Total cross section measurements for positron scattering from acetone

We report results from total cross section measurements for positron-acetone scattering. The energy range of these experiments was 0.2-23 eV, while the energy resolution of our positron beam was ~260 meV. The present data clearly highlight the important role played by the strong permanent dipole moment and significant dipole polarisability of the acetone molecule on the low-energy scattering dynamics of this system. For positron energies above about 6 eV the present data is found to be in quite good agreement with the only other total cross section results available in the literature from the Yamaguchi group, however, at lower energies the level of agreement is rather poor. To the best of our knowledge, no theoretical calculations are currently available for positron-acetone scattering. PACS Codes: 34.80.Uv