Spectroscopy and high-spin structure of Fr209

Excited states in Fr-209 have been studied using the Au-197(O-16,4n)Fr-209 reaction with pulsed beams and gamma-ray and electron spectroscopy. A comprehensive scheme has been established up to an excitation energy of about 6 MeV and spins of about 49/2h. Several isomers have been identified including a J(pi)=25/2(+), tau=48(3) ns state at 2130 keV and a 606(26) ns, 45/2(-) state at 4660 keV. The latter state decays via an enhanced E3 transition with a strength of 28.8(12) W.u. It can be identified with a similar isomer in the heavier odd isotopes Fr-211 and Fr-213, arising from the maximal coupling of the five valence protons in the pi h(9/2)(3)i(13/2)(2) configuration. The systematics of the yrast states in the odd-A isotopes are discussed, including the presence of states arising from the main proton configurations coupled to the p(1/2), f(5/2), and i(13/2) neutron holes. Shell-model configurations are assigned to many of the observed states. The isotopic assignment differs from earlier work, which is shown to be erroneous.