[21a-P2-1~52] 1.2 Education

[21a-P2-45] The study of the half-life of ²¹⁴Pb by making use of natural hot spring water

〇Hiroto Ashikaga¹ (1.TUES)

Keywords:hot spring water,half-life,gamma ray spectrum

The hot spring water is a familiar radiation source. Of hot spring water, Misasa contains the most ²²²Rn, decaying to ²¹⁴Pb and ²¹⁴Bi. I attempted to observe the decay by means of beta rays using a Geiger counter, but it became necessary to separate ²¹⁴Pb and ²¹⁴Bi chemically. ²²²Rn was adsorbed to active carbon in this study and then heated after radioactive equilibrium. After heating, I measured the gamma ray spectrum of the remaining ²¹⁴Pb and ²¹⁴Bi using a 3-inch NaI high sensitivity scintillator every ten minutes. I was able to measure the half-life of ²¹⁴Pb using the strength ratio of the peaks as they damped.