In-flight calibration of the Cluster PEACE sensors

The Plasma Electron and Current Experiment (PEACE) instruments operate on all four of the Cluster spacecraft and measure the 3-D velocity distribution of electrons in the energy range from 0.59 eV to 26.4 keV during each spacecraft spin. Pitch angle distributions and moments of the velocity distribution are also produced. As the mission has progressed, the efficiency of the detectors has declined. Several factors may play a role in this decline such as exposure to radiation, high electron fluxes and spacecraft thruster firings. To account for these variations, continuous in-flight calibration work is essential. The purpose of this paper is to describe the PEACE calibration parameters, focussing in particular on those that vary over time, and to describe the methods which are used to determine their evolution

QDB: A new database of plasma chemistries and reactions

One of the most challenging and recurring problems when modeling plasmas is the lack of data on the key atomic and molecular reactions that drive plasma processes. Even when there are data for some reactions, complete and validated datasets of chemistries are rarely available. This hinders research on plasma processes and curbs development of industrial applications. The QDB project aims to address this problem by providing a platform for provision, exchange, and validation of chemistry datasets. A new data model developed for QDB is presented. QDB collates published data on both electron scattering and heavy-particle reactions. These data are formed into reaction sets, which are then validated against experimental data where possible. This process produces both complete chemistry sets and identifies key reactions that are currently unreported in the literature. Gaps in the datasets can be filled using established theoretical methods. Initial validated chemistry sets for SF 6 /CF 4 /O 2 and SF 6 /CF 4 /N 2 /H 2 are presented as examples

METHODOLOGY OF JUSTIFICATION THE TYPE AND EVALUATION OF QUALITY GROUP SEARCH OF DEFECTS IN THE REPAIR RADIO-ELECTRONIC MEANS

Context. Radioelectronic devices are continuously complicated, which complicates the process of restoring their efficiency, when the diagnosis consumes the largest labor costs and time. Therefore, the promising direction of increasing the efficiency of the renewal of modern electronic means is to improve diagnostic support.Objective. The purpose of the article is to increase the efficiency of diagnostic provision of radio electronic means at the expense of a reasonable choice of the type of group search of defects.Method. In the work analytical studies of conditional algorithms of diagnosis with the use of graph theory theory, probability theory and the theory of discrete search – a scientific discipline that studies the diagnostic process when restoring the efficiency of complex technical objects with varying degrees of damage through research and optimization of procedures and algorithms for detection of a priori – in unknown number of elements with given properties on the finite structurally-bounded set according to some criterion.Results. The method of choosing the type of algorithm of group search of defects at given restrictions and assumptions on the criterion of minimum labor costs on the basis of generalization of the graph-analytical model of group search of defects with quantitative estimation of probabilistic, time and cost indicators of the quality of the process of diagnosing radioelectronic devices with different degree of damage, which allows to pre-substantiate the most appropriate algorithm for group defects search for use in the development of diagnostic support for modern radio ectronic means.Conclusions. For the first time, various types of group search of defects with a quantitative estimation of the efficiency of their use depending on the features of radio-electronic means and the conditions for their restoration of efficiency are considered in a complex way

The virtual atomic and molecular data centre (VAMDC) consortium

The Virtual Atomic and Molecular Data Centre (VAMDC) Consortium is a worldwide consortium which federates atomic and molecular databases through an e-science infrastructure and an organisation to support this activity. About 90% of the inter-connected databases handle data that are used for the interpretation of astronomical spectra and for modelling in many fields of astrophysics. Recently the VAMDC Consortium has connected databases from the radiation damage and the plasma communities, as well as promoting the publication of data from Indian institutes. This paper describes how the VAMDC Consortium is organised for the optimal distribution of atomic and molecular data for scientific research. It is noted that the VAMDC Consortium strongly advocates that authors of research papers using data cite the original experimental and theoretical papers as well as the relevant databases