109 research outputs found

    The shock-acoustic waves generated by earthquakes

    Get PDF
    We investigate the form and dynamics of shock-acoustic waves generated by earthquakes. We use the method for detecting and locating the sources of ionospheric impulsive disturbances, based on using data from a global network of receivers of the GPS navigation system and requiring no a priori information about the place and time of associated effects. The practical implementation of the method is illustrated by a case study of earthquake effects in Turkey (August 17, and November 12, 1999), in Southern Sumatera (June 4, 2000), and off the coast of Central America (January 13, 2001). It was found that in all instances the time period of the ionospheric response is 180-390 s, and the amplitude exceeds by a factor of two as a minimum the standard deviation of background fluctuations in total electron content in this range of periods under quiet and moderate geomagnetic conditions. The elevation of the wave vector varies through a range of 20-44 degree, and the phase velocity (1100-1300 m/s) approaches the sound velocity at the heights of the ionospheric F-region maximum. The calculated (by neglecting refraction corrections) location of the source roughly corresponds to the earthquake epicenter. Our data are consistent with the present views that shock-acoustic waves are caused by a piston-like movement of the Earth surface in the zone of an earthquake epicenter.Comment: EmTeX-386, 30 pages, 4 figures, 3 tabl

    Poder do Estado na sociedade moderna: os problemas de compreensão e investigação

    Get PDF
    The article analyzes the problems associated with the understanding of state power, as well as theoretical and methodological innovations and research tools used in the study of this political and legal phenomenon. The authors analyze various directions of the legal, political and sociocultural definition of state power, identify and discuss various dimensions and levels in the conceptualization of the latter. In the context of the paper, the government is as a complex political and legal phenomenon, considered as a specific type of general system of public authority, which is implemented by various political subjects, which have a rigid link to the socio-cultural and territorial space.El artículo analiza los problemas asociados con la comprensión del poder estatal, así como las innovaciones teóricas y metodológicas y las herramientas de investigación utilizadas en el estudio de este fenómeno político y legal. Los autores analizan varias direcciones de la definición legal, política y sociocultural del poder estatal, identifican y discuten varias dimensiones y niveles en la conceptualización de este último. En el contexto del documento, el gobierno es como un fenómeno político y legal complejo, considerado como un tipo específico de sistema general de autoridad pública, que es implementado por varios sujetos políticos, que tienen un vínculo rígido con el contexto sociocultural y territorial. espacio.O artigo analisa os problemas associados à compreensão do poder do Estado, bem como as inovações teóricas e metodológicas e ferramentas de pesquisa utilizadas no estudo desse fenômeno político e jurídico. Os autores analisam várias direções da definição jurídica, política e sociocultural do poder do Estado, identificam e discutem várias dimensões e níveis na conceituação do último. No contexto do trabalho, o governo é um fenômeno político e jurídico complexo, considerado como um tipo específico de sistema geral de autoridade pública, que é implementado por vários sujeitos políticos, que têm um vínculo rígido com as relações socioculturais e territoriais. espaço

    The Planetary Wave Activity in Temperatures of the Stratosphere, Mesosphere and in Critical Frequencies of Ionospheric F2 Layer

    Get PDF
    A large body of experimental evidence lends credit to the existence of a close relationship between ionospheric parameters and the underlying atmosphere. Vertical-incidence ionospheric sounding data and temperature measurements at stratospheric (30 km) and mesospheric (80 km) heights have been used in investigating the interrelation between the occurrence of fluctuations with periods of planetary waves in temperature variations at different heights and in F2 layer critical frequency variations (foF2) under low solar activity conditions for the time interval 2006-2007. The distinctive characteristics of the manifestation of common periodicities of the wave structures under consideration are discussed. The statistically significant periods of stratospheric and mesospheric temperature fluctuations vary from 11 to 49 days, whereas foF2 periodograms show higher-frequency fluctuations with periods of 5, 8, 9, and 10 days. The study revealed a similarity between periodic structures for the variations in the parameters involved

    ANALYSIS OF THE SEISMIC AND IONOSPHERIC EFFECTS OF THE KUDARINSKY EARTHQUAKE ON DECEMBER 9, 2020

    Get PDF
    According to the data obtained on the equipment of the IEC SB RAS complex monitoring base for hazardous geological processes "Buguldeika" (Shared Research Facilities "Geodynamics and Geochronology" of IEC SB RAS) and Shared Research Facilities "Angara" of ISTP SB RAS an analysis of the characteristics of the Kudarinsky earthquake (09.12.2020) and the behaviour of the ionosphere during this event was carried out. The source parameters of the earthquake were obtained – the seismic moment of the earthquake (M0=3.02·1017 N·m), the moment magnitude (Mw=5.6), the source radius (2.43 km), and the stress drop (1.26 MPa).The analysis of the ionosphere behaviour carried out using GPS/GLONASS receivers did not reveal disturbances caused by the Kudarinsky earthquake, which is most likely due to the relatively small magnitude of this earthquake. An analysis of the observation series related to the Kudarinsky earthquake showed the efficiency of using the Core Facilities Centre equipment and complex monitoring bases for studying seismicity, which is the most dangerous natural process for the Baikal region

    АНАЛИЗ СЕЙСМИЧЕСКИХ И ИОНОСФЕРНЫХ ЭФФЕКТОВ КУДАРИНСКОГО ЗЕМЛЕТРЯСЕНИЯ 9 ДЕКАБРЯ 2020 г.

    Get PDF
    According to the data obtained on the equipment of the IEC SB RAS complex monitoring base for hazardous geological processes "Buguldeika" (Shared Research Facilities "Geodynamics and Geochronology" of IEC SB RAS) and Shared Research Facilities "Angara" of ISTP SB RAS an analysis of the characteristics of the Kudarinsky earthquake (09.12.2020) and the behaviour of the ionosphere during this event was carried out. The source parameters of the earthquake were obtained – the seismic moment of the earthquake (M0=3.02·1017 N·m), the moment magnitude (Mw=5.6), the source radius (2.43 km), and the stress drop (1.26 MPa).The analysis of the ionosphere behaviour carried out using GPS/GLONASS receivers did not reveal disturbances caused by the Kudarinsky earthquake, which is most likely due to the relatively small magnitude of this earthquake. An analysis of the observation series related to the Kudarinsky earthquake showed the efficiency of using the Core Facilities Centre equipment and complex monitoring bases for studying seismicity, which is the most dangerous natural process for the Baikal region.По данным, полученным на оборудовании пункта комплексного мониторинга опасных геологических процессов ИЗК СО РАН «Бугульдейка» (Центр коллективного пользования «Геодинамика и геохронология» ИЗК СО РАН) и Центра коллективного пользования «Ангара» ИСЗФ СО РАН, проведен анализ характеристик Кударинского землетрясения (09.12.2020) и поведения ионосферы во время этого события. Получены значения очаговых параметров землетрясения – сейсмический момент землетрясения (M0=3.02·1017 Н·м), моментная магнитуда (Mw=5.6), размеры очага (2.43 км), величина сброшенного напряжения (1.26 МПа).Проведенный с помощью приемников GPS/ГЛОНАСС анализ поведения ионосферы не выявил возмущений, вызванных Кударинским землетрясением, что, вероятнее всего, обусловлено относительно малой магнитудой этого землетрясения. Анализ рядов наблюдений в отношении Кударинского землетрясения показал эффективность использования оборудования центров коллективного пользования и пунктов комплексного мониторинга для исследования сейсмичности, которая является наиболее опасным природным процессом для Байкальского региона

    Feasibility studies of the time-like proton electromagnetic form factor measurements with PANDA at FAIR

    Full text link
    The possibility of measuring the proton electromagnetic form factors in the time-like region at FAIR with the \PANDA detector is discussed. Detailed simulations on signal efficiency for the annihilation of pˉ+p\bar p +p into a lepton pair as well as for the most important background channels have been performed. It is shown that precision measurements of the differential cross section of the reaction pˉ+pe++e\bar p +p \to e^++ e^- can be obtained in a wide angular and kinematical range. The individual determination of the moduli of the electric and magnetic proton form factors will be possible up to a value of momentum transfer squared of q214q^2\simeq 14 (GeV/c)2^2. The total pˉ+pe++e\bar p +p\to e^++e^- cross section will be measured up to q228q^2\simeq 28 (GeV/c)2^2. The results obtained from simulated events are compared to the existing data. Sensitivity to the two photons exchange mechanism is also investigated.Comment: 12 pages, 4 tables, 8 figures Revised, added details on simulations, 4 tables, 9 figure

    First Measurement of Chiral Dynamics in \pi^- \gamma -> \pi^- \pi^- \pi^+

    Full text link
    The COMPASS collaboration at CERN has investigated the \pi^- \gamma -> \pi^- \pi^- \pi^+ reaction at center-of-momentum energy below five pion masses, sqrt(s) < 5 m(\pi), embedded in the Primakoff reaction of 190 GeV pions impinging on a lead target. Exchange of quasi-real photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, t' < 0.001 (GeV/c)^2. Using partial-wave analysis techniques, the scattering intensity of Coulomb production described in terms of chiral dynamics and its dependence on the 3\pi-invariant mass m(3\pi) = sqrt(s) were extracted. The absolute cross section was determined in seven bins of s\sqrt{s} with an overall precision of 20%. At leading order, the result is found to be in good agreement with the prediction of chiral perturbation theory over the whole energy range investigated.Comment: 10 pages, 5 figure

    Measurement of the Longitudinal Spin Transfer to Lambda and Anti-Lambda Hyperons in Polarised Muon DIS

    Get PDF
    The longitudinal polarisation transfer from muons to lambda and anti-lambda hyperons, D_LL, has been studied in deep inelastic scattering off an unpolarised isoscalar target at the COMPASS experiment at CERN. The spin transfers to lambda and anti-lambda produced in the current fragmentation region exhibit different behaviours as a function of x and xF . The measured x and xF dependences of D^lambda_LL are compatible with zero, while D^anti-lambda_LL tends to increase with xF, reaching values of 0.4 - 0.5. The resulting average values are D^lambda_LL = -0.012 +- 0.047 +- 0.024 and D^anti-lambda_LL = 0.249 +- 0.056 +- 0.049. These results are discussed in the frame of recent model calculations.Comment: 13 pages, 7 figure

    Technical Design Report for the PANDA Solenoid and Dipole Spectrometer Magnets

    Full text link
    This document is the Technical Design Report covering the two large spectrometer magnets of the PANDA detector set-up. It shows the conceptual design of the magnets and their anticipated performance. It precedes the tender and procurement of the magnets and, hence, is subject to possible modifications arising during this process.Comment: 10 pages, 14MB, accepted by FAIR STI in May 2009, editors: Inti Lehmann (chair), Andrea Bersani, Yuri Lobanov, Jost Luehning, Jerzy Smyrski, Technical Coordiantor: Lars Schmitt, Bernd Lewandowski (deputy), Spokespersons: Ulrich Wiedner, Paola Gianotti (deputy
    corecore