Sudden Rise in Amplitude of 40 kHz Radio Signal in Relation to Solar Radio Flux (original) (raw)
Related papers
Correlation Structure of Solar Radio Bursts in Accordance with Solar Activity
Journal of Basic and Applied Sciences, 2018
Sun is the nearest star that employs us an opportunity to study the behavior of celestial bodies and their influence on Earth’s atmosphere. This paper investigates the dynamics of Solar Radio Bursts (SRB) with respect to their frequencies type II, type III and Mixed type in accord with Sun Spot Number (SSN) over a span of (1996-2010) base over monthly values. Data from National Oceanic and Atmospheric Administration (NOAA) Space Weather Centre were used in this study. This period covers one full and two partial solar cycles. The ionosphere plays a significant role in radio wave communication, therefore the critical frequency of F 2 layer (foF 2 ), Maximum electron density (N m F 2 ) Plasma frequency (f P ) and Sudden Ionosphere Disturbance (SID) also been included. In various ionospheres quantifications, solar activity such as SSN and 10.7 cm radio flux were used. However SRB influence being considered as a separate variable has not been investigated. The relationship of SRB with ...
Solar radio emission as a disturbance of aeronautical radionavigation
Journal of Space Weather and Space Climate
On November 4th, 2015 secondary air traffic control radar was strongly disturbed in Sweden and some other European countries. The disturbances occurred when the radar antennas were pointing at the Sun. In this paper, we show that the disturbances coincided with the time of peaks of an exceptionally strong (∼105 Solar Flux Units) solar radio burst in a relatively narrow frequency range around 1 GHz. This indicates that this radio burst is the most probable space weather candidate for explaining the radar disturbances. The dynamic radio spectrum shows that the high flux densities are not due to synchrotron emission of energetic electrons, but to coherent emission processes, which produce a large variety of rapidly varying short bursts (such as pulsations, fiber bursts, and zebra patterns). The radio burst occurs outside the impulsive phase of the associated flare, about 30 min after the soft X-ray peak, and it is temporarily associated with fast evolving activity occurring in strong s...
The effects of solar activity: Electrons in the terrestrial lower ionosphere
Journal of the Geographical Institute Jovan Cvijic, SASA
Solar flare X-ray energy can cause strong enhancements of the electron density in the Earth's atmosphere. This intense solar radiation and activity can cause sudden ionospheric disturbances (SIDs) and further create ground telecommunication interferences, blackouts as well as some natural disasters and caused considerable material damage. The focus of this contribution is on the study of these changes induced by solar X-ray flares using narrowband Very Low Frequency (VLF, 3-30 kHz) and Low Frequency (LF, 30-300 kHz) radio signal analysis. The model computation and simulation were applied to acquire the electron density enhancement induced by intense solar radiation. The obtained results confirmed the successful use of applied technique for detecting space weather phenomena such as solar explosive events as well for describing and modeling the ionospheric electron density which are important as the part of electric terrestrial-conductor environment through which external-solar wind (SW) electrons can pass and cause natural disasters on the ground like fires.
Journal of Atmospheric and Solar-Terrestrial Physics, 2014
Effects of two events of X-ray bursts followed by solar proton events (SPEs) occurred on 22 September, 2011 and 06 July, 2012 on the variation of first mode Schumann resonance (SR) frequency monitored at a low latitude station, Agra (Geograph. lat. 27.21N, long. 781E) India are examined. The variation of average first mode SR frequency shows a sudden increase in coincidence with the X-ray bursts and a decrease associated with the peak flux of SPE. The increases in the frequency in the two cases are 8.4% and 10.9% and corresponding decreases are 4.3% and 3.3% respectively. The increases in the frequency are interpreted in terms of growth of ionization in the upper part of D-region ionosphere due to X-ray bursts and decreases during SPE are caused by the high ionization in the lower D-region (altitude about 50-60 km) in the polar region. The variation of SR frequency is observed to be consistent with other observatories at middle and high latitudes. The effects of X-ray flares on the D-region of the ionosphere at low and equatorial latitudes are also examined by analyzing the amplitude data of VLF transmitter signal (NWC, f ¼ 19.8 kHz) monitored at Agra. The flare effect observed prior to sunset hours shows increase of electron density above 60 km in the ionosphere.
Radio Environment Analysis at Balai Cerap KUSZA for Solar Burst Study
International Journal on Advanced Science, Engineering and Information Technology
Solar radio burst study is one of the new researches done in radio astronomy field in Malaysia. Solar radio burst is associated with Coronal Mass Ejections (CMEs). It occurs when magnetic storm collides with Earth's magnetosphere. In this paper, we present the level of radio frequency interference (RFI) at selected sites in Malaysia; ESERI (ECE), Balai Cerap KUSZA (BCK), Sungai Chantek (SGC) and Hentian Serdang (HSRDG) focusing on wideband (30kHz-1000 MHz. The threshold for all selected sites is-76.3741 dBm (7.3887),-74.4022 dBm (9.8143),-73.736 dBm (9.4494) and-66.4082 dBm (13.4290) respectively. This study was done to survey the status of frequency allocation in Malaysia for radio astronomy study. In this frequency ranges, radio astronomical sources found are pulsar, deuterium line (DI) and solar radio burst. These radio astronomical sources can be studied best at BCK compared to other sites. This is important to radio astronomer in Malaysia especially in solar burst detection to identify the best site for observation. This study also may provide RFI database to radio astronomers to refer to before conducting an observation.
The ionospheric scintillation and TEC (Total Electron Content) variations are studied using GPS (Global Positioning System) measurements at an Indian low latitude station Surat (21. 16°N, 72.78°E; Geomagnetic: 12.90°N, 147.35°E), situated near the northern crest of the equatorial anomaly region. The results are presented for data collected during the initial phase of current rising solar activity (low to moderate solar activity) period between January 2009 and December 2011. The results show that within a total number of 656 nighttime scintillation events, 340 events are observed with TEC depletions, Rate of change of TEC (ROT) fluctuations and enhancement of Rate of change of TEC Index (ROTI). A comparison of night-time scintillation events from the considered period reveal strong correlation amongst the duration of scintillation activity in S 4 index , TEC depletion, ROT fluctuations and ROTI enhancement in the year 2011, followed by the year 2010 and least in 2009. The statistical analyses of scintillation activity with enhancement of ROTI also show that about 70-96% scintillation activity took place in equinox and winter months. Moreover, from a nocturnal variation in occurrence of scintillation with (S 4 P 0.2) and enhancement of ROTI with (ROTI P 0.5), a general trend of higher occurrence in pre-midnight hours of equinox and winter seasons is observed in both indices during the year 2011 and 2010, while no significant trend is observed in the year 2009. The results suggest the presence of F-region ionospheric irregularities with scale sizes of few kilometers and few hundred meters over Surat and are found to be influenced by solar and magnetic activity.
Occurrences Rate of Type II and III Solar Radio Bursts at Low Frequency Radio Region 45-870 Mhz
International Letters of Chemistry, Physics and Astronomy, 2013
Observations of type II and III solar bursts indicated that white type III bursts mane appear at any altitude, from the vary lov 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-CALLISTRO network. It was found solar burst type II exploded uite minimum with 1-2 events from 2006 − 2010. However, the data 2011 for solar burst type II increased drastically with 16 events has been recordered. The occurencess of Coronal Mass Ejections (CMEs) events are also increasing up to four times in 2011. Most of both events can be observed in the range of 150 MHz till 500 MHz. Overcall, we can say that the range of photon energy for solar burst type III is between 7.737 x 10-7 eV to 1.596 x 10-6 eV. In the case of solar burst type II, the distribution of energy is much smaller with...
Analysis of type II and type III solar radio bursts
IOP Publishing Ltd 1234567890 ‘’“” 5th International Seminar of Aerospace Science and Technology IOP Publishing IOP Conf. Series: Journal of Physics: Conf. Series 1005 , 2018
Solar radio burst is an arrangement of a frequency space that variation with time. Most of radio burst can be identified in low frequency range such as below 200 MHz and depending on frequencies. Solar radio bursts were the first phenomenon identified in the field of radio astronomy field. Solar radio frequency range is from 70 MHz to 2.2 GHz. Most of the radio burst can be identified in a low frequency range such as below 200 MHz. Properties of low-frequency radio were analyzed this research. There are two types of solar radio bursts were analyzed, named as type II and type III radio bursts. Exponential decay type could be seen in type II, and a linear could be indicated in type III solar radio bursts. The results of the drift rate graphs show the values of each chosen solar radio burst. High drift rate values can be seen in type III solar flares whereas low to medium drift rate values can be seen in type II solar flares. In the second part of the research the Newkirk model electron density model was used to estimate the drift velocities of the solar radio bursts. Although the special origin of the solar radio burst is not known clearly we assumed. The chosen solar radio bursts were originated within the solar radius of 0.9 - 1.3 range from the photosphere. We used power low in the form of (𝑥) = A × 10−𝑏𝑥 were that the electron density related to the height of the solar atmosphere. The calculation of the plasma velocity of each solar radio burst was done using the electron density model and drift rates. Therefore velocity of chosen type II solar radio bursts indicates low velocities. The values are 233.2499 Km s−1, 815.9522 Km s−1 and 369.5425 Km s−1. Velocity of chosen type III solar radio bursts were 1443.058 Km s−1and 1205.05 𝐾𝑚 𝑠−1.
Astrophysics and Space Science, 1996
This article describes the observations of a type III radio burst observed at 103 MHz simultaneously by the two radio telescopes situated at Rajkot (22.3°N, 70.7°E) and Thaltej (23°N, 72.4°E). This event occurred on September 30, 1993 at about 0430 UT and lasted for only half a minute. The event consisted of several sharp spikes in a group. The rise and fall time of these are comparable, however the peaks of individual spikes varied by a factor of four. The comparison of these observations with the data of solar radio spectrograph HiRAS indicates that this was a metric radio burst giving highest emission at about 103 MHz.