The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Dale E. Gary - One of the best experts on this subject based on the ideXlab platform.
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Solar Radio Burst effects on wireless systems
2011 IEEE International Symposium on Electromagnetic Compatibility, 2011Co-Authors: Dale E. GaryAbstract:The Sun is capable of producing strong Radio emission during times of flaring activity that can directly affect wireless communication and navigation systems without warning. We give some examples of specific effects that have been documented, including increased dropped-call levels on cellular telephone systems and system-wide interference on the Global Positioning System (GPS). To assess the potential and degree of risk presented by Radio outBursts from the Sun, we survey what is known about the frequency of occurrence of Solar Bursts as a function of frequency and time. We show that a firm assessment of risk remains unknown due to lack of complete coverage in the monitoring of Solar Bursts, but we present some expectations based on current knowledge. We conclude that effects on wireless systems in space are likely to occur, but can be mitigated by considering and accounting for Solar Burst properties.
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the korean Solar Radio Burst locator ksrbl
Publications of the Astronomical Society of the Pacific, 2009Co-Authors: Dale E. Gary, Su-chan Bong, Kyung-suk Cho, Young-deuk Park, Yujiang Dou, Zhiwei Liu, Gelu M Nita, Yong-jae MoonAbstract:This paper describes the design and operation of the Korean Solar Radio Burst Locator (KSRBL). The KSRBL is a Radio spectrometer designed to observe Solar decimeter and microwave Bursts over a wide band (0.245-18 GHz) as well as to detect the Burst locations without interferometry or mechanical sweeping. As a prototype, it is temporarily observing at the Owens Valley Radio Observatory (OVRO), California, USA, and after commissioning will be operated at the Korea Astronomy and Space Science Institute (KASI), Daejeon, Republic of Korea. The control system can agilely choose four 500 MHz intermediate frequency (IF) bands (2 GHz instantaneous bandwidth) from the entire 0.245-18 GHz band, with a standard time resolution of 100 ms, although higher time resolution is possible subject to data-rate constraints. To cover the entire band requires 10 tunings, which are therefore completed in 1 s. Each 500 MHz band is sampled at a 1 GS s-1 (gigasample per second) rate, and 4096 time samples are Fast Fourier transformed (FFT) to 2048 subchannels for a frequency resolution of 0.24 MHz. To cover the entire range also requires two different feeds, a dual-frequency Yagi centered at 245 and 410 MHz, and a broadband spiral feed covering 0.5-18 GHz. The dynamic range is 35 dB over the 0.5-18 GHz band, and 55 dB in the 245 and 410 MHz bands, set by using switchable attenuators in steps of 5 dB. Each 500 MHz IF has a further 63 dB of settable analog attenuation. The characteristics of the spiral feed provide the ability to locate flaring sources on the Sun to typically 2'. The KSRBL will provide a broadband view of Solar Bursts for the purposes of studying Solar activity for basic research, and for monitoring Solar activity as the source of Space Weather and Solar-terrestrial effects.
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Global Positioning System and Solar Radio Burst forensics
Radio Science, 2009Co-Authors: Dale E. Gary, Brady W. O'hanlon, Paul M. KintnerAbstract:[1] On 6 December 2006, a Solar Radio Burst associated with a class X6 Solar flare demonstrated that GPS receiver operation is vulnerable to Solar Radio Burst noise at 1.2 GHz and 1.6 GHz. Within 8 days, two more Solar Radio Bursts confirmed the initial results. These Solar Radio Bursts occurred at Solar minimum when they were least expected. Given that measurements of Solar Radio Bursts extend back to at least 1960, why did 40 years pass before anyone realized that Solar Radio Bursts could be so intense or pose a potential threat to the continuous availability of GPS operations? An investigation has been conducted to see if archived Solar Radio Burst data or GPS data could be used to detect intense Solar Radio Bursts. With the exception of the intense Solar Radio Bursts of December 2006, we find that when both GPS data and Radio Solar Telescope Network (RSTN) data are available, they agree within the limits presented by differing reception frequencies and unknown polarization. However, inconsistencies and lapses within the RSTN data set were also discovered, making it unlikely that we will ever know the true number of intense (>150,000 Solar flux unit) Solar Radio Bursts that may have occurred during the last 40 years.
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effect of intense december 2006 Solar Radio Bursts on gps receivers
Social Work, 2008Co-Authors: Alessandro P. Cerruti, Dale E. Gary, P M Kintner, A J Mannucci, Robert F Meyer, Patricia H Doherty, A J CosterAbstract:[1] Solar Radio Bursts during December 2006 were sufficiently intense to be measurable with GPS receivers. The strongest event occurred on 6 December 2006 and affected the operation of many GPS receivers. This event exceeded 1,000,000 Solar flux unit and was about 10 times larger than any previously reported event. The strength of the event was especially surprising since the Solar Radio Bursts occurred near Solar minimum. The strongest periods of Solar Radio Burst activity lasted a few minutes to a few tens of minutes and, in some cases, exhibited large intensity differences between L1 (1575.42 MHz) and L2 (1227.60 MHz). Civilian dual frequency GPS receivers were the most severely affected, and these events suggest that continuous, precise positioning services should account for Solar Radio Bursts in their operational plans. This investigation raises the possibility of even more intense Solar Radio Bursts during the next Solar maximum that will significantly impact the operation of GPS receivers.
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Transition radiation in turbulent astrophysical medium. Application to Solar Radio Bursts
arXiv: Astrophysics, 2007Co-Authors: Gregory D Fleishman, Dale E. Gary, Gelu M NitaAbstract:Modern observations and models of various astrophysical objects suggest that many of their physical parameters fluctuate substantially at different spatial scales. The rich variety of the emission processes, including Transition Radiation but not limited to it, arising in such turbulent media constitutes the scope of Stochastic Theory of Radiation. We review general approaches applied in the stochastic theory of radiation and specific methods used to calculate the transition radiation produced by fast particles in the magnetized randomly inhomogeneous plasma. The importance of the theory of transition radiation for astrophysics is illustrated by one example of its detailed application to a Solar Radio Burst, including specially designed algorithms of the spectral forward fitting.
Christian Monstein - One of the best experts on this subject based on the ideXlab platform.
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Investigation into CME Shock Speed Resulting from Type II Solar Radio Bursts: A Newly Designed Half-Wave Dipole Antenna (HWDA) Array System
Solar Physics, 2020Co-Authors: F.a.m. Pauzi, Zamri Zainal Abidin, S.j. Guo, Guan-nan Gao, L. Dong, Christian MonsteinAbstract:An investigation into Type II Solar Radio Bursts was carried out to understand the frequency gap between fundamental and harmonic emissions of the Radio Burst. This investigation focused on Type II Solar Radio Bursts with flares and coronal mass ejections by relating the separation between fundamental and harmonic emissions. We used the Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Spectrometers (CALLISTO) and a newly designed low-frequency antenna array. This article describes the proposed new instrument in terms of its antenna design, the bandpass testing of the antenna, the new system significance in studying Type II Solar Radio Bursts, and its comparison with other leading Radio Solar monitoring instruments. Upon setting up the new technology, the Radio-frequency interference of the observation site at the University of Malaya was shown to emphasize the suitability of the selected site. This article also shows the preliminary results of the proposed new instrument by reporting the detection of a Type III Solar Radio Burst that was confirmed by CALLISTO. Moreover, it also includes the optimal observation design and strategies for future detections.
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Geomagnetic storm related to intense Solar Radio Burst type II and III due to M3.9 class flare and coronal mass ejections
Journal of Fundamental and Applied Sciences, 2018Co-Authors: Nurul Hazwani Husien, N. H. Zainol, N. N. M. Shariff, Christian Monstein, M. O. Ali, S. N. U. Sabri, Z. S. Hamidi, W. Z. A. Wan Mokhtar, M. S. FaidAbstract:The strong energetic particles ejected during sun’s activity will propagate towards earth and contribute to Solar Radio Bursts. These Solar Radio Bursts can be detected using CALLISTO system. The open website of the NASA provides us the data including CALLISTO, TESIS, Solar monitor, SOHO and space weather. The type III and II Solar Radio Burst on 9th November 2015 due to M3.9 class Solar flare and coronal mass ejections event has expected to cause the geomagnetic storm on 11th November 2015. The geomagnetic storm reached the Earth a day earlier than expected date due to high speed coronal mass ejections that more than 950 km/s and high energy of ejected particle that causes the M3.9 class flare and coronal mass ejections. The geomagnetic storm luckily does not give high impact on earth because the event on sun, which triggered this storm not heading toward earth.Keywords: Solar Radio Burst; coronal mass ejections; geomagnetic storm; Solar flare
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Implementation of Frequency Drift for Identification of Solar Radio Burst Type II
International Journal on Advanced Science Engineering and Information Technology, 2016Co-Authors: Nur Zulaikha Mohd Afandi, Roslan Umar, Zamri Zainal Abidin, Nor Hazmin Sabri, Zainol Abidin Ibrahim, Christian MonsteinAbstract:Sun is constantly produced mass and radiation during its natural activities, which will interact with ionosphere and affect the earth weather. In Radio astronomer community, CALLISTO is used to capture the Radio signal comes from Solar activities such as Solar Burst. Solar flares and Coronal Mass Ejections (CMEs) were closely associated with the production of Solar Radio Burst Type II and III. However, the determination of Solar Burst existence is done manually using spectrograph which appears for every 15 minutes. In order to assist the Solar Radio researcher to speed up the process of Solar Burst identification and detection, this work presents a new algorithm to auto classify Solar Radio Burst Type II and III. The value of frequency drift was used as the main idea in this auto classify algorithm because it can easily implemented using MATLAB. There are three main steps involved named as pre-processing, identification and classification. Auto calculation of frequency drift Burst on spectra was obtained from two parts which are frequency axis (df) and time axis (dt). The results of the frequency drift implementation in classification algorithm show that the algorithm developed gave almost similar determination as in manual detection. However, there are always have rooms for improvement for better detection system in future which may include specific characterization of Bursts and improved noise elimination.
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Effective Data Collection and Analysis of Solar Radio Burst Type II Event Using Automated CALLISTO Network System
2016 International Conference on Industrial Engineering Management Science and Application (ICIMSA), 2016Co-Authors: N. H. Zainol, N. N. M. Shariff, Christian Monstein, S. N. U. Sabri, Z. S. Hamidi, Nurul Hazwani Husien, M. S. FaidAbstract:The Callisto network systems are widely used for continuous data collection of Solar activities every day through the internet connection and stored in the central database in the computer. The system installation began in 2002 in Zurich, and its network has spread all around the globe ever since, benefiting researchers and individuals worldwide. This research paper presents one of selected event using a Radio spectrometer the Callisto system from Ireland, which demonstrates a Solar Radio Burst event detected during the 13:23 (UT) to 13:26 (UT) on 30th March 2013 in Ireland. Besides, data from Glasgow and Humain were compared to be analyzed. Those installed Callisto in each country is called as extendable the Callisto system (e-Callisto). The analysis being carried out based on spectrogram data of the CALLISTO system obtained from these three countries. Results showed that all three sites observed the same Solar Radio Burst Type II at the same time but different in locations. The e- CALLISTO system has proven to be a new tool for monitoring Solar activity and for space weather research.
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the dependence of log periodic dipole antenna lpda and e callisto software to determine the type of Solar Radio Burst i v
International Conference on Industrial Engineering Management Science and Application, 2016Co-Authors: S. N. U. Sabri, Zety Sharizat Hamidi, N. N. M. Shariff, M. O. Ali, M. S. Faid, N H Zainol, Nurulhazwani Hussien, Christian MonsteinAbstract:Solar Radio Burst originated at the layer of the atmosphere where the Geo-effective disturbance occurred which energy will be released in Solar flares and Coronal Mass Ejections (CMEs) will be launched. Solar Radio Burst can be divided into 5 types and determined by using the Log Periodic Dipole Antenna (LPDA) and e-CALLISTO system. The LPDA was set up in a 45-870 MHz range in frequency and has maximum boom length 5.45m. Besides that, it has minimum scale factor, τ=0.76 and maximum at τ=0.98. We put some effort to construct suitable with designs, high specification and practical enough with the size of boom length as the conclusion the scale factor that suitable with this design is 0.8118 as a directivity of an antenna. LPDA has 19 elements which using two (2) aluminium rod with 7.01dB gain. The antenna has a function to receive the signals then connected to the low noise amplifier and e-CALLISTO spectrometer completes it as a system. A CALLISTO (Compound Astronomical Low-Cost- Low-Frequency Instrument for Spectroscopy Transportable Observatory) spectrometer was used to figure out the dynamic of Solar corona which in metric and decimetric wavelength Radio observation and the main objective of this study was to study how the Solar Radio Burst can be detected by using LPDA (Malaysia) and e-CALLISTO (ETH Zurich, Switzerland) which were set up in a different location.In this paper, the potential of Malaysia be one of the candidates to contribute a good data will be highlighted and we will focus more on performance evaluation and visualization data.
Zety Sharizat Hamidi - One of the best experts on this subject based on the ideXlab platform.
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signal detection of the Solar Radio Burst type iii based on the callisto system project management
International Conference on Industrial Engineering Management Science and Application, 2016Co-Authors: Zety Sharizat Hamidi, N. N. M. Shariff, M. O. Ali, S. N. U. Sabri, Nurul Hazwani Husien, M. S. Faid, N H Zainol, Christian MonsteinAbstract:The E-CALLISTO (Compact Astronomical Low Cost Frequency Instrument for Spectroscopy and Transportable Observatory) network is a worldwide system in order to observe the Sun's activity in the Radio region. At present, more than 80 instruments have been installed at more than 43 locations, with users from more than 113 countries in the e- CALLISTO network. At present, more than 80 instruments have been installed at more than 43 locations, with users from more than 113 countries in the e-CALLISTO network. In this paper, we make use of the e-CALLISTO data that shows a sign of Solar activity. On 9th May, the Solar Radio Burst Type III (SRBT III) happens for two times. The first detection of SRBT III occurred less than 1 minute within 05:31UT and 05:32 UT as illustrated in Figure 3. The second SRBT III seems to be occurred within 05:41 UT to 05:42 UT for approximately 1 minute. The Coronal mass ejection which was ejected from the active region AR2339, was detected at 05:42UT has the 'beta-gamma' magnetic field that harbors energy for strong Solar flares. From the results, the point we wish to make here is that at least some of these type III Bursts with low starting frequencies are consistent with front-side flares, which indicates to us that the low starting frequencies observed for many of these Bursts are intrinsic to the type III emissions and do not result from occulting of the high-frequency emissions from any plasma structures.
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e callisto network system and the observation of structure of Solar Radio Burst type iii
International Conference on Industrial Engineering Management Science and Application, 2016Co-Authors: M. O. Ali, Zety Sharizat Hamidi, N. N. M. Shariff, S. N. U. Sabri, Nurul Hazwani Husien, M. S. Faid, N H Zainol, Christian MonsteinAbstract:Abstract- This paper highlighted on the unique occurrence of the Solar Radio Burst Type III (SRBT III) during the high activities of the Sun. e- CALLISTO network is the system that responsible for the observation of the Sun 24 hours per day, which is a program under IHY/UNBSSI and ISWI instrument deployment program. The data was taken from one of the part of e-CALLISTO network which is Bleien, Switzerland. The event that had been selected was on 27th August 2015 since there was two subtypes of SRBT III can be obviously observed during the day within 12:00 UT till 12:05 UT. The current condition of Solar wind speed is 348 km/s with density 8.4 protons/cm3. Besides the magnetic flux also quite high which is 13.4 nT. Regarding the detection of SRBT III, the x-ray flux data from Solar Monitor shows there is strong class m- flare also occur. The strong flare is also believed to have high temperature due to the high magnetic field. A geo-effective explosion was occur even though the sunspot no longer directly facing on the earth. The active region AR2403 was predicted can potentially cause Radio blackout and radiation storm as long as the sunspot remains visible.
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the dependence of log periodic dipole antenna lpda and e callisto software to determine the type of Solar Radio Burst i v
International Conference on Industrial Engineering Management Science and Application, 2016Co-Authors: S. N. U. Sabri, Zety Sharizat Hamidi, N. N. M. Shariff, M. O. Ali, M. S. Faid, N H Zainol, Nurulhazwani Hussien, Christian MonsteinAbstract:Solar Radio Burst originated at the layer of the atmosphere where the Geo-effective disturbance occurred which energy will be released in Solar flares and Coronal Mass Ejections (CMEs) will be launched. Solar Radio Burst can be divided into 5 types and determined by using the Log Periodic Dipole Antenna (LPDA) and e-CALLISTO system. The LPDA was set up in a 45-870 MHz range in frequency and has maximum boom length 5.45m. Besides that, it has minimum scale factor, τ=0.76 and maximum at τ=0.98. We put some effort to construct suitable with designs, high specification and practical enough with the size of boom length as the conclusion the scale factor that suitable with this design is 0.8118 as a directivity of an antenna. LPDA has 19 elements which using two (2) aluminium rod with 7.01dB gain. The antenna has a function to receive the signals then connected to the low noise amplifier and e-CALLISTO spectrometer completes it as a system. A CALLISTO (Compound Astronomical Low-Cost- Low-Frequency Instrument for Spectroscopy Transportable Observatory) spectrometer was used to figure out the dynamic of Solar corona which in metric and decimetric wavelength Radio observation and the main objective of this study was to study how the Solar Radio Burst can be detected by using LPDA (Malaysia) and e-CALLISTO (ETH Zurich, Switzerland) which were set up in a different location.In this paper, the potential of Malaysia be one of the candidates to contribute a good data will be highlighted and we will focus more on performance evaluation and visualization data.
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an automated system for signal detection of Solar Radio Burst type ii due to coronal mass ejections phenomena
International Conference on Information Science and Applications, 2016Co-Authors: N. H. Zainol, Zety Sharizat Hamidi, N. N. M. Shariff, Christian MonsteinAbstract:This paper presents the signal detection by automated system for an event related to Solar phenomena. Here, a system of Compound Astronomical Low-Cost Low-Frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) for detecting, interpreting and observing automatically Radio signal obtained from Solar activity is been used. The system observes and collects Radio signal for every day via internet and stored in a central data and it is a worldwide network of Radio spectrometer where has been installed in various locations all over the world. An event detects by the CALLISTO on 2nd November 2014 in Blein, Switzerland shows the present of Solar Radio Burst type II due to Coronal Mass Ejections (CMEs). The Log Periodic Dipole Antenna (LPDA) was connected to the CALLISTO system software to collect the signal of Solar activity. LPDA monitors Solar Radio flux in due to Solar Radio Burst type II phenomena. It standardized the frequency range for CALLISTO networking to operate well. CALLISTO system has already proven to be a precious new tool for monitoring Solar activity and for space weather research.
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the international cooperation of Solar Radio Burst project using e callisto system network
International Conference on Information Science and Applications, 2016Co-Authors: Zety Sharizat Hamidi, N. N. M. Shariff, C Monstein, Abdel Baset Mohamed El Nabwi Abdel Hamid Ibrahim, M I M YusofAbstract:The CALLISTO (Compound Low Cost-Low Frequency for Transportable Observatories) system is one of the most outstanding project under ISWI with there are more than 80 instruments in more than 43 locations with users from more than 116 countries. In this paper, we will highlight the concept of CALLISTO, distributing the observational sites all over the world and how this system is become as one of the efficient solutions to achieve the 24 hours Radio observation. This innovative project is to monitor the Sun at the Radio frequency range, which is very important to understand the Solar flare and Coronal Mass Ejections correspond to different aspects of the same magnetic energy release. Malaysia also occupies an important role in the CALLISTO due to the 12 hours monitoring of Solar activities throughout the year. Since 2007, the e-CALLISTO system has already proven to be a valuable new tool for monitoring Solar activity and for space weather research.
N. N. M. Shariff - One of the best experts on this subject based on the ideXlab platform.
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Geomagnetic storm related to intense Solar Radio Burst type II and III due to M3.9 class flare and coronal mass ejections
Journal of Fundamental and Applied Sciences, 2018Co-Authors: Nurul Hazwani Husien, N. H. Zainol, N. N. M. Shariff, Christian Monstein, M. O. Ali, S. N. U. Sabri, Z. S. Hamidi, W. Z. A. Wan Mokhtar, M. S. FaidAbstract:The strong energetic particles ejected during sun’s activity will propagate towards earth and contribute to Solar Radio Bursts. These Solar Radio Bursts can be detected using CALLISTO system. The open website of the NASA provides us the data including CALLISTO, TESIS, Solar monitor, SOHO and space weather. The type III and II Solar Radio Burst on 9th November 2015 due to M3.9 class Solar flare and coronal mass ejections event has expected to cause the geomagnetic storm on 11th November 2015. The geomagnetic storm reached the Earth a day earlier than expected date due to high speed coronal mass ejections that more than 950 km/s and high energy of ejected particle that causes the M3.9 class flare and coronal mass ejections. The geomagnetic storm luckily does not give high impact on earth because the event on sun, which triggered this storm not heading toward earth.Keywords: Solar Radio Burst; coronal mass ejections; geomagnetic storm; Solar flare
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Effective Data Collection and Analysis of Solar Radio Burst Type II Event Using Automated CALLISTO Network System
2016 International Conference on Industrial Engineering Management Science and Application (ICIMSA), 2016Co-Authors: N. H. Zainol, N. N. M. Shariff, Christian Monstein, S. N. U. Sabri, Z. S. Hamidi, Nurul Hazwani Husien, M. S. FaidAbstract:The Callisto network systems are widely used for continuous data collection of Solar activities every day through the internet connection and stored in the central database in the computer. The system installation began in 2002 in Zurich, and its network has spread all around the globe ever since, benefiting researchers and individuals worldwide. This research paper presents one of selected event using a Radio spectrometer the Callisto system from Ireland, which demonstrates a Solar Radio Burst event detected during the 13:23 (UT) to 13:26 (UT) on 30th March 2013 in Ireland. Besides, data from Glasgow and Humain were compared to be analyzed. Those installed Callisto in each country is called as extendable the Callisto system (e-Callisto). The analysis being carried out based on spectrogram data of the CALLISTO system obtained from these three countries. Results showed that all three sites observed the same Solar Radio Burst Type II at the same time but different in locations. The e- CALLISTO system has proven to be a new tool for monitoring Solar activity and for space weather research.
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e callisto network system and the observation of structure of Solar Radio Burst type iii
International Conference on Industrial Engineering Management Science and Application, 2016Co-Authors: M. O. Ali, Zety Sharizat Hamidi, N. N. M. Shariff, S. N. U. Sabri, Nurul Hazwani Husien, M. S. Faid, N H Zainol, Christian MonsteinAbstract:Abstract- This paper highlighted on the unique occurrence of the Solar Radio Burst Type III (SRBT III) during the high activities of the Sun. e- CALLISTO network is the system that responsible for the observation of the Sun 24 hours per day, which is a program under IHY/UNBSSI and ISWI instrument deployment program. The data was taken from one of the part of e-CALLISTO network which is Bleien, Switzerland. The event that had been selected was on 27th August 2015 since there was two subtypes of SRBT III can be obviously observed during the day within 12:00 UT till 12:05 UT. The current condition of Solar wind speed is 348 km/s with density 8.4 protons/cm3. Besides the magnetic flux also quite high which is 13.4 nT. Regarding the detection of SRBT III, the x-ray flux data from Solar Monitor shows there is strong class m- flare also occur. The strong flare is also believed to have high temperature due to the high magnetic field. A geo-effective explosion was occur even though the sunspot no longer directly facing on the earth. The active region AR2403 was predicted can potentially cause Radio blackout and radiation storm as long as the sunspot remains visible.
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signal detection of the Solar Radio Burst type iii based on the callisto system project management
International Conference on Industrial Engineering Management Science and Application, 2016Co-Authors: Zety Sharizat Hamidi, N. N. M. Shariff, M. O. Ali, S. N. U. Sabri, Nurul Hazwani Husien, M. S. Faid, N H Zainol, Christian MonsteinAbstract:The E-CALLISTO (Compact Astronomical Low Cost Frequency Instrument for Spectroscopy and Transportable Observatory) network is a worldwide system in order to observe the Sun's activity in the Radio region. At present, more than 80 instruments have been installed at more than 43 locations, with users from more than 113 countries in the e- CALLISTO network. At present, more than 80 instruments have been installed at more than 43 locations, with users from more than 113 countries in the e-CALLISTO network. In this paper, we make use of the e-CALLISTO data that shows a sign of Solar activity. On 9th May, the Solar Radio Burst Type III (SRBT III) happens for two times. The first detection of SRBT III occurred less than 1 minute within 05:31UT and 05:32 UT as illustrated in Figure 3. The second SRBT III seems to be occurred within 05:41 UT to 05:42 UT for approximately 1 minute. The Coronal mass ejection which was ejected from the active region AR2339, was detected at 05:42UT has the 'beta-gamma' magnetic field that harbors energy for strong Solar flares. From the results, the point we wish to make here is that at least some of these type III Bursts with low starting frequencies are consistent with front-side flares, which indicates to us that the low starting frequencies observed for many of these Bursts are intrinsic to the type III emissions and do not result from occulting of the high-frequency emissions from any plasma structures.
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the dependence of log periodic dipole antenna lpda and e callisto software to determine the type of Solar Radio Burst i v
International Conference on Industrial Engineering Management Science and Application, 2016Co-Authors: S. N. U. Sabri, Zety Sharizat Hamidi, N. N. M. Shariff, M. O. Ali, M. S. Faid, N H Zainol, Nurulhazwani Hussien, Christian MonsteinAbstract:Solar Radio Burst originated at the layer of the atmosphere where the Geo-effective disturbance occurred which energy will be released in Solar flares and Coronal Mass Ejections (CMEs) will be launched. Solar Radio Burst can be divided into 5 types and determined by using the Log Periodic Dipole Antenna (LPDA) and e-CALLISTO system. The LPDA was set up in a 45-870 MHz range in frequency and has maximum boom length 5.45m. Besides that, it has minimum scale factor, τ=0.76 and maximum at τ=0.98. We put some effort to construct suitable with designs, high specification and practical enough with the size of boom length as the conclusion the scale factor that suitable with this design is 0.8118 as a directivity of an antenna. LPDA has 19 elements which using two (2) aluminium rod with 7.01dB gain. The antenna has a function to receive the signals then connected to the low noise amplifier and e-CALLISTO spectrometer completes it as a system. A CALLISTO (Compound Astronomical Low-Cost- Low-Frequency Instrument for Spectroscopy Transportable Observatory) spectrometer was used to figure out the dynamic of Solar corona which in metric and decimetric wavelength Radio observation and the main objective of this study was to study how the Solar Radio Burst can be detected by using LPDA (Malaysia) and e-CALLISTO (ETH Zurich, Switzerland) which were set up in a different location.In this paper, the potential of Malaysia be one of the candidates to contribute a good data will be highlighted and we will focus more on performance evaluation and visualization data.
Eduard P Kontar - One of the best experts on this subject based on the ideXlab platform.
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first observation of a type ii Solar Radio Burst transitioning between a stationary and drifting state
The Astrophysical Journal, 2020Co-Authors: Nicolina Chrysaphi, Hamish A S Reid, Eduard P KontarAbstract:Standing shocks are believed to be responsible for stationary Type II Solar Radio Bursts, whereas drifting Type II Bursts are excited by moving shocks often related to coronal mass ejections (CMEs). Observations of either stationary or drifting Type II Bursts are common, but a transition between the two states has not yet been reported. Here, we present a Type II Burst which shows a clear, continuous transition from a stationary to a drifting state, the first observation of its kind. Moreover, band splitting is observed in the stationary parts of the Burst, as well as intriguing negative and positive frequency-drift fine structures within the stationary emissions. The relation of the Radio emissions to an observed jet and a narrow CME were investigated across multiple wavelengths, and the mechanisms leading to the transitioning Type II Burst were determined. We find that a jet eruption generates a streamer-puff CME and that the interplay between the CME-driven shock and the streamer is likely to be responsible for the observed Radio emissions.
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first observation of a type ii Solar Radio Burst transitioning between a stationary and drifting state
arXiv: Solar and Stellar Astrophysics, 2020Co-Authors: Nicolina Chrysaphi, Hamish A S Reid, Eduard P KontarAbstract:Standing shocks are believed to be responsible for stationary Type II Solar Radio Bursts, whereas drifting Type II Bursts are excited by moving shocks often related to coronal mass ejections (CMEs). Observations of either stationary or drifting Type II Bursts are common, but a transition between the two states has not yet been reported. Here, we present a Type II Burst which shows a clear, continuous transition from a stationary to a drifting state, the first observation of its kind. Moreover, band splitting is observed in the stationary parts of the Burst, as well as intriguing negative and positive frequency-drift fine structures within the stationary emissions. The relation of the Radio emissions to an observed jet and a narrow CME was investigated across multiple wavelengths, and the mechanisms leading to the transitioning Type II Burst were determined. We find that a jet eruption generates a streamer-puff CME and that the interplay between the CME-driven shock and the streamer is likely to be responsible for the observed Radio emissions.
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cme driven shock and type ii Solar Radio Burst band splitting
arXiv: Solar and Stellar Astrophysics, 2018Co-Authors: Nicolina Chrysaphi, Eduard P Kontar, Gordon D Holman, Manuela TemmerAbstract:Coronal Mass Ejections (CMEs) are believed to be effective in producing shocks in the Solar corona and the interplanetary space. One of the important signatures of shocks and shock acceleration are Type II Solar Radio Bursts that drift with the shock speed and produce bands of fundamental and higher harmonic plasma Radio emission. An intriguing aspect of Type II Radio Bursts is the occasional split of a harmonic band into thinner lanes, known as band-splitting. Here, we report a detailed imaging and spectroscopic observation of a CME-driven shock producing band-splitting in a Type II Burst. Using the Low Frequency Array (LOFAR), we examine the spatial and temporal relation of the Type II Burst to the associated CME event, use source imaging to calculate the apparent coronal density, and demonstrate how source imaging can be used to estimate projection effects. We consider two widely accepted band-splitting models that make opposing predictions regarding the locations of the true emission sources with respect to the shock front. Our observations suggest that the locations of the upper and lower sub-band sources are spatially separated by $\sim 0.2 \pm 0.05 \, \mathrm{R_\odot}$. However, we quantitatively show, for the first time, that such separation is consistent with Radio-wave scattering of plasma Radio emission from a single region, implying that the split-band Type II sources could originate from nearly co-spatial locations. Considering the effects of scattering, the observations provide supporting evidence for the model that interprets the band-splitting as emission originating in the upstream and downstream regions of the shock front, two virtually co-spatial areas.
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publisher correction imaging spectroscopy of Solar Radio Burst fine structures
Nature Communications, 2018Co-Authors: Eduard P Kontar, A. A. Kuznetsov, A. G. Emslie, B. Alcock, N. L. S. Jeffrey, V. N. Melnik, N. H. Bian, P. SubramanianAbstract:The original version of this article contained errors in Refs 15, 27, 32, 33 and 43, which were incorrectly given with the wrong journal name "Solid Phys." rather than the correct "Sol. Phys.". This has now been corrected in the PDF and HTML versions of the article.
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Imaging spectroscopy of Solar Radio Burst fine structures
Nature Communications, 2017Co-Authors: Eduard P Kontar, A. A. Kuznetsov, A. G. Emslie, B. Alcock, N. L. S. Jeffrey, V. N. Melnik, N. H. Bian, P. SubramanianAbstract:12 Solar Radio observations provide a unique diagnostic of the outer Solar atmosphere. How-13 ever, the inhomogeneous turbulent corona strongly affects the propagation of the emitted 14 Radio waves, so decoupling the intrinsic properties of the emitting source from the effects of 15 Radio-wave propagation has long been a major challenge in Solar physics. Here we report 16 quantitative spatial and frequency characterization of Solar Radio Burst fine structures ob-17 served with the LOw Frequency Array (LOFAR), an instrument with high time resolution 18 that also permits imaging at scales much shorter than those corresponding to Radio-wave 19 propagation in the corona. The observations demonstrate that Radio-wave propagation ef-20 fects, and not the properties of the intrinsic emission source, dominate the observed spatial 21 characteristics of Radio Burst images. These results permit more accurate estimates of source 22 brightness temperatures, and open opportunities for quantitative study of the mechanisms 23 that create the turbulent coronal medium through which the emitted radiation propagates.