Image
Fig. 1 (left). The asymmetry in the 501 keV transition of 180mHf at different temperatures. The final field reversal gives a null effect as expected since at 1 K the source is unpolarized. The scatter of the individual points reflects the statistics of each point.
Fig. 2 (right). The dilution refrigerator NICOLE in the ISOLDE hall, with the beam line (to the left), cryostat and Ge detectors visible.