“No-spin” states and low-lying structures in130Xe and136Xe

T.J Ross,A Chakraborty,E.E Peters,M.T Mcellistrem,J.R Vanhoy,F.M Prados-Estévez,B.P Crider,S.W Yates,S.H Liu,A Kumar

doi:10.1051/epjconf/20159301010

T.J Ross, A Chakraborty + Show 8 more

Open Access

https://doi.org/10.1051/epjconf/20159301010

Copy DOI

Abstract

Inelastic neutron scattering on solid 130 XeF 2 and 136 XeF 2 targets was utilized to populate excited levels in 130 Xe and 136 Xe. When calculating nuclear matrix elements vital to the understanding of double-beta decay, it is important to have a clear understanding of the low-lying level structure of both the parent and daughter nucleus. Of particular relevance to double-beta decay searches are the assignments of 0 + states. We show here that in the case of 130 Xe there are several discrepancies in the adopted level structure. We found that one previous 0 + candidate level (1590 keV) can be ruled out and assigned two additional candidates (2223 and 2242 keV). In 136 Xe we question the previous assignment of a 0 + level at 2582 keV. Excitation function and angular distribution measurements were utilized to make spin and parity assignments of levels and place new transitions.

Highlights

Aside from tin, xenon has the longest chain of stable isotopes on the nuclear chart, and yet the low-energy structure remains relatively unstudied due to xenon’s gaseous nature
If the ultra-rare process is discovered, it would confirm the neutrino as its own anti particle and the neutrino mass could be extracted. 136Xe is of interest because it is a candidate “parent” nucleus for the process, decaying to 136Ba
If one is to extract a neutrino mass, following a direct observation of the process, it is important that one understands the nuclear structure of the isotopes involved, as they play a major role in the calculation of nuclear matrix elements, [7]

Summary

Introduction

Aside from tin, xenon has the longest chain of stable isotopes on the nuclear chart, and yet the low-energy structure remains relatively unstudied due to xenon’s gaseous nature. Xenon isotopes are of timely interest for neutrinoless double-beta decay applications. If the ultra-rare process is discovered, it would confirm the neutrino as its own anti particle and the neutrino mass could be extracted. If one is to extract a neutrino mass, following a direct observation of the process, it is important that one understands the nuclear structure of the isotopes involved, as they play a major role in the calculation of nuclear matrix elements, [7]. Such states are important both from the point-of-view of understanding the nuclear structure in this region and for nuclear matrix element calculations

Experiment

Results

States in 130Xe

Conclusion