ANOMALOUS 5/2+ AND 7/2+ STATES IN 99RH FROM DECAY OF 21 MIN 99PD

Levels in 99Rh populated in the decay of 21 min 99Pd were investigated. From singles γ-ray energy and intensity measurements employing high-resolution and efficiency Ge(Li) detectors, from coincidence relationships established from γ-γ coincidence experiments employing two Ge(Li) detectors and from β+-γ coincidence experiments employing a plastic scintillator and a Ge(Li) detector, it was found that levels at 64.6, 200.6, 427.3, 464.3, 851.1, 874.4, 1018.3, 1111.2, 1167.4, 1366.5, 1527.4, 1535.9, 1761.2, 1814.8, 1969.2, 2040.3, 2051.9, 2070.6, 2143.7, 2181.3, 2199.2, 2268.0, 2343.3, 2388.8, 2709.3, 2737.4, 2758.9 and 2835.4 keV are populated in the decay of 22 min 99Pd. Possible levels at 2618.1, 2639.4, 2860.3, 2957.4 and 3047.0 keV are suggested on the basis of energy sums. The fraction of decay of 99Pd to the 16 d 99Rh ground state was determined in milking experiments to be 0.02 ± 0.01 and from the proposed decay scheme, which gives 0.029 ± 0.002. From singles positon spectra and from β+-γ coincidence measurements, the QEC value for 99Pd decay was determined to be 3405 ± 20 keV. The half-life of 99Pd was measured to be 21.4 ± 0.2 min. From log ft values obtained and from γ-ray branching information, limits for the Jπ values of many levels in 99Rh were placed. The level structure of the anomalous" 5 2+ and 7 2+ states in 99Rh is compared with similar levels in other odd-mass Rh isotopes and with recent calculations on the pairing-plus-quadrupole model. © 1969."