Revalidation of the isobaric multiplet mass equation at A=53, T=3/2

The T = 3/2 isobaric analog state (IAS) in Co-53 is firmly established through a comprehensive measurement of beta-delayed gamma and proton decay of Ni-53. The determined excitation energy of Co-53 IAS combined with the mass of Co-53 generates a precise mass excess of -38 333.6(27) keV for the Co-53 IAS, which is 70(18) keV lower than the previously adopted value. The new result solves a problem raised by incorrect assignments of the Co-53 IAS of unexpected deviation from the isobaric multiplet mass equation (IMME) at A = 53, T = 3/2. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license.