Measurement of charge distribution of $^{16}$O through a C-foil for $^{4}$He($^{12}$C,$^{16}$O)$\gamma $ experiment at stellar energy

Measurement of charge distribution of $^{16}$O passed through a C-foil is in progress at Kyushu University tandem laboratory so as to measure $^{4}$He($^{12}$C,$^{16}$O)$\gamma $ cross section at stellar energy by detecting $^{16}$O particles in a charge state. Downstream the helium windowless gas target, we put a thin C-foil to make the charge distribution of $^{16}$O equilibrium. Energy of $^{16}$O is 2-8 MeV, and existing data for the charge distribution of $^{16}$O in the energy range are different to each other by 15 {\%} at most. We measure simultaneously (1) the intensity of a $^{16}$O beam which is incident on a C-foil by counting $^{12}$C recoils by a Si-detector, and (2) the intensity of the $^{16}$O beam in each charge state by a Faraday cup downstream the C-foil. An electric deflector and a magnetic deflector are used to separate a $^{16}$O beam in a charge state from other$^{ }$beams in different charge states.