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Absolute K-shell x-ray production cross sections for thin Ca, Sc, Ti, V, Fe, Ni, Cu, Zn, Ge, Rb, Sr, Y, Zr, and Pd targets have been measured for incident carbon ions in the energy range from 8 to 36 MeV. Ionization cross sections are calculated from atomic K-shell Quorescence yields and compared to the theoretical predictions of the plane-wave Born approximation including binding energy, Coulomb deflection, and relativistic corrections. K&/KP ratios and the shifts in the characteristic Ku and KP energies indicate the existence of multiple ionization in the low-Z targets.

We have measured projectile and target x-ray cross sections for F+ Ar and F+ Kr collisions using fluorine beams of charge states 7+, 8+, and 9+ with energies from 20 to 76 MeV. Pronounced enhancements for the Ar K and Kr L vacancy cross sections using F + ions compared to those for the 7+ projectile can be explained by charge exchange as described by an empirically scaled Brinkman-Kramers theory. The Ar L, Kr K, and Kr M cross sections are found to exhibit features expected for Coulomb ionization. The projectile K xray production for the 9+ ion is accounted for by charge exchange processes. Predictions of the first Born approximation for direct single-step excitation to bound states by the target nucleus overestimate the observed cross sections for F'+ and F'+.

The electron-capture decay of BaIJ3 and the subsequent de-excitation of Cs133 have been investigated with magnetic and scintillation spectrometers. The measured conversion coefficients and transition intensities lead to the following spin assignments for the states of ground, 7/2+; 81 kev, 5/2+; 161 kev, 5/2+; 383 kev, 3/2+; and 437 kev, 1/2+. The multipolarities of the connecting transitions are: 54 kev ( M I ) , 80 kev ( M l ) , 81 kev ( M l ) , 161 kev ( M l + E 2 ) , 276 kev (E2), 302 kev ( M l + E 2 ) , 356 kev (E2), and 383 kev (E2). The limits of experimental error in the measured conversion coefficients do not exclude the possibility that the 437-kev level is 3/2+ and that both the 276-and 356-kev transitions are Ml+E2 admixtures.

Absolute L-shell x-ray production cross sections have been measured for thin targets of Pd, Ag, and Sn at 1-MeV increments for incident protons in the range from 3 to 12 MeV and in 5-MeV increments for oxygen ions in the range from 15 to 40 MeV. L-shell ionization cross sections are calculated from theoretical average L-shell fluorescence yields and then compared to both plane-wave Born-approximation (PWBA) and binary-encounter-approximation (BEA) theories. The data are found to be higher than the theoretical predictions except at the lowest projectile energies.