对$^{180m}$Ta衰变的约束
核实验
2024-08-02 v1 高能物理 - 实验
摘要
Ta是一种罕见的核同质异能态，其衰变从未被观测到。由于同质异能态与低能态之间较大的K自旋差和较小的能量差，其极长的寿命超过了所有其他已知的和电子俘获衰变的半衰期。探测其衰变是一项重大实验挑战，但有助于阐明中微子诱导的核合成机制、暗物质本质以及K自旋破坏。在本研究中，我们重新利用了MAJORANA DEMONSTRATOR——一个使用高纯锗探测器阵列搜寻Ge无中微子双β衰变的实验，以搜寻Ta的衰变。在超低本底探测器阵列中安装了超过17公斤钽金属，这是此类搜寻中使用过的最大钽金属量。本文给出了首年Ta数据采集的结果，并提供了不同衰变通道上Ta半衰期的最新限值。新限值高达1.5 x 年，我们将现有限值提高了1至2个数量级。该结果是迄今对单一和电子俘获衰变最灵敏的搜寻。
引用
@article{arxiv.2306.01965,
title = {Constraints on the decay of $^{180m}$Ta},
author = {I. J. Arnquist and F. T. Avignone and A. S. Barabash and C. J. Barton and K. H. Bhimani and E. Blalock and B. Bos and M. Busch and M. Buuck and T. S. Caldwell and C. D. Christofferson and P. -H. Chu and M. L. Clark and C. Cuesta and J. A. Detwiler and Yu. Efremenko and H. Ejiri and S. R. Elliott and G. K. Giovanetti and J. Goett and M. P. Green and J. Gruszko and I. S. Guinn and V. E. Guiseppe and C. R. Haufe and R. Henning and D. Hervas Aguilar and E. W. Hoppe and A. Hostiuc and I. Kim and R. T. Kouzes and T. E. Lannen and A. Li and J. M. Lopez-Castano and R. Massarczyk and S. J. Meijer and W. Meijer and T. K. Oli and L. S. Paudel and W. Pettus and A. W. P. Poon and D. C. Radford and A. L. Reine and K. Rielage and A. Rouyer and N. W. Ruof and D. C. Schaper and S. J. Schleich and T. A. Smith-Gandy and D. Tedeschi and R. L. Varner and S. Vasilyev and S. L. Watkins and J. F. Wilkerson and C. Wiseman and W. Xu and C. -H. Yu and D. S. M. Alves and H. Ramani},
journal= {arXiv preprint arXiv:2306.01965},
year = {2024}
}