Nuclear Data Sheets for A=73

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Experimental nuclear structure data for the known A=73 isobaric nuclides (Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Kr, Rb and Sr) have been evaluated, and presented together with Adopted properties of level energies, and associated γ rays. The decay data for these nuclides have also been evaluated, providing Adopted values of γ and β radiations, and log ft values. For 73Mn, only the isotopic identification has been established, with no knowledge of its g.s. half-life. For 73Fe, 73Co and 73Sr, only the ground states and their half-lives are known with no information about the excited states. For 73Ni, 73Cu, 73Zn and 73Rb, little data are available for excited states. The half-life and decay modes of possibly proton-unbound 73Rb need firmly established. 73Ga structure presents a special challenge in that the 1/2− ground state and the first 3/2− state have recently been proposed, in a Coulomb excitation experiment by 2010Di14, to form an almost degenerate doublet with an estimated spacing of <0.3 keV, which is a third example in the entire nuclear chart where first excited nuclear state can lie lower than 1 keV, the other being 229Th with its first excited state at 7.8 eV, and 235U with its first excited state at 76 eV. Ultra-high resolution gamma-ray spectroscopic studies are warranted to search for the low-lying (<0.3 keV) first excited state in 73Ga, and to determine its half-life. Level structures of 73Ga, 73Ge, 73As, 73Se, 73Br and 73Kr are quite well known, although decay schemes of radioactive ground states of 73Co, 73Cu and 73Br are considered incomplete.The reactions and decays for which no new experimental information has become available since the 2003 update have undergone revisions to incorporate conversion coefficients from BrIcc code, and evaluated Q values from 2017Wa10, but essential content of such datasets may have remained the same as in previous evaluations. In this respect the present work greatly benefited from all the previous NDS evaluations (2004Si08,1993Ki25,1987Ki13, 1980Ek01,1974Al33), but at the same time data presented herein supersede all the previous published evaluations.