Fig. 9
From: Scanning SQUID microscope system for geological samples: system integration and initial evaluation
Background noise of SQUID magnetometer measured on a July 7, 2015, and b July 9, 2015, for 1 h. In both recordings, a long-term drift component (>1 nT in a) is seen together with the periodic fluctuations of about 60–90 s. c, d Expanded 30-s measurement from a and b, respectively. e Background noise of the SQUID sensor itself measured in a superconducting magnetic shield for 30 s at a sampling rate of 100 Hz with an LPF of 10 Hz