Abstract: Using the newly established high-energy reaction microscope imaging spectrometer at the Heavy Ion Research Facility in Lanzhou (HIRFL-CSRe), we conducted ionization experiments involving \rmFe^26+ colliding with a helium atom target at energies of 25 and 120 MeV/u. By extracting the time-of-flight spectra of recoil ions, we obtained the single and double ionization cross-section ratios of the helium target at these two energy points. The experimental results indicate that, under the selected perturbation strengths ( \eta=Z_\rmp^ /v_\rmp^ =0.41,\ 0.84 ), the cross-section ratios for single and double ionization processes of the helium target are influenced not only by the projectile velocity but also by the charge state of the projectile, which plays a crucial role in the target ionization mechanism. A comparison with previously published experimental results revealed that, after considering the long-range Coulomb potential, the empirical formula by Knudsen et al. exhibits excellent applicability in both low and high charge state collision processes.