Effects of Solar Eclipse on Long Path VLF Transmission
نویسندگان
چکیده
The variations of phase and amplitude of a subionospheric transmitted signal at frequency 19.8 kHz from North West Cape, Australia (latitude: 21.82◦S; longitude: 114.16◦E) measured at Kolkata (latitude: 22.56◦N, longitude: 88.5◦E) during the period of solar eclipse (partial, 91.1%) on July 22, 2009 will be presented in this paper. The variations in amplitude are quite significant than the usual ambient values of the adjacent 5 days of the day of eclipse for the same period. During eclipse, the height of reflection of VLF (very low frequency) signal has been increased by 3 km. The conductivity parameter and the sharpness parameter are calculated using phase and amplitude variation of VLF signal. Plausible explanations of these changes in amplitude and phase are presented. The waveguide parameters, viz., conductivity parameter (ωr) and sharpness parameter (β) related to VLF propagation in the Earth-ionosphere waveguide are considered to be responsible for signal attenuation. PACS codes: 92.60.Pw, 94.20.Vv
منابع مشابه
Investigation and Simulation of the Effects of Dispersion and Transmittance angles on the Solar Cells Quantum Efficiency
In this paper the effects of transmittance, dispersion angle and diffusion length on the quantum efficiency of solar cells (QESC) have been simulated and investigated. Optical path technic is used for simulation. The results show that base thickness, diffusion length, dispersion angle, number of optical confinement path and transmission angles have an extremely effects on the QESC. Simulation r...
متن کاملSolar flare effects on D-region ionosphere using VLF measurements during low- and high-solar activity phases of solar cycle 24
The effects of solar flares on the propagation of subionospheric VLF signals from NWC and NLK transmitter stations monitored at a low-latitude station, Suva (18.2°S, 178.4°E), Fiji, between December 2006 and December 2010 (an unprecedented solar minimum of solar cycles 23 and 24) and between January 2012 and December 2013 (moderate solar activity at the peak of solar cycle 24) have been analyze...
متن کاملCoordinated weather balloon solar radiation measurements during a solar eclipse
Solar eclipses provide a rapidly changing solar radiation environment. These changes can be studied using simple photodiode sensors, if the radiation reaching the sensors is unaffected by cloud. Transporting the sensors aloft using standard meteorological instrument packages modified to carry extra sensors, provides one promising but hitherto unexploited possibility for making solar eclipse rad...
متن کاملModeling solar flare induced lower ionosphere changes using VLF/LF transmitter amplitude and phase observations at a midlatitude site
Remote sensing of the ionosphere bottom using long wave radio signal propagation is a still going stro g and inexpensive method for continuous monitoring purposes. We present a propagation model describing the time development of solar flare effects. Based on monitored amplitude and phase data from VLF/LF transmitters gained at a mid-latitude site during the currently increasing solar cycle no....
متن کاملThe ionospheric responses to the 11 August 1999 solar eclipse: observations and modeling
A total eclipse occurred on 11 August 1999 with its path of totality passing over central Europe in the latitude range 40–50 N. The ionospheric responses to this eclipse were measured by a wide ionosonde network. On the basis of the measurements of foE, foF1, and foF2 at sixteen ionosonde stations in Europe, we statistically analyze the variations of these parameters with a function of eclipse ...
متن کامل