High-precision mass measurements of neutron-deficient indium isotopes with ISOLTRAP: radioactive atoms were produced by nuclear reactions of 1.4 GeV protons impinging on a thick lanthanum carbide target; short-lived indium atoms diffusing from the target were selectively ionized using a two-step laser excitation scheme, provided by the ISOLDE RILIS, which excited one electron above the indium ionization potential (IP); the extracted ion beam was mass separated and injected into a radiofrequency quadrupole (RFQ) ion trap sitting on a high-voltage (HV) platform, where it was bunched and cooled; the beam was then processed by an MR-ToF MS to separate the indium ions from the isobaric contaminants; when the precision Penning trap was used for the mass measurement, further cooling and purification of the beam was achieved using a helium buffer-gas-filled preparation Penning trap; a position-sensitive microchannel plate (MCP) detector was used to record the time of flight and/or the position of the ion after ejection from the precision Penning trap; in the case of indium-99, for which the production yield was too low, the MR-ToF MS was used to perform the mass measurement. Image credit: Mougeot et al., doi: 10.1038/s41567-021-01326-9.