In the literature, the values are often stated as "offset", "carrier offset", "offset of the spin-lock pulse" with values given in Hz, and can have values from 0-500 to 10-20.000 Hz.<br>
These values reflects offset frequencies to the carrier frequency, and in relax is noted as "Spin-lock offset, the frequency of of the rf field" : $\textbfmathbf{\omega_{rf}}$.
Relax needs input in ppm, and converts to the rad/s, with the following function calls.