{"paper":{"title":"Microsecond Isomer at the N=20 Island of Shape Inversion Observed at FRIB","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"nucl-ex","authors_text":"A. A. Doetsch, A. Andalib, A. Chester, A. E. Stuchbery, A. Frotscher, A. Laminack, A. Nowicki, A. O. Macchiavelli, A. Poves, B. C. Rasco, B. Longfellow, B. P. Crider, B. R. Clark, C. Benetti, C. J. Prokop, C. M. Campbell, C. Morse, C. Porzio, D. Seweryniak, E. Argo, E. K. Ronning, E. Rubino, F. G. Kondev, H. Huegen, H. L. Crawford, I. Cox, J. A. Winger, J. Chan, J. Christie, J. D. Holt, J. Dopfer, J. G. Duarte, J. Heideman, J. L. Wood, J. M. Allmond, J. T. Harke, K. Kolos, K. P. Rykaczewski, K. Siegl, L. Schaedig, M. J. Mogannam, M. Madurga, M. P. Carpenter, M. Singh, N. Kitamura, P. Fallon, R. Grzywacz, R. Jain, R. Mahajan, R. S. Lubna, S. Bhattacharya, S. L. Tabor, S. Luitel, S. Neupane, S. N. Liddick, T. Gaballah, T. H. Ogunbeku, T. J. Gray, T. J. Ruland, T. L. Tang, T. Miyagi, T. T. King, T. Wheeler, V. Tripathi, W.-J. Ong, Z. Xu","submitted_at":"2023-02-22T19:12:51Z","abstract_excerpt":"Excited-state spectroscopy from the first Facility for Rare Isotope Beams (FRIB) experiment is reported. A 24(2)-$\\mu$s isomer was observed with the FRIB Decay Station initiator (FDSi) through a cascade of 224- and 401-keV $\\gamma$ rays in coincidence with $^{32}\\textrm{Na}$ nuclei. This is the only known microsecond isomer ($1{\\text{ }\\mu\\text{s}}\\leq T_{1/2} < 1\\text{ ms}$) in the region. This nucleus is at the heart of the $N=20$ island of shape inversion and is at the crossroads of spherical shell-model, deformed shell-model, and ab initio theories. It can be represented as the coupling of"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2302.11607","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2302.11607/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}