  Single walled carbon nanotubes of 2 nm diameter and 3 to 13 micro meter
length were compressed in Cu bullets and irradiated with positive ions of Cs
with energies from 0.2 to 2.0 keV and subjected to successively increasing Cs
dose. From the mass spectra of the sputtered carbon atoms and clusters as a
function of Cs energy the monitoring of trend of the relative number densities
of the fragmenting species indicates the accumulating damage. Irradiation
induced fragmentation provide clues to the structural changes as a result of
creation of vacancies due to the sputtering of monatomic, diatomic, triatomic
and higher species. Monitoring of the the irradiated target electrical
conductivity provides information of the sequences of the transformation that
may be occurring in the structures of the single walled carbon nanotube as a
function of Cs energy and dose.
