Signal correlation in the tandem of a spin oscillator and microwave frequency discriminator with laser-pumped alkali atoms

We have studied the influence of low-frequency noise on the stability of resonance frequency of a self-oscillating magnetometer on $^{87}$Rb vapor with simultaneous monitoring of the signal of radio-optical resonance on the magnetic-field-dependent microwave transition under laser pumping at the $D_2$ line of the head doublet. The difference of synchronous records of detected signals reduced to the same scale in magnetic field units was processed to determine the Allan variance as a function of the averaging time. The correlation coefficient characterizing the coupling of detected signals determined by the pumping rate and intensity of radio fields generated in the region of the absorption chamber. The self-oscillating magnetometer can only operate provided that there is laser tuning to the long-wavelength component of the electric-dipole transition.