Figure 1.
Background radiation vs GMA and CRA. Bck values (black) are increased compared to the first measurements outside the box. The indices seem to be not correlated. (a) There is no correlation between Bck and Dcx (red), although by visual inspection one can consider that there is a correlation. Most Dcx data oscillate close to 0 nT, and some other in the region between 10 nT and −50 nT; these data do not reflect any significant storm during the measuring period. (b) Neutron counts oscillate smoothly but close to 72 cps and are correlated with Bck.