Charge transfer in slow collisions of ${\mathrm{H}}^{+}$ with Na

We reexamined charge-transfer cross sections for protons colliding with $\mathrm{Na}\mathrm{}\left(3s\right)\mathrm{}$ atoms for collision energies from the threshold at 1.7 eV to 40 eV using the recently developed hyperspherical close-coupling method. Our results disagree with the recent calculations by Dutta et al. [Phys. Rev. A 63, 022709 (2001)], but are in good agreement with the earlier calculations of Croft and Dickinson [J. Phys. B 29, 57 (1996)] except at energies below 3 eV. Our calculations support the doubt on the experimental data of Kushawaha.