Study on double beta-decays of <^(128)Te> and <^(130)Te> .

<^(128)Te>和<^(130)Te>双β衰变研究。

• 批准号: 60460012
• 负责人: TAKAOKA Nobuo
• 金额: $ 4.8万
• 依托单位: Yamagata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1986
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-60460012/
• 关键词: Double beta-decay; Half-life

1) From a tellurium mineral collected at the Suwa mine, Japan, a half-life for double beta-decay of <^(130)Te> has been determined to be (8.5 <+!-> 1.2) x <10^(20)> years. This result is in good agreement with the half-life reported by Takaoka and Ogata (1966) and that given by the Missouri group (Manuel, 1986), and different from the half-life given by the Heidelberg group (Kirsten et al., 1986).2) For a tellurium mineral (petzite, <Ag_3> AuTe) collected at the Cash mine, Co. USA, we have determined the amount of <^(130)Xe> produced by double beta-decay of <^(130)Te> . The half-life is (8.6 <+!-> 2.3) x <10^(20)> years with assumptions of a mineral age of Laramide (63 <+!-> 17 Ma) and of a tellurium content of 20% that was estimated from the chemical formula of petzite.3) K-Ar dating gives extra-ordinarily old ages for tellurium-bearing calcitequartz veins collected at the Suwa and Oya mines, Japan. The apparent ages are three to eight times older than the ages which have been considered to be correct from geological and geochronological evidence. This indicates that minerals in these veins contain excess Ar, and hence that the K-Ar dating of low potassium minerals such as calcite and tellurium minerals may give incorrect, possibly older ages for the formation of tellurium ores.

1)从日本Suwa矿采集的碲矿物中，测得<^（130）Te>的双β衰变半衰期为（8.5+！->1.2)x <10^（20）>年。该结果与Takaoka和Ogata（1966）报告的半衰期以及密苏里州小组（Manuel，1986）给出的半衰期非常一致，但与Heidelberg小组（Kirsten等人，1986年）。2）对于在美国Cash矿山公司采集的碲矿物（钙钛矿，<Ag_3>AuTe），我们已经确定了由&lt;^（130）Te&gt;的双β衰变产生的&lt;^（130）Te&gt;的量。半衰期为（8.6 &lt;+！-&gt; 2.3)x &lt;10^（20）&gt;年，假设矿物年龄为Laramide（63 &lt;+！-&gt; 3）K-Ar年龄测定给出了日本Suwa和Oya矿区含碲方解石石英脉的异常年龄。表观年龄比地质学和年代学证据中被认为是正确的年龄大三到八倍。这表明这些矿脉中的矿物含有过量的Ar，因此，低钾矿物如方解石和碲矿物的K-Ar定年可能给出不正确的，可能更老的碲矿石形成年龄。