2009BaltA..18..193M

We derive NLTE abundances of Na, Mg and Ba in four late-type giants belonging to globular clusters M10 and M71. The obtained relative [Na/Fe] ratios, which were measured only in M10, are positive, with the average value [Na/Fe] = +0.3. The ratios [Mg/Fe] in both clusters are supersolar, +0.15 to +0.28, while [Ba/Fe] scatter between -0.14 and +0.09. Differences between the NLTE abundances derived in this work and those obtained in LTE by Mishenina et al. (2003) are small, typically within ±0.1 dex. We also perform numerical simulations with the CO⁵BOLD 3D hydrodynamical stellar atmosphere code to investigate the influence of convection on the formation of spectral lines used in our NLTE study. For this purpose we use a model of late-type giant with T_eff = 4020 K, logg = 1.0, [M/H] = -1.0 and find that for Na, Mg and Ba the 3D-1D abundance corrections are below ∼0.02 dex. However, their size strongly depends on the value of microturbulent velocity used with the 1D model.