Simple, high current, antimony ion source.
A simple metal ion source capable of producing a continuous, uncontaminated, high current beam of Sb ions is presented. It produced a total ion current of 200 muA at 1 kV extraction voltage. A discharge occurred in the source at a pressure of 6x10(-4) Torr. The ion current extracted from the source increased with the 3/2 power of the extraction voltage. The perveance of the source and ion density in the plasma were 8x10(-9) and 1.8x10(11) cm(-3), respectively.
The Production of High Current, High Quality Beams of Ions and Neutral Particles
This paper describes results obtained with a hot cathode constricted arc plasma source and a single aperture three electrode accel‐decel extraction system. The energy range covered is 5–25 keV for positive ions and 1.7–12.5 keV for neutral beams. Ion currents of the order of 80 mA H3+ and 100 mA He+ at the higher energies have been obtained through a 3.8 cm diam aperture at a distance of 180 cm from the source. The performance as a neutral injector has been evaluated by using the present PHOENIX II experiment. Finally, the relationship between experiment and theory and the limitations of this type of source are discussed.
The Italian Renaissance: Culture and Society in Italy
In this newly revised edition of his widely acclaimed work, Peter Burke presents a social and cultural history of the Italian Renaissance. He discusses the social and political institutions that existed in Italy during the fifteenth and sixteenth centuries, and he analyzes the ways of thinking and seeing that characterized this period of extraordinary artistic creativity. Developing a distinctive approach, the author is concerned not only with the finished works of Michelangelo, Raphael, Leonardo da Vinci, and others, but also with the social background, patterns of recruitment, and means of subsistence of this "cultural elite." He thus makes a major contribution both to our understanding of the Italian Renaissance and to our comprehension of the complex relations between culture and society. An excellent social history of the lives and culture of the artists and artisans which made it possible for the arts to flourish.