Papers by ZETY SHARIZAT HAMIDI
The solar flare and Coronal Mass Ejections (CMEs) are well known as one of the most massive
erupt... more 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.
This article aims to present the significant role of several parameters of a Log Periodic Dipole ... more This article aims to present the significant role of several parameters of a Log Periodic Dipole Antenna (LPDA) to perform a better observation of solar radio burst. This antenna is constructed with (19) elements of different sizes covers from 45 MHz to 870 MHz. The performance of the antenna was carried out at the National Space Agency (PAN), Sg. Lang, Banting Selangor by connecting to the CALLISTO spectrometer. We use an input impedance, R 0 = 50 Ω for this LPDA antenna. Since the burst level above the background sky is 0.41 dB, the flux density of the burst is 5.5 x 10 -21 W/m 2 /Hz. Based on the analysis, the gain of the antenna is 9.3 dB. This antenna potentially captures a signal that covers about 0.08 m 2 area of the Sun. It was found that the temperature of the burst that detected at the feed point of the antenna is 32 K. Nevertheless, the signal becomes decrease to 28.75 K while by the CALLISTO (Compound Low Cost Low Frequency) spectrometer as a receiver. The isotropic source spectral power is 1576 W/Hz. We conclude that this antenna is appropriate to observe the Sun activity at low frequency radio region.
Sun is the nearest star in our solar system. Every occurrence in the Sun gives significant impact... more Sun is the nearest star in our solar system. Every occurrence in the Sun gives significant impact towards us. In this research we try to obtain Wolf number, class of sunspots and measuring rotation period. As Wolf number is index to Sun’s activity. Sun’s activity indicate climate changes on Earth and space weather.
Observatories (CALLISTO) is a global network of spectrometer system with the purpose to observe t... more Observatories (CALLISTO) is a global network of spectrometer system with the purpose to observe the Sun's activities. There are 25 stations that are used for this purpose. Radio Frequency Interference (RFI) is a major obstacle when performing observation with CALLISTO. We have confirmed at least 2 stations out of 10 stations with a complete overview spectral (OVS) made available to us showed clear detection of these consistent types of RFI for each specific region. In Malaysia, these RFI are also clearly detected. The major RFI affecting CALLISTO within radio astronomical windows below 1 GHz are local electronic system specifically radio navigation (at 73.1 MHz and 75.2 MHz), broadcasting (at (i) 151 MHz, (ii) 151.8 MHz and 152 MHz), aeronautical navigation (at (i) 245.5 MHz, (ii) 248.7 MHz and (iii) 249 MHz and fixed mobile at (i) 605 MHz, (ii) 608.3 MHz, (iii) 612.2 MHz, (iv) 613.3 MHz). It is obviously showed that all sites within this region are free from interference at 320-330 MHz and is the best specific region to be considered for solar burst monitoring. We also investigate the effect of RFI on detection of solar burst. We have considered type III solar bursts on 9 th March 2012 in order to measure the percentage of RFI level during the solar burst. The RFI level is as low as 6.512 % to 80.769 % above solar burst detection.
Comparison of the Radio Frequency Interference (RFI) in the Region of Solar Burst Type III Data At Selected CALLISTO Network
Important results of the Radio Frequencies Interference (RFI) at the National Space Centre, Sg La... more Important results of the Radio Frequencies Interference (RFI) at the National Space Centre, Sg Lang Selangor, Malaysia has been reported. In order to make sure that the data of solar monitoring in radio region is reliable, we need to study the variation of interference and the possible sources that contribute to this interference. This data has been taken from 1-2000 MHz at the main site of installation e-CALLISTO system. The study is one of a main part of an initiative of e-CALLISTO networking research in order to identify the main RFI sources and to monitor continuously the behavior of the RFI at the site. Our main objective is to qualify the potential of monitoring a continuous radio emission of the Sun. This work is also an initiative of the International Space Weather Initiative (ISWI) project where Malaysia is one of the countries that joined the e-CALLISTO network. Due to our results this site showed the positive impact for the solar monitoring purpose. It is hoped that the survey will continue from time to time in a consistent mode so that any polluted signal for radio astronomy purpose can be protected. Overall, we can still get a good solar burst data, especially at 40-400 MHz. Perhaps, we can contribute the good data for solar burst monitoring towards the maximum cycle beginning the end of this year 2013.
Matahari sebagai jasad samawi yang memainkan peranan penting kepada kehidupan. Maklumat tentang M... more Matahari sebagai jasad samawi yang memainkan peranan penting kepada kehidupan. Maklumat tentang Matahari perlu diperolehi bagi menghubungkaitkan kesan Matahari terhadap Bumi. Salah satu cara untuk memahami Matahari adalah dengan memantau tompok Matahari.
Variation of solar bursts due to solar flares such as type an isolated type III , a complex type ... more Variation of solar bursts due to solar flares such as type an isolated type III , a complex type III, U is being highlighted. These bursts occurred on 9th March 2012 at the National Space Centre, Sg. Lang, Selangor, Malaysia Here, we study a unique case with a combination of two types burst associated with solar flare and CMEs. Our observation is focused on the low frequency region starting from 150 MHz till 400 MHz. We found that a solar flare type solar flare type M 6.3 which occurred in active region AR 1429 starting from 3:32 UT and ending at 05:00 UT. The flare has been confirmed to be the largest flare since 2005. Some physical parameters will be measured. We then compared our results with X-ray data from NOAA Space Weather Prediction Centre (SWPC)
Space weather is very synonymous with the activities of our nearest star, the Sun. Recently; the ... more Space weather is very synonymous with the activities of our nearest star, the Sun. Recently; the space weather program has stimulated interest in this issue. The main reason is due to the extreme climate change and towards to the solar maximum at the beginning of 2013. It is believed that the Earth environment has a close connection with Sun activities, such as solar flares and Coronal Mass Ejections (CMEs). However, to prove it is not an easy way. The dynamism of the Sun also still is not easy to be understood. To improve our understanding of the solar activities, a new experimental approach by 24 hours monitoring has been done since 2007 by e-CALLISTO network. This work is a part of International of Space Weather Initiative Program (ISWI). As one of equatorial country, Malaysia also could contribute in terms of a consistent 12 hours monitoring and one of the earliest sites that observe the Sun every day. Here, we will highlight the role of our site, mechanism and implications of Sun activities to the Earth. It is hoped to meet the current knowledge about the Sun with this new method of experimental approach .
Solar studies in radio emission and optical photometry
In this article, we have recognized a Radio Frequency Interference (RFI) sources that can potenti... more In this article, we have recognized a Radio Frequency Interference (RFI) sources that can potentially affect for radio astronomical observation. The main objective of this surveying is to test and qualify the potential of radio astronomical sources that can be observed in Malaysia generally. Analysis process focuses on the high sources that contribute the pollution and the significant region that can be considered for astronomical purpose beginning 1-2000 MHz. It was found that 13 individual sources contribute as a noise and mostly are telecommunication and radio navigation applications. We then compared of the RFI profiles based on three different periods in order to observe the variety of the signals. The main regions that still excellent to do an observation are: 13.36 -13.41 MHz (solar), (25.55-25.67) MHz (Jupiter) and (37.50-38.25) MHz (Continuum) respectively. This work is also an initiative of the International Space Weather Initiative (ISWI) project where Malaysia is one of the countries that involve in e-CALLISTO (Compound Astronomical Low Cost Low Frequency Transportable Observatory) network project. Some suggestions are recommended in order to improve the quality of the radio frequency profile.
The formation of two different solar bursts, type III and V in one solar flare event is presented... more The formation of two different solar bursts, type III and V in one solar flare event is presented. Both bursts are found on 19 th 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/cm 3 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 differently. It is believed that the ejection of particles in a type III burst is higher than solar burst type V.
This review covers the most recent status of e-Callisto research collaboration under ISWI (Intern... more This review covers the most recent status of e-Callisto research collaboration under ISWI (International Space Weather Initiative) in 2011. The research is a part of initiative of United Nations together with NASA in order to support developing countries participating in 'Western Science' research. Starting from 2007, the objective to monitor the solar activities (solar flares) within 24 hours all over the world is positively turned to reality. By using the same CALLISTO spectrometer within 45-870 MHz, designing and leading by Christian Monstein from ETH Zurich, Switzerland, this research project is the one of successful project under ISWI program. Malaysia becomes the 19th countries that involve this research. We started by proposed this research in early 2011, through National as universities collabarator. Some basic experimental such the investigations of Radio Frequency Interference (RFI) and the construction of Log Periodic Antenna have been done in order to setup the research. We have decided to setup the e-Callisto project at National Space Agency, Banting Malaysia due to the strategic location and quite freely from interference. The basic attention in this paper is to highlight the history, current activities, some achievement and the future plan that we will do in short term and long term project.
INPUMA Conference, Jul 10, 2011
This paper tries to delve the meaning of human development at a glance. Currently, HDI does not d... more This paper tries to delve the meaning of human development at a glance. Currently, HDI does not determine completely the concept of human development. A few scholars had proposed definition regarding this matter. However, the authors believe human development is must be something beyond conventional definition. What is more, the authors attempt to answer by providing a set of thought on human development from Islamic consideration. It is a reflection of a fact, as we "manufactured" by Allah and surely we have to use the given "manual". Through understanding of the set, sustainability appears as its application. This paper is no more a small step for man yet it tries to shed light on this matter.
This initiative is to modify so that it will be more portable and established enough. We choose v... more This initiative is to modify so that it will be more portable and established enough. We choose value of 0.08 spacing factor τ= 0.8 as a directivity of antenna. The performance of this antenna will also be discussed.
Logarithmic periodic dipole antenna (LPDA) was constructed for monitoring Sun in the range of (45... more Logarithmic periodic dipole antenna (LPDA) was constructed for monitoring Sun in the range of (45 -870) MHz to precisely match the solar monitoring requirements. In our work, we choose rod aluminium's type as a conductor with nineteenth (19) elements of different sizes. Beside established construction techniques, several test setups have done to make sure that we possibly obtain a good data. The performance testing has been done at National Space Agency (PAN), Sg. Lang, Banting Selangor by connecting to the CALLISTO spectrometer. In this case, we choose input impedance, R 0 = 50 ohm for this LPDA antenna. We also select element factor (τ) and spacing factor (σ) give in the subtended angle of 3.43 degrees. As a result, a bandwidth ratio (B = 870 MHz /45MHz) of 19.33 gives a bandwidth as 2.14. The power flux density of the burst is 4.53841 x 10 -21 W/m 2 Hz. From the evaluation, we found that the signal to noise ratio is 3.9 dB. Although there are still needs to be improved, this construction of LPDA is considered successful and suitable for to observe the Sun activities at low frequencies.
Ground Based Astronomical Spectroscopy
A short term variation of solar flare in nine (9) months (January 2010 to September 2010) is pres... more A short term variation of solar flare in nine (9) months (January 2010 to September 2010) is presented. This paper review and analyze the correlation between radio flux strength measurement and solar flare in X-ray region. The radio flux measurement data were taken from the National Research Council;
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Papers by ZETY SHARIZAT HAMIDI
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.