强扁椭球形变\(^{149}Lu\)的纳秒级质子发射

Nanosecond-Scale Proton Emission from Strongly Oblate-Deformed ^{149}Lu.

作者信息

Auranen K, Briscoe A D, Ferreira L S, Grahn T, Greenlees P T, Herzáň A, Illana A, Joss D T, Joukainen H, Julin R, Jutila H, Leino M, Louko J, Luoma M, Maglione E, Ojala J, Page R D, Pakarinen J, Rahkila P, Romero J, Ruotsalainen P, Sandzelius M, Sarén J, Tolosa-Delgado A, Uusitalo J, Zimba G

机构信息

Accelerator Laboratory, Department of Physics, University of Jyväskylä, FI-40014 Jyväskylä, Finland.

Centro de Física e Engenharia de Materiais Avançados CeFEMA, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais, P1049-001 Lisbon, Portugal.

出版信息

Phys Rev Lett. 2022 Mar 18;128(11):112501. doi: 10.1103/PhysRevLett.128.112501.

DOI:10.1103/PhysRevLett.128.112501

PMID:35363028

Abstract

Using the fusion-evaporation reaction ^{96}Ru(^{58}Ni,p4n)^{149}Lu and the MARA vacuum-mode recoil separator, a new proton-emitting isotope ^{149}Lu has been identified. The measured decay Q value of 1920(20) keV is the highest measured for a ground-state proton decay, and it naturally leads to the shortest directly measured half-life of 450_{-100}^{+170} ns for a ground-state proton emitter. The decay rate is consistent with l_{p}=5 emission, suggesting a dominant πh_{11/2} component for the wave function of the proton-emitting state. Through nonadiabatic quasiparticle calculations it was concluded that ^{149}Lu is the most oblate deformed proton emitter observed to date.

摘要

利用熔合蒸发反应(^{96}Ru(^{58}Ni,p4n)^{149}Lu)和MARA真空模式反冲分离器，已鉴定出一种新的发射质子的同位素(^{149}Lu)。测得的衰变Q值为1920(20) keV，是基态质子衰变所测得的最高值，这自然导致基态质子发射体的直接测量最短半衰期为(450_{-100}^{+170}) ns。衰变率与(l_p = 5)发射一致，表明发射质子态的波函数具有主导的(\pi h_{11/2})成分。通过非绝热准粒子计算得出结论，(^{149}Lu)是迄今为止观测到的最扁长变形的质子发射体。