通过β延迟带电粒子光谱法首次观测到\(^{13}O\)的β3αp衰变

First Observation of the β3αp Decay of ^{13}O via β-Delayed Charged-Particle Spectroscopy.

作者信息

Bishop J, Rogachev G V, Ahn S, Barbui M, Cha S M, Harris E, Hunt C, Kim C H, Kim D, Kim S H, Koshchiy E, Luo Z, Park C, Parker C E, Pollacco E C, Roeder B T, Roosa M, Saastamoinen A, Scriven D P

机构信息

Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA.

Department of Physics and Astronomy, Texas A&M University, College Station, Texas 77843, USA.

出版信息

Phys Rev Lett. 2023 Jun 2;130(22):222501. doi: 10.1103/PhysRevLett.130.222501.

DOI:10.1103/PhysRevLett.130.222501

PMID:37327448

Abstract

The β-delayed proton decay of ^{13}O has previously been studied, but the direct observation of β-delayed 3αp decay has not been reported. Rare 3αp events from the decay of excited states in ^{13}N^{⋆} provide a sensitive probe of cluster configurations in ^{13}N. To measure the low-energy products following β-delayed 3αp decay, the Texas Active Target (TexAT) time projection chamber was employed using the one-at-a-time β-delayed charged-particle spectroscopy technique at the Cyclotron Institute, Texas A&M University. A total of 1.9×10^{5} ^{13}O implantations were made inside the TexAT time projection chamber. A total of 149 3αp events were observed, yielding a β-delayed 3αp branching ratio of 0.078(6)%. Four previously unknown α-decaying excited states were observed in ^{13}N at 11.3, 12.4, 13.1, and 13.7 MeV decaying via the 3α+p channel.

摘要

此前已对(^{13}O)的β延迟质子衰变进行了研究，但尚未报道对β延迟(3αp)衰变的直接观测。来自(^{13}N^{\star})激发态衰变的罕见(3αp)事件为(^{13}N)中的团簇构型提供了一个灵敏的探针。为了测量β延迟(3αp)衰变后的低能产物，在德克萨斯农工大学回旋加速器研究所使用一次一个的β延迟带电粒子光谱技术，采用了德克萨斯有源靶（TexAT）时间投影室。在TexAT时间投影室内总共进行了(1.9×10^{5})次(^{13}O)注入。总共观测到149个(3αp)事件，得到的β延迟(3αp)分支比为(0.078(6)%)。在(^{13}N)中观测到四个先前未知的α衰变激发态，能量分别为11.3、12.4、13.1和13.7 MeV，通过(3α + p)通道衰变。