First spatial separation of a heavy ion isomeric beam with a multiple-reflection time-of-flight mass spectrometer

摘要: Po-211 ions in the ground and isomeric states were produced via U-238 projectile fragmentation at 1000 MeV/u. The spatially separated flight from primary beam other reaction products by fragment separator FRS. energy-bunched, slowed-down thermalized a gas-filled cryogenic stopping cell (CSC). They then extracted CSC injected into high-resolution multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS). excitation energy of isomer and, for first time, isomeric-to-ground state ratio determined measured spectrum. In subsequent experimental step, isomers an ion deflector finally collected with silicon detector decay spectroscopy. This pioneering result opens up unique perspectives isomer-resolved studies. With this versatile method new half-lives longer than few milliseconds can be discovered their properties highest sensitivity selectivity. These experiments extended to studies beams nuclear reactions. (C) 2015 Authors. Published Elsevier B.V.