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arXiv · 1512.00141

First Online Mass Measurements of Isobar Chains via Multi-Reflection Time-of-Flight Mass Spectrograph Coupled with GARIS-II

P. Schury·M. Wada·Y. Ito·D. Kaji·P-A Soderstrom·A Takamine·F Arai·H. Haba·S. Jeong·S. Kimura·H. Koura·H. Miyatake·K. Morimoto·K. Morita·A. Ozawa·M. Reponen·T. Sonoda·T. Tanaka·H. Wollnik
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Abstract

Using a mulit-reflection time-of-flight mass spectrograph (MRTOF-MS) located after a gas cell coupled with the gas-filled recoil ion separator GARIS-II, the masses of several heavy nuclei have been directly and precisely measured. The nuclei were produced via fusion-evaporation reactions and separated from projectile-like and target-like particles using GARIS-II before being stopped in a helium-filled gas cell. Time-of-flight spectra for three isobar chains, 205Fr-205Rn-205At-205Po, 206Fr-206Rn-206At and 201Rn-201At-201Po-201Bi, were observed. Precision atomic mass values were determined for 205,206Fr, 201At, and 201Po.

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P. Schury, M. Wada, Y. Ito, D. Kaji, P-A Soderstrom, A Takamine, F Arai, H. Haba, S. Jeong, S. Kimura, H. Koura, H. Miyatake, K. Morimoto, K. Morita, A. Ozawa, M. Reponen, T. Sonoda, T. Tanaka, H. Wollnik. 2015-12-01. First Online Mass Measurements of Isobar Chains via Multi-Reflection Time-of-Flight Mass Spectrograph Coupled with GARIS-II. https://doi.org/10.1103/physrevc.95.011305

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