Spectroscopy of neutron-richMn59−63isotopes

Low-energy structure ofMn61populated followingβdecay ofCrawford1, Mantica2, Berryman3 et al. 2009Phys. Rev. CSelf Cite19190View full textAdd to dashboardCite

“…[23] may be evidence for β-delayed neutron decay of the 62 Cr ground state. It is worth noting that the in-beam γ -ray spectra for 61 Mn and 62 Mn obtained by Valiente-Dobón et al [22] include transitions of energies 157 and 155 keV, respectively, supporting the present assignment of the 157-keV γ -ray transition in Fig. 4 to the decay of 61 Cr.…”

“…It is likely that the 1142-keV state has low spin, either J π = 1/2 − or J π = 3/2 − . The level at 1142 keV is apparently weakly fed by β decay, was not identified in the yrast structure of 61 Mn [22], and does not depopulate to the 7/2 − level at 157 keV within the statistical certainty of this measurement. The 1497-keV level is tentatively assigned a J π of 3/2 − or 5/2 − because of the apparent allowed β-decay branch and the favorable competition between the two depopulating γ rays that suggests both transitions have M1 multipolarity.…”

“…The first excited state at 157 keV has been tentatively assigned J π = 7/2 − from the in-beam γ -ray results [22]. Allowed β feeding to the lowest two states would then limit the J π quantum numbers of the 61 Cr ground state to values of 5/2 − or 7/2 − .…”

“…However, level structures are not available for Mn isotopes with N > 38. In-beam γ rays were recently measured for neutron-rich 59−63 Mn produced by multinucleon transfer between a 70 Zn projectile and 238 U target [22]. Only a single γ -ray transition was attributed to 63 Mn 38 .…”

Collective features of Cr and Fe isotopes

“…This latter model space is also good enough to account for the spectroscopy of moderately neutron-rich Mn [37] isotopes. However, when approaching N = 40 these fpg calculations fail to describe the structure of neutron-rich nuclei, in particular, [60][61][62] Cr [6,8,38] and 66 Fe [23].…”