First $\beta$-decay spectroscopy of ${}^{135}$In and new $\beta$-decay branches of ${}^{134}$In

Abstract

The $\beta$ decay of the neutron-rich ${}^{134}$In and ${}^{135}$In was investigated experimentally in order to provide new insights into the nuclear structure of the tin isotopes with magic proton number $Z=50$ above the $N=82$ shell. The $\beta$-delayed $\gamma$-ray spectroscopy measurement was performed at the ISOLDE facility at CERN, where indium isotopes were selectively laser-ionized and on-line mass separated. Three $\beta$-decay branches of ${}^{134}$In were established, two of which were observed for the first time. Population of neutron-unbound states decaying via $\gamma$ rays was identified in the two daughter nuclei of ${}^{134}$In, ${}^{134}$Sn and ${}^{133}$Sn, at excitation energies exceeding the neutron separation energy by 1 MeV. The $\beta$-delayed one- and two-neutron emission branching ratios of ${}^{134}$In were determined and compared with theoretical calculations. The $\beta$-delayed one-neutron decay was observed to be dominant $\beta$-decay branch of ${}^{134}$In even though the Gamow-Teller resonance is located substantially above the two-neutron separation energy of ${}^{134}$Sn. Transitions following the $\beta$ decay of ${}^{135}$In are reported for the first time, including $\gamma$ rays tentatively attributed to ${}^{135}$Sn. In total, six new levels were identified in ${}^{134}$Sn on the basis of the $\beta \gamma \gamma$ coincidences observed in the ${}^{134}$In and ${}^{135}$In $\beta$ decays. A transition that might be a candidate for deexciting the missing neutron single-particle $13/2^{+}$ state in ${}^{133}$Sn was observed in both $\beta$ decays and its assignment is discussed. Experimental level schemes of ${}^{134}$Sn and ${}^{135}$Sn are compared with shell-model predictions. Using the fast timing technique, half-lives of the $2^{+}$, $4^{+}$ and $6^{+}$ levels in ${}^{134}$Sn were determined.

References in corpus (21)

• Nuclear magic numbers: new features far from stability
• The impact of individual nuclear properties on $r$-process nucleosynthesis
• Evolution of shell structure in exotic nuclei
• Large scale evaluation of beta-decay rates of r-process nuclei with the inclusion of first-forbidden transitions
• The magic nature of 132Sn explored through the single-particle states of 133Sn
• Observation of new microsecond isomers among fission products of 345 MeV/nucleon 238U
• Neutron-gamma competition for $\beta$-delayed neutron emission
• Direct reaction measurements with a 132Sn radioactive ion beam
• Similarity of nuclear structure in 132Sn and 208Pb regions: proton-neutron multiplets
• Total Absorption Gamma-Ray Spectroscopy of 87Br, 88Br and 94Rb Beta-Delayed Neutron Emitters
• Effective interactions and shell model studies of heavy tin isotopes
• Isomerism in the "south-east" of ${}^{132}$Sn and a predicted neutron-decaying isomer in ${}^{129}$Pd
• Neutron-induced background by an alpha-beam incident on a deuterium gas target and its implications for the study of the 2H(alpha,gamma)6Li reaction at LUNA
• Structure of Sn isotopes beyond N=82
• Nuclear structure of 140Te with N = 88: Structural symmetry and asymmetry in Te isotopes with respect to the double-shell closure Z = 50 and N = 82
• Shell-model study of exotic Sn isotopes with a realistic effective interaction
• Detailed spectroscopy of doubly magic ${}^{132}$Sn
• ${\beta }^{-}$ decay study of the ${}^{66}$Mn - ${}^{66}$Fe - ${}^{66}$Co - ${}^{66}$Ni chain
• Neutron Interactions as Seen by A Segmented Germanium Detector
• First determination of $\beta$-delayed multiple neutron emission beyond A = 100 through direct neutron measurement: The P${}_{2n}$ value of ${}^{136}$Sb
• $\beta$ Decay of ${}^{132}$In and Spectroscopy of ${}^{132}$Sn and ${}^{131}$Sb with the GRIFFIN Spectrometer

Cited by in corpus (2)

• High-precision measurements of low-lying isomeric states in ${}^{120-124}$In with JYFLTRAP double Penning trap
• The 76Cu conundrum remains unsolved