Data No. Position [cm] Alpha count [%] 1 24.1 0.1 1050 3.9 2 26.7 0.1 1604 3.4 3 31.7 0.1 2379 3.1 4 41.8 0.1 4887 2.7 5 52.0 0.1 9848 2.5 6 62.1 0.1 17383 2.5 7 72.1 0.1 35977 2.3 8 77.2 0.1 65925 2.4