Analogous negative parity spectra of125Xe and127Xe

The low spin states of the nucleus¹²⁷Xe have been investigated with the (, 2n) reaction by means of in-beam--spectroscopy, using theosiris-cube-spectrometer at the FNTandem accelerator facility of the University of Cologne. In the negative parity system, four excited states for each of the spins 11/2^–.15/2^– and two 5/2^–.9/2^– — states could be established at excitation energies up to 1MeV above the Yrast line. With this new data, we are able to compare the non-Yrast states and their decay properties to the corresponding states of¹²⁵Xe, which had been studied with similar methods in Cologne. The almost one-to-one correspondence between the states of these neighboring neutron-odd nuclei is a clear indication that their excitations at low spin remain collective well above the Yrast line.