Is Ni I 676.8 Nm line affected by electron beams in flaring atmospheres ?

Non-LTE simulations for a model Ni I atom in the ambient plasma with solar element abundances are carried out in order to investigate the effects of electron beams on the resulting Ni I 676.8 nm emission during solar flares. The Ni I 676.8 nm line profiles, source functions and departure coefficients were calculated for a period of 10 s after an injection of beams with a variety of their initial parameters. The Ni I 676.8 nm line was found to decrease its depth in the core by about 30% in response to the increase of hydrodynamic heating of the atmosphere during the electron beam precipitation. At the maximum electron flux (6 s in our models), the line profile changes to emissive and stays as such for several seconds returning to the normal absorption profile after the beam is switched off (10 s). Therefore, the line measurements within a timescale of 1 min or longer are more likely not to be strongly affected by the line inversion while more precise (within seconds) temporal measurements on Ni 676.8 nm line profiles of the impulsive phase of flares have to be carefully investigated.