We present the preliminary results of VLF
signal perturbations produced due to solar flare. The data were recorded by the
Stanford VLF AWESOME receiver located at National University of Ma-laysia,
Selangor. Two new long distance (>1000 km) VLF paths, JJI-UKM (2700 km) and
NWC-UKM (3300 km) were analyzed simultaneously. Data from the GOES satellite
were used to determine the onset time and type of each of these flares. Results
indicated that all five solar flare events with an X-ray peak flux above 10-5
W/m2 (M-class) were recorded, 37.5% for X-ray flux greater than 10-6 W/m2
(C-class), while the weakest X-ray flux recorded was 2.6 × 10-7 W/m2 (B-class)
with 0.24% probing potentiality. We found a strong positive correlation (0.84)
between solar flare radiation intensity and the values of amplitude and phase
perturbations for both paths. The values of amplitude and phase perturbations
time-correlated with solar flare, varied from 0.2 to 5 dB and 0.15 to 20 degree
respectively. These findings are in complete agreement with previous works and
demonstrate that the data obtained by the UKM AWESOME observation station will
provide addi-tional contribution to the study of ELF/VLF waves phenomena in the
ionosphere/magnetosphere, especially at low latitudes region.
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