Isomeric yield ratios and mass spectrometry of Y and Nb isotopes in the neutron-rich N=60 region: the unusual case of $^{98}$Y
Fuente:
arXiv
Gespeichert in:
| Hauptverfasser: | , , , , , , , , , , , , , , , , |
|---|---|
| Format: | Preprint |
| Veröffentlicht: |
2025
|
| Schlagworte: | |
| Online-Zugang: | |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| _version_ | 1866908670064852992 |
|---|---|
| author | Cannarozzo, Simone Pomp, Stephan Kankainen, Anu Moore, Iain Stryjczyk, Marek Al-Adili, Ali Solders, Andreas Virtanen, Ville Eronen, Tommi Gao, Zhihao Ge, Zhuang Jaries, Arthur Lantz, Mattias Mougeot, Maxime Penttilä, Heikki Raggio, Andrea Ruotsalainen, Jouni |
| author_facet | Cannarozzo, Simone Pomp, Stephan Kankainen, Anu Moore, Iain Stryjczyk, Marek Al-Adili, Ali Solders, Andreas Virtanen, Ville Eronen, Tommi Gao, Zhihao Ge, Zhuang Jaries, Arthur Lantz, Mattias Mougeot, Maxime Penttilä, Heikki Raggio, Andrea Ruotsalainen, Jouni |
| contents | The isomeric yield ratio (IYR) of fission products is an observable that carries relevant information about the fragments emerging from the scission of a fissioning nucleus. We report on IYR of $^{96,98,100}$Y and $^{100,102}$Nb, together with the previously reported values for $^{97}$Y and $^{99}$Nb, produced in the 28 MeV $α$-induced fission of $^{232}$Th at the Ion Guide Isotope Separation On-Line (IGISOL) facility of the University of Jyv{ä}skyl{ä}. We measured the IYR using two different techniques, the phase-imaging ion-cyclotron-resonance (PI-ICR) and the multiple-reflection time-of-flight mass spectrometry (MR-TOF-MS) methods. Moreover, we measured the masses of the long-lived states in $^{98,100}$Y and $^{100,102}$Nb populated via in-trap $β$-decay of their precursors. Since the $β$-decay selectively populates states with a favourable spin-parity, we could identify the measured state and show that the ground state is the low-spin state in the cases of $^{98}$Y and $^{100}$Nb, while it is the high-spin state in the cases of $^{100}$Y and $^{102}$Nb. This measurement confirms the spin-parity assignments of all the nuclei as they are reported in the NUBASE2020 evaluations, disagreeing with the assignment for $^{100}$Y reported in the ENSDF evaluation.
Making also use of previously reported data, we observe an anomalously low IYR for the $N=59$ isotope $^{98}$Y as compared to other yttrium or neighboring niobium isotopes. This behavior is very rare across the nuclear chart and is posited to be connected to the characteristic shape coexistence of $^{98}$Y, and to the change in the charge radii of the ground and excited states in the $N=58-60$ region. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2504_11274 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Isomeric yield ratios and mass spectrometry of Y and Nb isotopes in the neutron-rich N=60 region: the unusual case of $^{98}$Y Cannarozzo, Simone Pomp, Stephan Kankainen, Anu Moore, Iain Stryjczyk, Marek Al-Adili, Ali Solders, Andreas Virtanen, Ville Eronen, Tommi Gao, Zhihao Ge, Zhuang Jaries, Arthur Lantz, Mattias Mougeot, Maxime Penttilä, Heikki Raggio, Andrea Ruotsalainen, Jouni Nuclear Experiment The isomeric yield ratio (IYR) of fission products is an observable that carries relevant information about the fragments emerging from the scission of a fissioning nucleus. We report on IYR of $^{96,98,100}$Y and $^{100,102}$Nb, together with the previously reported values for $^{97}$Y and $^{99}$Nb, produced in the 28 MeV $α$-induced fission of $^{232}$Th at the Ion Guide Isotope Separation On-Line (IGISOL) facility of the University of Jyv{ä}skyl{ä}. We measured the IYR using two different techniques, the phase-imaging ion-cyclotron-resonance (PI-ICR) and the multiple-reflection time-of-flight mass spectrometry (MR-TOF-MS) methods. Moreover, we measured the masses of the long-lived states in $^{98,100}$Y and $^{100,102}$Nb populated via in-trap $β$-decay of their precursors. Since the $β$-decay selectively populates states with a favourable spin-parity, we could identify the measured state and show that the ground state is the low-spin state in the cases of $^{98}$Y and $^{100}$Nb, while it is the high-spin state in the cases of $^{100}$Y and $^{102}$Nb. This measurement confirms the spin-parity assignments of all the nuclei as they are reported in the NUBASE2020 evaluations, disagreeing with the assignment for $^{100}$Y reported in the ENSDF evaluation. Making also use of previously reported data, we observe an anomalously low IYR for the $N=59$ isotope $^{98}$Y as compared to other yttrium or neighboring niobium isotopes. This behavior is very rare across the nuclear chart and is posited to be connected to the characteristic shape coexistence of $^{98}$Y, and to the change in the charge radii of the ground and excited states in the $N=58-60$ region. |
| title | Isomeric yield ratios and mass spectrometry of Y and Nb isotopes in the neutron-rich N=60 region: the unusual case of $^{98}$Y |
| topic | Nuclear Experiment |
| url | https://arxiv.org/abs/2504.11274 |