Search For C-21 And Constraints On C-22
A search for the neutron-unbound nucleus 21C was performed via the single-proton removal reaction from a beam of 22N at 68 MeV/u. Neutrons were detected with the Modular Neutron Array (MoNA) in coincidence with 20C fragments. No evidence for a low-lying state was found, and the reconstructed decay-energy spectrum could be described with an s-wave line shape with a scattering length limit of |as|22C is bound by less than 70 keV.
Mosby, S., N. S. Badger, T. Baumann, D. Bazin, M. Bennett, J. Brown, G. Christian, Paul A. DeYoung, J. E. Finck, M. Gardner, J. D. Hinnefeld, E. A. Hook, E. M. Lunderberg, B. Luther, D. A. Meyer, M. Mosby, Graham F. Peaslee, W. F. Rogers, J. K. Smith, J. Snyder, A. Spyrou, M. J. Strongman and M. Thoennessen. "Search for C-21 and Constraints on C-22." Nuclear Physics A 909 (2013). http://dx.doi.org/10.1016/j.nuclphysa.2013.04.004