Atomic masses of intermediate-mass neutron-deficient nuclei with relative uncertainty down to 35-ppb via MRTOF-MS

ORAL

Abstract

Intermediate mass nuclei along the N = Z line are important components of the rp-process and accurate high-precision masses are crucial data. Half-lives of the key nuclei in the rp-process are of the order of several ten milliseconds to several seconds. The multireflection time-of-flight mass spectrograph (MRTOF-MS) has an advantage in achieving precision mass measurements for short-lived nuclei, owing to its measurement time being less than 10 ms. The SHE-mass facility, consists of the gas-filled recoil ion separator GARIS-II and an MRTOF-MS, has been developed to enable mass measurements of superheavy elements produced at RIKEN. It is also applicable to mass measurements of rp-process nuclei. Precision mass measurements of 63Cu, 64-66Zn, 65Ga, 65-67Ge, 67As, 78,81Br, 80Rb, and 79Sr were performed with the SHE-mass facility. In this experiment, for 65Ga, a relative precision of δm/m = 3.5x10-8 was obtained and the mass value was in excellent agreement with the 2016 Atomic Mass Evaluation.

We will report initial efforts using the SHE-mass facility for masses of rp-process nuclei, and will discuss future plans.

*Japan Society for the Promotion of Science, Grant No. 24224008, 15H02096, 15K05116, and 17H06090. US National Science Foundation, PHY1565546 and PHY1430152.

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Presenters

  • Sota Kimura

    • RIKEN

Authors

  • Sota Kimura

    • RIKEN

  • Yuta Ito

    • Japan Atomic Energy Agency
    • JAEA

  • Daiya Kaji

    • RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
    • RIKEN

  • Peter Schury

    • Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
    • KEK

  • Michiharu Wada

    • Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
    • KEK

  • Hiromitsu Haba

    • RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
    • RIKEN

  • Takashi Hashimoto

    • IBS

  • Yoshikazu Hirayama

    • Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
    • KEK

  • Marion MacCormick

    • IPN Orsay

  • Hiroari Miyatake

    • Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
    • KEK

  • Jun-young Moon

    • IBS

  • Kouji Morimoto

    • RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
    • RIKEN

  • Momo Mukai

    • University of Tsukuba

  • Ian Murray

    • IPN Orsay

  • A. Ozawa

    • University of Tsukuba

  • Marco Rosenbusch

    • RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
    • RIKEN

  • Hendrik Schatz

    • Michigan State University
    • National Superconducting Cyclotron Laboratory
    • Michigan State Univ

  • Aiko Takamine

    • RIKEN Nishina Center
    • RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
    • RIKEN

  • Taiki Tanaka

    • RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
    • RIKEN

  • Yutaka Watanabe

    • Wako Nuclear Science Center (WNSC), Institute of Particle and Nuclear Studies (IPNS), High Energy Accelerator Research Organization (KEK), Wako, Saitama 351-0198, Japan
    • KEK

  • Hermann Wollnik

    • New Mexico State University, Las Cruces, NM 88001, USA
    • New Mexico State University