Scintillation light produced by low-energy beams of highly-charged ions

Measurements have been performed of scintillation light intensities emitted from various inorganic scintillators irradiated with low-energy beams of highly-charged ions from an electron beam ion source (EBIS) and an electron cyclotron resonance ion source (ECRIS). Beams of xenon ions Xe$^{q+}$ with various charge states between $q$=2 and $q$=18 have been used at energies between 5 keV and 17.5 keV per charge generated by the ECRIS. The intensity of the beam was typically varied between 1 and 100 nA. Beams of highly charged residual gas ions have been produced by the EBIS at 4.5 keV per charge and with low intensities down to 100 pA. The scintillator materials used are flat screens of P46 YAG and P43 phosphor. In all cases, scintillation light emitted from the screen surface was detected by a CCD camera. The scintillation light intensity has been found to depend linearly on the kinetic ion energy per time deposited into the scintillator, while up to $q$=18 no significant contribution from the ions' potential energy was found. We discuss the results on the background of a possible use as beam diagnostics e.g. for the new HITRAP facility at GSI, Germany.Comment: 6 pages, 8 figure

Rethinking Workers' Education in Africa

The employment patterns and trends as well as technological changes have been the most important factors in broadening the need to rethink workers' education in Africa. Workers' education more than before, now has a particularly critical role to play in the various Africa rapidly changing societies by providing knowledge and information that the working class people need in order to cope with the changing conditions. Obviously, the role of workers' education in Africa assumes greater and greater importance. Wide ranges of capabilities are required nowadays to deal with emerging technological challenges. This shift of emphasis involved in looking at 'wider education' or 'development education' for increased sociooolitical and economic roles rather than 'education for industry' or 'technical utilitarian education', immediately makes it clear that the task is vast and challenging, requiring a new perspective. It is on this basis, that this paper therefore attempts the possibility of rethinking workers' education as constituting the most important form of human capital formation in African countries. Thus a rejuvenated, complicated, comprehensive and highly integrated facet of workers' education is seen as a key factor in creating an African labour force that will be able to play an effective role in the development of the various African nations