Detailed spectroscopy of the neutron-unbound nucleus 28 F has been performed for the first time following proton/neutron removal from 29 Ne/ 29 F beams at energies around 230 MeV/nucleon. The invariant-mass spectra were reconstructed for both the 27 F ( * ) + n and 26 F ( * ) + 2n coincidences and revealed a series of well-defined resonances. A near-threshold state was observed in both reactions and is identified as the 28 F ground state, with Sn( 28 F) = −199(6) keV, while analysis of the 2n decay channel allowed a considerably improved Sn( 27 F) = 1620(60) keV to be deduced. Comparison with shell-model predictions and eikonal-model reaction calculations have allowed spin-parity assignments to be proposed for some of the lower-lying levels of 28 F. Importantly, in the case of the ground state, the reconstructed 27 F+n momentum distribution following neutron removal from 29 F indicates that PACS numbers:

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