Comparison of Ionospheric Response to Two Types of Electron Concentration Disturbances

Based on the data of vertical sounding of the ionosphere in Almaty in 2000–2008, the paper deals with the response of the F2-layer to the passage of large-scale traveling ionospheric disturbances (LSTIDs) and the formation of the nighttime enhancements in the electron concentration of the F2-layer. For these two types of perturbations, we compared behavior in the time of the following layer parameters: the height of maximum of the layer (hmF), the height of the bottom of the layer (hbotF), the half-thickness of the layer (Δh = hmF − hbotF), the electron concentration at fixed heights and at the maximum of the layer (NmF), the height profiles of the nighttime enhancement peak-to-peak value of the F2-layer (A), and the height hAm corresponding to the maximum enhancement amplitude. The parameters hmF, hbotF and Δh demonstrate similar dependences associated with the temporal expansion and upward rise of the ionospheric layer and its lowering, accompanied by layer compression, giving an NmF peak at the moment of maximum compression. The common features of the profiles of two types of disturbances are found: the height hAm is always below hmF, there is a good correlation between hAm and hmF, and the difference between hAm and hmF increases linearly with hmF

Scientific program of DERICA — prospective accelerator and storage ring facility for radioactive ion beam research

Studies of radioactive ions (RIs) are the most thriving field of low-energy nuclear physics. In this paper, the concept and the scientific agenda of the prospective accelerator and storage ring facility for RI beam (RIB) research are proposed for a large-scale international project based at the Flerov Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research. The motivation for the new facility is discussed and its characteristics are briefly presented and shown to be comparable to those of advanced world centers, the so-called "RIB factories". In the project, the emphasis is made on studies with short-lived RIBs in storage rings. Aunique feature of the project is the possibility of studying electron-RI interactions in a collider experiment to determine the fundamental properties of nuclear matter, in particular, electromagnetic form factors of exotic nuclei