76 research outputs found

    Anomalous effect in Schumann resonance phenomena observed in Japan, possibly associated with the Chi-chi earthquake in Taiwan

    Get PDF
    The Schumann resonance phenomenon has been monitored at Nakatsugawa (near Nagoya) in Japan since the beginning of 1999, and due to the occurance of a severe earthquake (so-called Chi-chi earthquake) on 21 September 1999 in Taiwan we have examined our Schumann resonance data at Nakatsugawa during the entire year of 1999. We have found a very anomalous effect in the Schumann resonance, possibly associated with two large land earthquakes (one is the Chi-chi earthquake and another one on 2 November 1999 (Chia-yi earthquake) with a magnitude again greater than 6.0). Conspicuous effects are observed for the larger Chi-chi earthquake, so that we summarize the characteristics for this event. The anomaly is characterized mainly by the unusual increase in amplitude of the fourth Schumann resonance mode and a significant frequency shift of its peak frequency (~1.0Hz) from the conventional value on the <i>B<sub>y</sub></i> magnetic field component which is sensitive to the waves propagating in the NS meridian plane. Anomalous Schumann resonance signals appeared from about one week to a few days before the main shock. Secondly, the goniometric estimation of the arrival angle of the anomalous signal is found to coincide with the Taiwan azimuth (the unresolved dual direction indicates toward South America). Also, the pulsed signals, such as the Q-bursts, were simultaneously observed with the "carrier" frequency around the peak frequency of the fourth Schumann resonance mode. The anomaly for the second event for the Chia-yi earthquake on 2 November had much in common. But, most likely due to a small magnitude, the anomaly appears one day before and lasts until one day after the main shock, with the enhancement at the fourth Schumann resonance mode being smaller in amplitude than the case of the Chi-chi earthquake. Yet, the other characteristics, including the goniometric direction finding result, frequency shift, etc., are nearly the same. Although the emphasis of the present study is made on experimental aspects, a possible generation mechanism for this anomaly is discussed in terms of the ELF radio wave scattered by a conducting disturbance, which is likely to take place in the middle atmosphere over Taiwan. Model computations show that the South American thunderstorms (Amazon basin) play the leading role in maintaining radio signals, leading to the anomaly in the Schumann resonance

    Universal and local time components in Schumann resonance intensity

    Get PDF
    We extend the technique suggested by Sentman and Fraser (1991) and discussed by Pechony and Price (2006), the technique for separating the local and universal time variations in the Schumann resonance intensity. Initially, we simulate the resonance oscillations in a uniform Earth-ionosphere cavity with the distribution of lightning strokes based on the OTD satellite data. Different field components were used in the Dayside source model for the Moshiri (Japan, geographic coordinates: 44.365° N, 142.24° E) and Lehta (Karelia, Russia, 64.427° N, 33.974° E) observatories. We use the extended Fourier series for obtaining the modulating functions. Simulations show that the algorithm evaluates the impact of the source proximity in the resonance intensity. Our major goal was in estimating the universal alteration factors, which reflect changes in the global thunderstorm activity. It was achieved by compensating the local factors present in the initial data. The technique is introduced with the model Schumann resonance data and afterwards we use the long-term experimental records at the above sites for obtaining the diurnal/monthly variations of the global thunderstorms

    Algorithm for choosing the place for the global Schumann resonance observatory

    Get PDF
    We suggest an algorithm for choosing the position for the observatory of the Schumann resonance (SR). The main goal of future measurements is to estimate the intensity of the global thunderstorm activity which is the main source of the electromagnetic energy in the extremely low frequency (ELF) band from a few Hertz to some tens of Hertz. Our analyses is based on the numerical modeling of the SR background signal. It is shown that the quality of the data dramatically depends on the position of the field-site, and the polar regions are the most promising candidates for SR explorations

    The effect of a gamma ray flare on Schumann resonances

    Get PDF
    We describe the ionospheric modification by the <I>SGR</I> 1806-20 gamma flare (27 December 2004) seen in the global electromagnetic (Schumann) resonance. The gamma rays lowered the ionosphere over the dayside of the globe and modified the Schumann resonance spectra. We present the extremely low frequency (ELF) data monitored at the Moshiri observatory, Japan (44.365° N, 142.24° E). Records are compared with the expected modifications, which facilitate detection of the simultaneous abrupt change in the dynamic resonance pattern of the experimental record. The gamma flare modified the current of the global electric circuit and thus caused the "parametric" ELF transient. Model results are compared with observations enabling evaluation of changes in the global electric circuit

    DNA waves and water

    Full text link
    Some bacterial and viral DNA sequences have been found to induce low frequency electromagnetic waves in high aqueous dilutions. This phenomenon appears to be triggered by the ambient electromagnetic background of very low frequency. We discuss this phenomenon in the framework of quantum field theory. A scheme able to account for the observations is proposed. The reported phenomenon could allow to develop highly sensitive detection systems for chronic bacterial and viral infections.Comment: Invited talk at the DICE2010 Conference, Castiglioncello, Italy September 201

    Bounds on Lorentz and CPT Violation from the Earth-Ionosphere Cavity

    Full text link
    Electromagnetic resonant cavities form the basis of many tests of Lorentz invariance involving photons. The effects of some forms of Lorentz violation scale with cavity size. We investigate possible signals of violations in the naturally occurring resonances formed in the Earth-ionosphere cavity. Comparison with observed resonances places the first terrestrial constraints on coefficients associated with dimension-three Lorentz-violating operators at the level of 10^{-20} GeV.Comment: 8 pages REVTe

    WAVEFORMS OF NATURAL ELF RADIO SIGNALS

    No full text
    • …
    corecore