Zobrazeno 1 - 10
of 181
pro vyhledávání: '"T. Hagfors"'
Autor:
E. D. Tereshchenko, R. Yu. Yurik, B. Z. Khudukon, M. T. Rietveld, B. Isham, V. Belyey, A. Brekke, T. Hagfors, M. Grill
Publikováno v:
Annales Geophysicae, Vol 24, Pp 1819-1827 (2006)
A high frequency (HF) ionospheric modification experiment was carried out between 25 September and 8 October 2004, using the EISCAT HF transmitter located near Tromsø, Norway. During this experiment the spectra of the stimulated HF sideband waves
Externí odkaz:
https://doaj.org/article/cc307174b6eb4da6a22f2d121a62b6d8
Autor:
E. M. Blixt, T. Grydeland, N. Ivchenko, T. Hagfors, C. La Hoz, B. S. Lanchester, U. P. Løvhaug, T. S. Trondsen
Publikováno v:
Annales Geophysicae, Vol 23, Pp 3-11 (2005)
The generation mechanism for naturally enhanced ion-acoustic echoes is still debated. One important issue is how these enhancements are related to auroral activity. All events of enhanced ion-acoustic echoes observed simultaneously with the EIS
Externí odkaz:
https://doaj.org/article/9b80fa1a388848c7b279c00d2aa5ef7d
Publikováno v:
Annales Geophysicae, Vol 22, Pp 1115-1132 (2004)
Several explanations have been proposed for Naturally Enhanced ion-acoustic Echoes observed at mid- and high-latitude Incoherent Scatter observatories. A decisive measure for distinguishing between these explanations is whether or not simultaneous
Externí odkaz:
https://doaj.org/article/863d91647d3342ea9abb39ead95d11a0
Publikováno v:
Annales Geophysicae, Vol 18, Pp 1145-1153 (2000)
Since the auroral ionosphere provides an important energy sink for the magnetosphere, ionosphere-thermosphere coupling must be investigated when considering the energy budget of the ionosphere-magnetosphere coupling. We present the first Scandinav
Externí odkaz:
https://doaj.org/article/9f6b872755ec46f1a34a4109a6c79bf6
Publikováno v:
Annales Geophysicae, Vol 16, Pp 583-588 (1998)
Ionospheric conductivity is not very easily measured directly. Incoherent scatter radars perhaps offer the best method but can only measure at one point in the sky at any one time and are limited in their time resolution. Statistical models of ave
Externí odkaz:
https://doaj.org/article/ff3156e1325a4dbcba696c08113e8062
Publikováno v:
Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere. 25:475-481
HF induced airglow has been observed at high latitudes on 21 February 1999 during a geomagnetically quiet period (Kp=1). This observation is unique because two patches were generated simultaneously on one occasion. The EISCAT Heating experiment (69.5
Autor:
Aleksandr V. Gurevich, T. Hagfors, Kirill P. Zybin, A. N. Karashtin, H. C. Carlson, Michael C. Kelley
Publikováno v:
Physics Letters A. 251:311-321
The problem of the nonlinear structuring of the modified ionosphere due to the self-focusing of the pump wave on the bunches of striations is investigated. Two main conditions of self-focusing are formulated: (1) propagation of the pump wave quite al
Publikováno v:
Physics Letters A. 246:335-340
The results of electron temperature measurements by incoherent scattering have been considered under the conditions of existence of strong small scale temperature irregularities in the F-region of the ionosphere. A method to determine such local temp
Publikováno v:
Physics Letters A. 239:385-392
Based on the theory of stationary striations created in ionospheric modifications by powerful radio waves, as developed by Gurevich et al. [Phys. Lett. A 206 (1995) 247], the existence of self-oscillations of striations and of a large scale nonlinear
Publikováno v:
Review of Scientific Instruments. 69:578-584
Studies of the relationship between the optical aurorae and the ionospheric electric fields, as observed by the bi-static Scandinavian twin auroral coherent backscatter radar experiment (STARE) and the tri-static European incoherent backscatter radar