First study of single-neutron excitations of $^{\mathrm{207}}$Hg via the $^{\mathrm{206}}$Hg(d,p) reaction
ORAL
Abstract
We report the first exploration of the single-neutron shell structure of $^{\mathrm{207}}$Hg, which located below Z $=$ 82 and with N \textgreater 126 in an almost unexplored region of the nuclear chart. The $^{\mathrm{206}}$Hg(d,p) neutron-adding reaction in inverse kinematics at 7.4 MeV/u was performed at CERN's HIE-ISOLDE facility. The single-neutron excitations in $^{\mathrm{207}}$Hg were determined from the scattered protons, which were detected using the new ISOLDE Solenoidal Spectrometer at a magnetic field strength of 2.5 T. The Q-value resolution was 140 keV FWHM. Angular distributions suggest that the 0g$_{\mathrm{9/2}}$, 2d$_{\mathrm{5/2}}$, 3s$_{\mathrm{1/2}}$, 2d$_{\mathrm{3/2}}$ and 0g$_{\mathrm{7/2}}$ states were observed. An extrapolation of the single-particle energies using $^{\mathrm{209}}$Pb and $^{\mathrm{207}}$Hg as anchors towards the neutron threshold plays an important role in improving our understanding the r-process nucleosynthesis in this region.
*This work was supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under Contract Number DE-AC02-06CH11357 (ANL), the UK Science and Technology Facilities Council, the European Union's Horizon 2020 Framework research and innovation program under grant agreement no. 654002 (ENSAR2), the Research Foundation Flanders (FWO, Belgium), and the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013) / ERC grant agreement no. 617156.
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