Obiettivo This project is devoted to the multi-disciplinary study of a particular class of ULF waves in the near-Earth space: medium-scale Alfven waves (with azimuthal wave numbers m>>1). Their spatial structure is mainly determined by MHD effects, but due to large azimuthal electric field component the high-m waves resonantly interact with energetic particles. The proposed project comprises complementary and interrelated theoretical and experimental tasks. Adequate theoretical description of medium-scale Alfven waves demands a hybrid approach, where kinetic effects are included in MHD equations. We are going to elaborate the theory of a new ULF phenomenon - the Alfvenic waveguide, where the wave energy is trapped between the conjugate ionospheres and cut-off shells, and is channeled along azimuth. A new two-step conception of the Alfven wave generation will be elaborated: (1) non-steady current of drifting energetic particles generates in a non-resonant way broadband supra-thermal hydromagnetic fluctuations; (2) a resonant instability provides amplification of narrow-band waves from these turbulent "embryos". This conception will be applied to the interpretation of ULF wave excitation during magnetic storms. We intend to develop a unified gyro-kinetic theory describing both transverse spatial structure and growth rate of coupled Alfven and compressional modes taking into account the plasma density inhomogeneity across magnetic shells and along field lines, finite anisotropic pressure, and resonant drift-bounce wave-particle interaction. Combined data from multi-satellite CLUSTER magnetic, electric, and particle sensors, ionospheric radars, and ground magnetometer array will be analyzed to elucidate the spatio-temporal structure of medium-scale waves and compare it with the elaborated theoretical models. This project will enrich the physics of nighttime ULF waves and transients by developing a new analytical theory to characterize the interaction of Alfven waves with different types of resistive layers that may occur in the nightside magnetosphere: the auroral acceleration region; turbulent layers with anomalous conductivity; and thin current sheets with steep bending of magnetic field lines embedded in high-pressure plasma. This theory will promote the notion on the scale-dependent coupling between the magnetosphere and ionosphere. The spatial structure of intense electromagnetic bursts detected by CLUSTER on field lines conjugate to auroral arcs (as determined from ground auroral cameras) will be examined to verify the hypothesis that medium-scale Alfven waves provide energy to the auroral arc intensification. Coordinated multi-instrument analysis will be performed in search of localized transient response to an occurrence of anomalous resistivity on auroral field lines and of the magnetotail-related ionospheric ULF signatures. The project will provide first comprehensive review of meso-scale electromagnetic phenomena in the near-Earth environment. Parole chiave Electromagnetic Processes Plasma Instabilities & Non-Linear Phenomena Upper Atmospheric Physics Programma(i) IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993- Argomento(i) Data not available Invito a presentare proposte Data not available Meccanismo di finanziamento Data not available Coordinatore TECHNISCHE UNIVERSITÄT BRAUNSCHWEIG Contributo UE Nessun dato Indirizzo MENDELSSOHNSTRASSE, 3 BRAUNSCHWEIG Germania Mostra sulla mappa Costo totale Nessun dato Partecipanti (5) Classifica in ordine alfabetico Classifica per Contributo UE Espandi tutto Riduci tutto INSTITUTE OF SOLAR-TERRESTRIAL PHYSICS Russia Contributo UE Nessun dato Indirizzo LERMONTOV STR., 126 IRKUTSK Mostra sulla mappa Costo totale Nessun dato ROYAL INSTITUTE OF TECHNOLOGY (KTH) Svezia Contributo UE Nessun dato Indirizzo TEKNIKRINGEN, 31 STOCKHOLM Mostra sulla mappa Costo totale Nessun dato SPACE RESEARCH INSTITUTE (IKI) Russia Contributo UE Nessun dato Indirizzo PROFSOYUZNAYA, 84/32 MOSCOW Mostra sulla mappa Costo totale Nessun dato UNITED INSTITUTES OF PHYSICS OF THE EARTH RAS Russia Contributo UE Nessun dato Indirizzo B. GRUZINSKAYA, 10 MOSCOW Mostra sulla mappa Costo totale Nessun dato University of Leicester Regno Unito Contributo UE Nessun dato Indirizzo University Road LE1 7RH LEICESTER Mostra sulla mappa Collegamenti Sito web Opens in new window Costo totale Nessun dato