ECRIS2010 - List of Authors (Serafino, T.)

Paper

Title

Page

Enhancement of ECR Performances by Means of Carbon Nanotubes Based Electron Guns

114

F. Odorici, M. Cuffiani, L. Malferrari, R. Rizzoli, G.P. Veronese
INFN-Bologna, Bologna, Italy
G. Castro, L. Celona, G. Ciavola, N. Gambino, S. Gammino, D. Mascali, R. Miracoli, F.P. Romano
INFN/LNS, Catania, Italy
T. Serafino
Università di Messina, Messina, Italy

One of the main goals of the scientific community which deals with ECR Ion Sources is the optimization of the Eelectron Energy Distribution Function (EEDF) inside the plasma. The EEDF consists of three different populations (cold, warm and hot electrons): the cold and the warm populations are responsible of the stabilization and of the efficient ionization of the plasma respectively. The presence of the hot population is doubly detrimental: in high frequency sources they lead to the heating of LHe in the superconducting coils’ cryostat and are also useless for the generation of high intensity ion beams, because of their small cross section. Therefore the injection of additional electrons inside the plasma may increase the density of cold and warm electrons, enabling at the same time to reduce the number of the high energy ones. The CANTES experiment tested the use of carbon nanotubes (CNTs) to emit electrons in presence of strong applied electric fields, in order to provide additional electrons to the plasma core. This technique was used with the Caesar ECR ion source, at INFN-LNS, demonstrating that the total extracted ion current is increased and that a relevant reduction of the number of “high energy” electrons (above 100 keV) can be obtained. This last result is even more important, because CNTs may be an effective and reliable tool to permit the operation of ECRIS at large power and high frequencies without any detrimental effect on the source stability and reliability coming from hot electrons. Details of the construction of CNTs based electron gun and their behaviour in plasma environments are presented. Preliminary results in terms of performances of the Caesar ECR ion source and possible future applications will be also discussed.

Poster TUPOT002 [1.914 MB]

Paper	Title	Page
TUPOT002	Enhancement of ECR Performances by Means of Carbon Nanotubes Based Electron Guns	114
	F. Odorici, M. Cuffiani, L. Malferrari, R. Rizzoli, G.P. Veronese INFN-Bologna, Bologna, Italy G. Castro, L. Celona, G. Ciavola, N. Gambino, S. Gammino, D. Mascali, R. Miracoli, F.P. Romano INFN/LNS, Catania, Italy T. Serafino Università di Messina, Messina, Italy
	One of the main goals of the scientific community which deals with ECR Ion Sources is the optimization of the Eelectron Energy Distribution Function (EEDF) inside the plasma. The EEDF consists of three different populations (cold, warm and hot electrons): the cold and the warm populations are responsible of the stabilization and of the efficient ionization of the plasma respectively. The presence of the hot population is doubly detrimental: in high frequency sources they lead to the heating of LHe in the superconducting coils’ cryostat and are also useless for the generation of high intensity ion beams, because of their small cross section. Therefore the injection of additional electrons inside the plasma may increase the density of cold and warm electrons, enabling at the same time to reduce the number of the high energy ones. The CANTES experiment tested the use of carbon nanotubes (CNTs) to emit electrons in presence of strong applied electric fields, in order to provide additional electrons to the plasma core. This technique was used with the Caesar ECR ion source, at INFN-LNS, demonstrating that the total extracted ion current is increased and that a relevant reduction of the number of “high energy” electrons (above 100 keV) can be obtained. This last result is even more important, because CNTs may be an effective and reliable tool to permit the operation of ECRIS at large power and high frequencies without any detrimental effect on the source stability and reliability coming from hot electrons. Details of the construction of CNTs based electron gun and their behaviour in plasma environments are presented. Preliminary results in terms of performances of the Caesar ECR ion source and possible future applications will be also discussed.
	Poster TUPOT002 [1.914 MB]