Carbon nanotube foils for electron stripping in tandem accelerators

Carbon nanotube technology has rapidly advanced in recent years, making it possible to create meter-long, ∼4 cm wide films of multi-walled tubes of less than 3 μg/cm2 areal density in a bench top open-air procedure. The physical properties of individual carbon nanotubes have been well established, equaling or surpassing electrical and thermal conductivity and mechanical strength of most other materials, graphite in particular. The handling and transport of such nanotube films, dry-mounted self-supporting on metal frames with several cm2 of open area, is problem-free: the aerogel films having a volumetric density of about 1.5 mg/cm3 survived the trip by car and air from Dallas to Oak Ridge without blemish. In this paper we will present the results of first tests of these nanotube films as electron stripper media in a tandem accelerator. The tests were performed in the Model 25 URC tandem accelerator of the Holifield radioactive ion beam facility (HRIBF) at Oak Ridge National Laboratory. We will discuss the performance of nanotube films in comparison with chemical vapor deposition and laser-ablated carbon foils.