NUSPIN 2017

By combining the mass resolving power of SHIPTRAP with the charged-particle- multicoincidence setup TASISpec [1] the decay path of the 213Ra ground state has been exclusively studied and revised decay data has been obtained. In regions far from the line of beta-stability the preparation of isotopically clean sources and thus unambiguous decay information becomes most essential and challenging. With the aid of virtual experiments using Geant4 [2, 3], high-resolution quantum-state selective decay spectroscopy enables insight in these regions. The experimental scheme has been realized at GSI Darmstadt where a 48Ca beam, provided by the UNIversal Linear ACcelerator (UNILAC), was impinging on a thin 170Er target foil. After standard velocity filtering in the Separator for Heavy Ion reaction Products (SHIP), the nuclear ground state of 213Ra was mass-selected in SHIPTRAP [4] and transferred to the TASISpec decay-station. The most resent as well as most comprehensive study of 213Ra has been has been performed by Kuusiniemi et al. [5]. However, the beat-+/EC-branching of the 213Ra ground state has been unchanged since the first studies nearly 50 years ago [6]. This study exemplifies the immense potential of high-resolution quantum-state selective decay spectroscopy to gain insight into nuclear structure properties. [1] L.-L. Andersson et al., Nucl. Instrum. Meth. A 622, 164 (2010). [2] L.G. Sarmiento, L.-L. Andersson, D. Rudolph, Nucl. Instrum. Meth. A 667, 26 (2012). [3] L.G. Sarmiento, D. Rudolph, AIP conference series (in press) [4] M. Block et al., Eur. Phys. J. D 45, 39 (2007). [5] P. Kuusiniemi et al., Eur. Phys. J. A 30, 551 (2006). [6] K. Valli, W. Treytl, and Earl K. Hyde, Phys. Rev. 161, 1284 (1967). This work is supported in part by the Swedish Research Council (VR 2011-5253 and VR 2013-4271), the Knut and Alice Wallenberg Foundation (KAW 2015.0021),