Mass measurements of exotic nuclides at SHIPTRAP

The Penning trap mass spectrometer SHIPTRAP is installed behind the velocity‐filter SHIP at GSI for high‐precision mass measurements of fusion‐evaporation residues. To facilitate an efficient stopping of the reaction products a buffer gas stopping cell is utilized. In an investigation of neutron‐deficient nuclides in the terbium‐to‐thulium region around A ≈ 146, 18 new or improved mass values have been obtained, resulting in a more accurate determination of the proton drip line for holmium and thulium. With the present performance of SHIPTRAP, a first direct mass measurement of transuranium elements in the nobelium region is within reach.