Nanotubes for particle channeling, radiation and electron sources

Carbon nanotubes consist in graphene sheets rolled into seamless hollow cylinders with diameters ranging from 1 nm to about 50 nm. They have been produced as both single walled and multiwalled nanotubes. The diameter of the MWNTs typically ranges from 10 to 50 nm, while the length exceeds 10 mu m. For SWNTs, the diameter is only 1 nm and the length is up to 100 mu m. Nanotubes exhibit unique physical and chemical properties as being a quasi-one dimensional material. The main involvements of the INFN-LNF group in channeling researches are described, i.e. channeling of high energy beams in nanotubes (with the synthesis and characterization of the ordered nanotube samples), crystal extraction and collimation at IHEP (with the design and production of the bent crystals), crystal undulator R&D (with the characterization of the crystal undulator prototypes with SEM and the positron beam). We consider a precise determination of the optimal experimental conditions for channeling of accelerated particles (protons, positrons, photons, neutrons) through micro and nanostructured crystals and films of aligned nanotubes, as promising candidates for producing highly focused beams. (c) 2005 Elsevier B.V. All rights reserved.