首次观测到无束缚核 15Ne。

First observation of the unbound nucleus 15Ne.

机构信息

Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany and GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany and ExtreMe Matter Institute EMMI and Research Division GSI, D-64291 Darmstadt, Germany and Frankfurt Institute for Advanced Studies FIAS, D-60438 Frankfurt am Main, Germany.

出版信息

Phys Rev Lett. 2014 Apr 4;112(13):132502. doi: 10.1103/PhysRevLett.112.132502.

DOI:10.1103/PhysRevLett.112.132502

PMID:24745409

Abstract

We report on the first observation of the unbound proton-rich nucleus 15Ne. Its ground state and first excited state were populated in two-neutron knockout reactions from a beam of 500 MeV/u 17Ne. The 15Ne ground state is found to be unbound by 2.522(66) MeV. The decay proceeds directly to 13O with simultaneous two-proton emission. No evidence for sequential decay via the energetically allowed 2- and 1- states in 14F is observed. The 15Ne ground state is shown to have a strong configuration with two protons in the (sd) shell around 13O with a 63(5)% (1s1/2)2 component.

摘要

我们报告了对未束缚的质子丰富核 15Ne 的首次观察。其基态和第一激发态是通过来自 500 MeV/u 17Ne 的束流的两次中子敲出反应产生的。15Ne 的基态被发现未束缚，结合能为 2.522(66) MeV。衰变直接进行到 13O，同时发射两个质子。没有观察到通过在 14F 中能量允许的 2-和 1-态进行顺序衰变的证据。15Ne 的基态被证明具有强烈的组态，其中两个质子在 13O 周围的 (sd) 壳层中，具有 63(5)%（1s1/2）2 分量。