Y. H. Zhang, Institute of Modern Physics, Chinese Academy of Sciences
Precision mass measurements of short-lived nuclides at storage ring in Lanzhou
Argonne Physics Division Seminar - 2015
3:30 PM, Building 203, Conference Room R-150

Nuclear mass is the fundamental property of a nucleus. The complex interplay of strong, weak and electromagnetic interactions in the nucleus contributes to the difference between its mass and the sum of the masses of its constituent nucleons. Precise and systematic measurements of nuclear masses not only provide information on nuclear structure, but also find their important applications in nuclear astrophysics. Recent commissioning of the Cooler Storage Ring at the Heavy Ion Research Facility in Lanzhou (HIRFL-CSR) has allowed us for direct mass measurements at the Institute of Modern Physics in Lanzhou (IMP), Chinese Academy of Sciences (CAS). In the past few years, a series of mass measurement experiments have been carried out using the CSRe-based isochronous mass spectrometry (IMS). Masses of short-lived nuclides of both neutron-rich and neutron-deficient have been measured up to a relative precision of 10-6 to 10-7 via fragmentation of the energetic beams of 58Ni, 78Kr, 86Kr, and 112Sn [1, 2, 3, 4, 5]. In this seminar, the experiments and the results will be presented. The implications of our experimental results with respect to nuclear structures and stellar nucleosynthesis in the rp-process of x-ray bursts are discussed. Some disadvantages in the IMS method itself are pointed out and simulated, and further improvement using double ToF detectors are proposed.

[1] X. L. Tu et al, Phys. Rev. Lett. 106, 112501 (2011)
[2] X. L. Tu et al., Nucl. Instrum. Meth. A 654 ,213 (2011)
[3] Y. H. Zhang et al, Phys. Rev. Lett. 109, 102501 (2012)
[4] X. L. Yan et al., AstroPhys. Jour. Lett. 766, L8 (2013)
[5] P. Shuai et al., Phys. Lett. B 735, 327 (2014)

Argonne Physics Division Seminar Schedule