Fig. 6: Calibration of the comagnetometer.
From: Constraints on exotic spin-velocity-dependent interactions
a The comagnetometer is rotated by a rotary platform. The sensitive axis (\(\hat{y}\)) of comagnetometer is directed along different direction. Hence, the projection of Earth rotation along \(\hat{y}\) can be used to calibrate the comagnetometer. β is the latitude of the lab, α is the orientation angle of \(\hat{y}\) with respect to the east direction in the horizontal plane. b The measured dots at different direction are fitted by a sinusoidal function. The error bars represent statistical errors (standard deviations).
