We used Fourier transform techniques to identify macroturbulent velocity .
The analysis is done with mictoturbulent velocity and rotation velocity as an unknown quantities .
In order to distinguish the effects of rotation from macroturbulence effects in slowly rotating stars , primarily the main lobe of residual Fourier transforms of the observed lines , which were taken from the solar spectrum and the spectra of two other stars , was used .
This case of Fourier analysis of spectral lines is the most complicated one .
The end results were in a satisfactory agreement with the data obtained using different methods .
The average values of microturbulent , macroturbulent , and rotation velocities were 0.85 , 2.22 , and 1.75 km/s for the Sun as the star ; 0.58 , 1.73 , and 0.78 km/s for HDÂ 10700 ; and 1.16 , 3.56 , and 6.24 km/s for HD 1835 .
It was found that the macroturbulent velocity decreases with height in the atmosphere of the Sun and HDÂ 1835 .
In the case of HD 10700 , the macroturbulent velocity did not change with height , and the determined rotation velocity was two times lower than the one obtained using other methods .
It was concluded that Fourier transform techniques are suitable for determining the velocities in atmospheres of solar-type stars with very slow rotation .