ejections (CMEs) phenomena. Here, we have got a reasonably clear idea of the various forms under which the type III continuum emission may appear and potentially form a type II burst. However, in this case, the Type II solar burst only successfully forms a fundamental structure within the first few minute period, but broken suddenly before evolve a harmonic structure. This phenomenon is very interesting to be tackled and study. How the burst suddenly broken is still ongoing research seems the event is very rare and hard to be proved. There are a few questions that cause this unique situation which related to: (i) the intensity and duration of type III burst which also related to the classification of solar flare (ii) the probabilities CMEs to occur during that time and also the factor of the total amount of massive burst that exploded, Thus, we can conclude that the solar burst type III event still tells us an enigmatic characteristic from time to time due to the relationship of energetic particles and streams of particles with coronal magnetic fields and the pattern of Sun activity due to the 24th solar cycle. It might an interesting to study in detail the main factor that caused the Type II solar burst broken. Indirectly, it might because of the very intense of solar flares that make the percentage of energy of solar flare become more dominant rather than the acceleration of particles through the Coronal Mass Ejections. Thus, we realize that the potential energy during this event is higher than the kinetic energy of the particles.

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Fundamental and Second Harmonic Bands of Solar Radio Burst Type II Caused by X1.8 - Class Solar Flares

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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Vol. 14, iss. 2

208-217

EN

An extreme 2012 October 23 solar flare event marked on the onset of the CALLISTO data, being one of the highest solar flare event that successfully detected. The formation of harmonic solar burst type II in meter region and their associated with X1.8-class solar flares has been reported. This burst has been observed at the National Space Centre, Banting, detected by the Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) system in the range of 150-400 MHz in the low frequency band. It occurred between 3.17:45 UT to 3.19:00 UT within 1 minute 15 seconds. The Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory CALLISTO spectrometer is a solar dedicated spectrometer system that has been installed all over the world to monitor the Sun activity in 24 hours. The growth of this burst is often accompanied by abundance enhancement of particles which may take the form of multiple independent drifting bands or other forms of fine structure. Due to the results, the drift rate of this burst is 2.116 MHz s–1, which is considered as a slow drift rate. These drifting bands are approximately having a frequency ratio 2:1. This burst is a particular interest, though of sporadic and infrequent occurrence. The splitting is due to the effect of magnetic splitting, analogous to the Zeeman Effect. This is one of the examples which the type II burst is not always associated with CMEs event. The combination of radio and x-ray region give a complete view of the solar flare eruption from e active region AR1598. Both different electromagnetic spectrum shows the exact time. Other interesting results is that this type II burst is not associated with CMEs as usual, but due to the very high solar flare event with a fundamental form at more than 100 MHz. An extension of the present work will be a detailed study of the possible triggering and the driving mechanism of solar flare explosion.

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Characterization of Selected Solar Radio Bursts Based on Solar Activity Detected by e- CALLISTO (Malaysia)

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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Vol. 13, iss. 2

144--159

EN

One of the main reasons to study more about the dynamics of solar radio bursts is because solar these bursts can interfere with the Global Positioning System (GPS) and communications systems. More importantly, these bursts are a key to understand the space weather condition. Recent work on the interpretation of the low frequency region of a main solar burst is discussed. Continuum radio bursts are often related to the solar activities such as an indication of the formation of sunspot, impulsive phase of solar flares and Coronal Mass Ejections (CMEs) and their frequencies correspond to the densities supposed to exist in the primary energy release volume. Specifically, solar burst in low frequency play an important role in interpretation of Sun activities. In this work, we have selected few solar bursts that successfully detected by our station at the National Space Centre, Banting Selangor. Our objective is to correlate the solar burst with Sun activities by looking at the main sources that responsibility with the trigger of solar burst. It is found that type II burst is dominant with Coronal Mass Ejections (CMEs), type III burst associated with solar flare, IV burst with the formation of active region and type U burst high solar flare. We believed that this work is a good start to monitor Sun’s activities in Malaysia as equatorial country.

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Analysis of temperature dependence of dark current mechanisms in MWIR type-II superlattice photodiodes

Wróbel J., Madejczyk P., Gawron W., Rogalski A.

Elektronika : konstrukcje, technologie, zastosowania

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2013

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Vol. 54, nr 9

113-116

EN

We report on temperature dependence characteristics of mid wavelength InAs/GaSb type-II superlattice photodiodes in a temperature range from 120 K to 240 K. A bulk based model with an effective bandgap of superlattice material has been used in modelling of the experimental data. Temperature and bias dependent differential resistances have been analyzed in detail due to contributing mechanisms that limit the electrical performance of the diodes. C1-HH1 reduced mass was estimated from the fitting to the high reverse bias (< - 1.0 V) voltage, and given about 0.015 m0 in the whole considered temperature range. This value agree well with much more complex simulations and cyclotron resonance measurements. Obtaining so good results was possible thanks to including series resistance into calculations.

PL

W pracy przedstawiono analizę charakterystyk prądowo-napięciowych oraz rezystancji dynamicznych fotodiod PIN z supersieci II typu InAs10ML/ GaSb10ML zakresu średniej podczerwieni. Rozważania teoretyczne transportu nośników przeprowadzono stosując teorię Shockley’a złącza wykonanego w materiale objętościowym. W zakresie temperatur 120 - 240 K zaobserwowano kilka mechanizmów składowych prądu ciemnego, w tym: mechanizm dyfuzyjny i generacyjno-rekombinacyjny, dwa mechanizmy tunelowania, oraz upływność powierzchniową. W obliczeniach uwzględniono również wpływ rezystancji szeregowej, który szczególnie w zakresie temperatur osiąganych przez chłodziarki termoelektryczne (T > 180 K), okazał się znaczący. Wybrane parametry dopasowujące uzyskane z analitycznych zależności na składowe prądu ciemnego (w tym masę zredukowaną przejścia C1-HH1) zostały porównane z dostępnymi literaturowymi danymi eksperymentalnymi.